| Home |
| Search |
| Today's Posts |
 |
|
Menu
| Woodworking (rec.woodworking) Discussion forum covering all aspects of working with wood. All levels of expertise are encouraged to particiapte. |
| Reply |
|
|
LinkBack | Thread Tools | Display Modes |
|
|
| Woodworking (rec.woodworking) Discussion forum covering all aspects of working with wood. All levels of expertise are encouraged to particiapte. |
| Reply |
|
|
LinkBack | Thread Tools | Display Modes |
|
#41
|
|||
|
|||
Salt and vinegar for rust removal
On Sun, 16 May 2004 18:56:02 -0500, Unknown
posted: On Fri, 14 May 2004 16:30:02 GMT, "Dan White" wrote: ,; ,;"Charles Erskine" wrote in message le.com... ,; More than you probably wanted to know: ,; ,; http://yarchive.net/metal/rust_remove.html ,; ,; snip ,; ,;This is the post I pasted in this thread originally to try and answer the ,;original question. OK I missed your original post. I wrote the article you refer to. I am a chemist and do know what is happening in this procedure so let's start fresh. What is it that needs more clarification on this topic? You ask the questions and I will try to give a reasonable explanation. Why do you need salt in the acetic acid to increase the rust removal? |
|
#42
|
|||
|
|||
|
Salt and vinegar for rust removal
On Thu, 13 May 2004 22:15:37 -0500, Unknown
posted: On Thu, 13 May 2004 09:04:26 -0700, Larry Blanchard wrote: ,;In article , says... ,; Ditto! All I can say is that the presence of ions in solution, ionic ,; strength, does definitely affect how species in solution react. Maybe there ,; is some physical chemistry website or ng you can visit and ask this ,; question. I'd be interested to know, too! ,; ,;Wow! I didn't mean to start such a learned discussion :-). My ,;knowledge of chemistry is limited to making various explosive ,;compounds, learned long ago in my juvenile days. And lately, I ,;think I've forgotten most of that - CRS seting in :-). ,; ,;But what I meant by "ask a chemist" is that a friend of mine who ,;is a chemist said that the vinegar and salt combined to form a ,;weak hydrochloric acid. I took his word for it. You shouldn't have as he was wrong. Vinegar is approximately 5% acetic acid plus some other goodies to provide some taste. The hydrogen ion concentration is not sufficient to react with metallic iron and therein lies one of the keys to the process. The other key is the fact that chloride ions form a stable complex with iron ions in solution. The iron chloride complex is strong enough so that iron oxide will dissolve and form that complex. Since there is no oxidant strong enough to react with iron metal the net result is that the iron oxide goes into solution as the chloride but the iron metal does not react. It is essential that the solution be kept oxygen free or the metal will dissolve. This is particularly noticeable if you allow the metal to be "derusted" to stick out of the solution into air e.g. you will find that there has been a dissolution of iron metal at the air liquid interface. The role of the acetic acid is to keep the solution acidic enough to prevent the precipitation of iron oxide but low enough so that iron metal does not react with hydrogen ions. It is the high concentration of chloride that removes the rust not a "weak hydrochloric acid". How so exactly? Iron acetate is surely soluble enough? If one used a concentrated salt solution without the acetic acid then one would get a preciptate of hydrous iron oxide at the surface. This would slow the reaction to a crawl. Um, surely without the hydrogen ions, you are not going to get any dissolution of anything in the first place. All you need is an anion along with the H+ that does not form an insoluble precipitate with the resulting iron ions. A weak acid such as acetic acid allows one to put a lot of acid in the solution but maintain a relatively low hydrogen concentration. Yep, that's what "weak" means wrt acids and bases. The solution if kept covered can be used repeatedly until the amount of dissolved iron reaches a point where the hydrous oxide begins to precipitate. Where you have infact neutralised all the acetic acid present. If the used solutions are left open to the air then it will accumulate ferric chloride as a result of air oxidation. No, it will remain a solution of iron ions, acetate ions, sodium ions and chloride ions. The iron ions will slowly precipitate to iron hydroxide complexes as the final H+ ions are used up. No? That ferric chloride is an oxidizing agent strong enough to react with iron metal which is the reason one gets an "etch line" at the liquid surface. Yes, if what you had was ferric chloride. You don't. You have a neutral solution of the ions I just mentioned, surely. |
|
#43
|
|||
|
|||
|
Salt and vinegar for rust removal
On Fri, 14 May 2004 06:02:58 -0500, Unknown
posted: On Fri, 14 May 2004 03:56:58 GMT, "Dan White" wrote: ,; ,;"Unknown" wrote in message m... ,; On Thu, 13 May 2004 09:04:26 -0700, Larry Blanchard ,; wrote: ,; ,; ,;In article , ,; says... ,; ,; Ditto! All I can say is that the presence of ions in solution, ionic ,; ,; strength, does definitely affect how species in solution react. ,;Maybe there ,; ,; is some physical chemistry website or ng you can visit and ask this ,; ,; question. I'd be interested to know, too! ,; ,; ,; ,;Wow! I didn't mean to start such a learned discussion :-). My ,; ,;knowledge of chemistry is limited to making various explosive ,; ,;compounds, learned long ago in my juvenile days. And lately, I ,; ,;think I've forgotten most of that - CRS seting in :-). ,; ,; ,; ,;But what I meant by "ask a chemist" is that a friend of mine who ,; ,;is a chemist said that the vinegar and salt combined to form a ,; ,;weak hydrochloric acid. I took his word for it. ,; ,; You shouldn't have as he was wrong. ,; ,; Vinegar is approximately 5% acetic acid plus some other goodies to ,; provide some taste. The hydrogen ion concentration is not sufficient ,; to react with metallic iron and therein lies one of the keys to the ,; process. The other key is the fact that chloride ions form a stable ,; complex with iron ions in solution. The iron chloride complex is ,; strong enough so that iron oxide will dissolve and form that complex. ,; Since there is no oxidant strong enough to react with iron metal the ,; net result is that the iron oxide goes into solution as the chloride ,; but the iron metal does not react. ,; ,;Can you explain exactly what this iron-chloride complex is? Are you saying ,;that the iron oxide (rust) is preferentially breaking it's molecular bonds ,;and is reforming as some kind of complex, or as iron chloride? I take it ,;that it is not iron chloride because you say below that if oxygen is ,;introduced, then ferric chloride will form. Second question: What is the ,;reaction that transforms this "iron chloride complex" into ferric chloride? Both ferrous ions and ferric ions form stable chloride complexes. Much like stable acetate complexes? Stable enough so that the rust does dissolve in the strong chloride solution by breaking iron-oxygen bonds. Just like in acetic acid solutions? When the rust dissolves in a chloride solution Where does this ever happen? Surely the rust dissolves in a solution of H+ with a non-precipitating anion? one will get a solution which contains both species. In the presence of metallic iron the ferric chloride (from dissolution of iron III in rust) will be reduced to ferrous chloride so when the reaction is done we have a ferrous chloride in solution. If one adds oxygen (from air) then the ferrous is oxidized to ferric and this ferric immediately reacts with the metallic iron. The result is that one dissolves more metallic iron than is necessary and probably more than one wants. Yep, the acidic solutioss speed up the atmospheric corrosion process. In general you don't usually find three different oxidation states of an element present in solution at the same time. The highest oxidation state (ferric in this case) tends to react with the lowest (iron metal) to equilibrate with the one in the middle (ferrous). If you keep adding more air to form more ferric it should be obvious that the above reaction will continue until you run out of iron or oxygen. You can run out of oxygen by keeping the pot covered and the piece immersed. Yep. Basic measures to stop atmospheric corrosion. Usually the quantity of rust dissolved is small in comparisons to the mass of iron metal so one doesn't notice the fact that some iron metal is sacrificed in this procedure. Which is why I personally would prefer mechanical derusting procedures in ethe medium of non-polar solvents that tend to prevent further corrosion. If you allow air into the mix the effect of dissolved oxygen can be very apparent. You can demonstrate this by letting a piece of iron be partially immersed in the solution. You will get an etch line at the liquid surface. If it is some antique you are restoring this etch line will not be a pleasant sight and will be almost impossible to fix. Yep! Sad! ,;Your mechanisms sound interesting, but it's hard to know if this is the ,;actual path without knowing the driving forces mathematically. It is nice that the correct chemistry is also interesting. Isn't the correct chemistry always the most interesting?  If you need the math lookup some coordination chemistry text books at a technical library. The topic is probably not of that much interest for this group. Google "coordination chemistry" with the quotes will give you a good start. Probably more than you ever wanted to know. Ayup. ,;dwhite ,; ,; ,; ,; ,; It is essential that the solution be kept oxygen free or the metal ,; will dissolve. This is particularly noticeable if you allow the metal ,; to be "derusted" to stick out of the solution into air e.g. you will ,; find that there has been a dissolution of iron metal at the air liquid ,; interface. ,; ,; The role of the acetic acid is to keep the solution acidic enough to ,; prevent the precipitation of iron oxide but low enough so that iron ,; metal does not react with hydrogen ions. It is the high concentration ,; of chloride that removes the rust not a "weak hydrochloric acid". ,; ,; If one used a concentrated salt solution without the acetic acid then ,; one would get a preciptate of hydrous iron oxide at the surface. This ,; would slow the reaction to a crawl. ,; ,; A weak acid such as acetic acid allows one to put a lot of acid in the ,; solution but maintain a relatively low hydrogen concentration. ,; ,; The solution if kept covered can be used repeatedly until the amount ,; of dissolved iron reaches a point where the hydrous oxide begins to ,; precipitate. If the used solutions are left open to the air then it ,; will accumulate ferric chloride as a result of air oxidation. That ,; ferric chloride is an oxidizing agent strong enough to react with iron ,; metal which is the reason one gets an "etch line" at the liquid ,; surface. ,; ,; ,; |
|
#44
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy wrote:
On Thu, 13 May 2004 22:15:37 -0500, Unknown posted: On Thu, 13 May 2004 09:04:26 -0700, Larry Blanchard wrote: ,;In article , says... ,; Ditto! All I can say is that the presence of ions in solution, ionic ,; strength, does definitely affect how species in solution react. Maybe there ,; is some physical chemistry website or ng you can visit and ask this ,; question. I'd be interested to know, too! ,; ,;Wow! I didn't mean to start such a learned discussion :-). My ,;knowledge of chemistry is limited to making various explosive ,;compounds, learned long ago in my juvenile days. And lately, I ,;think I've forgotten most of that - CRS seting in :-). ,; ,;But what I meant by "ask a chemist" is that a friend of mine who ,;is a chemist said that the vinegar and salt combined to form a ,;weak hydrochloric acid. I took his word for it. You shouldn't have as he was wrong. Vinegar is approximately 5% acetic acid plus some other goodies to provide some taste. The hydrogen ion concentration is not sufficient to react with metallic iron and therein lies one of the keys to the process. The other key is the fact that chloride ions form a stable complex with iron ions in solution. The iron chloride complex is strong enough so that iron oxide will dissolve and form that complex. Since there is no oxidant strong enough to react with iron metal the net result is that the iron oxide goes into solution as the chloride but the iron metal does not react. It is essential that the solution be kept oxygen free or the metal will dissolve. This is particularly noticeable if you allow the metal to be "derusted" to stick out of the solution into air e.g. you will find that there has been a dissolution of iron metal at the air liquid interface. The role of the acetic acid is to keep the solution acidic enough to prevent the precipitation of iron oxide but low enough so that iron metal does not react with hydrogen ions. It is the high concentration of chloride that removes the rust not a "weak hydrochloric acid". How so exactly? Iron acetate is surely soluble enough? If one used a concentrated salt solution without the acetic acid then one would get a preciptate of hydrous iron oxide at the surface. This would slow the reaction to a crawl. Um, surely without the hydrogen ions, you are not going to get any dissolution of anything in the first place. All you need is an anion along with the H+ that does not form an insoluble precipitate with the resulting iron ions. A weak acid such as acetic acid allows one to put a lot of acid in the solution but maintain a relatively low hydrogen concentration. Yep, that's what "weak" means wrt acids and bases. The solution if kept covered can be used repeatedly until the amount of dissolved iron reaches a point where the hydrous oxide begins to precipitate. Where you have infact neutralised all the acetic acid present. If the used solutions are left open to the air then it will accumulate ferric chloride as a result of air oxidation. No, it will remain a solution of iron ions, acetate ions, sodium ions and chloride ions. The iron ions will slowly precipitate to iron hydroxide complexes as the final H+ ions are used up. No? That ferric chloride is an oxidizing agent strong enough to react with iron metal which is the reason one gets an "etch line" at the liquid surface. Yes, if what you had was ferric chloride. You don't. You have a neutral solution of the ions I just mentioned, surely. You keep asking this question over and over. First, if you have ions they are not "neutral". By definition an ion is electrically charged, hence it is reactive. The solution is neutral because for each cation there is a matching anion with the opposite charge, but the ions themselves are not neutral at all. Second, chlorine is one of the most reactive of all elements, hence any reaction involving chlorine will proceed at a higher rate than one involving acetate. The end result is that by putting some chlorine ions in the solution you end up with a faster reaction. -- --John Reply to jclarke at ae tee tee global dot net (was jclarke at eye bee em dot net) |
|
#45
|
|||
|
|||
|
Salt and vinegar for rust removal
On Sun, 16 May 2004 23:21:33 -0400, "J. Clarke"
posted: Sandy wrote: On Thu, 13 May 2004 22:15:37 -0500, Unknown posted: On Thu, 13 May 2004 09:04:26 -0700, Larry Blanchard wrote: ,;In article , says... ,; Ditto! All I can say is that the presence of ions in solution, ionic ,; strength, does definitely affect how species in solution react. Maybe there ,; is some physical chemistry website or ng you can visit and ask this ,; question. I'd be interested to know, too! ,; ,;Wow! I didn't mean to start such a learned discussion :-). My ,;knowledge of chemistry is limited to making various explosive ,;compounds, learned long ago in my juvenile days. And lately, I ,;think I've forgotten most of that - CRS seting in :-). ,; ,;But what I meant by "ask a chemist" is that a friend of mine who ,;is a chemist said that the vinegar and salt combined to form a ,;weak hydrochloric acid. I took his word for it. You shouldn't have as he was wrong. Vinegar is approximately 5% acetic acid plus some other goodies to provide some taste. The hydrogen ion concentration is not sufficient to react with metallic iron and therein lies one of the keys to the process. The other key is the fact that chloride ions form a stable complex with iron ions in solution. The iron chloride complex is strong enough so that iron oxide will dissolve and form that complex. Since there is no oxidant strong enough to react with iron metal the net result is that the iron oxide goes into solution as the chloride but the iron metal does not react. It is essential that the solution be kept oxygen free or the metal will dissolve. This is particularly noticeable if you allow the metal to be "derusted" to stick out of the solution into air e.g. you will find that there has been a dissolution of iron metal at the air liquid interface. The role of the acetic acid is to keep the solution acidic enough to prevent the precipitation of iron oxide but low enough so that iron metal does not react with hydrogen ions. It is the high concentration of chloride that removes the rust not a "weak hydrochloric acid". How so exactly? Iron acetate is surely soluble enough? If one used a concentrated salt solution without the acetic acid then one would get a preciptate of hydrous iron oxide at the surface. This would slow the reaction to a crawl. Um, surely without the hydrogen ions, you are not going to get any dissolution of anything in the first place. All you need is an anion along with the H+ that does not form an insoluble precipitate with the resulting iron ions. A weak acid such as acetic acid allows one to put a lot of acid in the solution but maintain a relatively low hydrogen concentration. Yep, that's what "weak" means wrt acids and bases. The solution if kept covered can be used repeatedly until the amount of dissolved iron reaches a point where the hydrous oxide begins to precipitate. Where you have infact neutralised all the acetic acid present. If the used solutions are left open to the air then it will accumulate ferric chloride as a result of air oxidation. No, it will remain a solution of iron ions, acetate ions, sodium ions and chloride ions. The iron ions will slowly precipitate to iron hydroxide complexes as the final H+ ions are used up. No? That ferric chloride is an oxidizing agent strong enough to react with iron metal which is the reason one gets an "etch line" at the liquid surface. Yes, if what you had was ferric chloride. You don't. You have a neutral solution of the ions I just mentioned, surely. You keep asking this question over and over. Perhaps because I've not seen a satisfactory answer yet, and the person who wrote that article quoted, has asked to state the query again? First, if you have ions they are not "neutral". Huh? Sodium chloride solution is neutral. By definition an ion is electrically charged, hence it is reactive. Got nothing to do with chemical neutrality, sorry. The solution is neutral because for each cation there is a matching anion with the opposite charge, but the ions themselves are not neutral at all. I never said ions were neutral -- I was talking about the solution. The solution MUST be electrically neutral, but chemical neutrality has to do with balance between H+ and OH- in the solution. Second, chlorine is one of the most reactive of all elements, There is NO elemental chorine involved, sorry. hence any reaction involving chlorine will proceed at a higher rate than one involving acetate. See above. The chloride ion is arguably more stable than the acetate ion. The end result is that by putting some chlorine ions in the solution you end up with a faster reaction. Sorry, your premises are wrong so your conclusion is not sound. |
|
#46
|
|||
|
|||
|
Salt and vinegar for rust removal
"Unknown" wrote in message ... On Fri, 14 May 2004 16:30:02 GMT, "Dan White" wrote: ,; ,;"Charles Erskine" wrote in message e.com... ,; More than you probably wanted to know: ,; ,; http://yarchive.net/metal/rust_remove.html ,; ,; snip ,; ,;This is the post I pasted in this thread originally to try and answer the ,;original question. OK I missed your original post. I wrote the article you refer to. I am a chemist and do know what is happening in this procedure so let's start fresh. What is it that needs more clarification on this topic? You ask the questions and I will try to give a reasonable explanation. I had a feeling you were the same person as the original post I pasted. Sandy had the original question and I was trying to help. The only thing I still don't understand is exactly what the "complex" is that drives the Fe203 to dissociate and reform this complex with Cl-. Is it some kind of hydrated Fe complexed with Cl-? thanks, dwhite |
|
#47
|
|||
|
|||
|
Salt and vinegar for rust removal
On Mon, 17 May 2004 04:44:41 GMT, "Dan White"
posted: "Unknown" wrote in message .. . On Fri, 14 May 2004 16:30:02 GMT, "Dan White" wrote: ,; ,;"Charles Erskine" wrote in message e.com... ,; More than you probably wanted to know: ,; ,; http://yarchive.net/metal/rust_remove.html ,; ,; snip ,; ,;This is the post I pasted in this thread originally to try and answer the ,;original question. OK I missed your original post. I wrote the article you refer to. I am a chemist and do know what is happening in this procedure so let's start fresh. What is it that needs more clarification on this topic? You ask the questions and I will try to give a reasonable explanation. I had a feeling you were the same person as the original post I pasted. Sandy had the original question and I was trying to help. The only thing I still don't understand is exactly what the "complex" is that drives the Fe203 to dissociate and reform this complex with Cl-. Is it some kind of hydrated Fe complexed with Cl-? thanks, dwhite Thanks Dan, that's my question exactly. I can't see the difference between a ferric chloride complex and a ferric acetate complex. The thing that drives the reaction in my understanding is 6H+ + Fe2O3 -- 2Fe+++ + 3H2O That formation of water is what moves the reaction to the right. For me, salt is just going to cause problems down the line when it sets up corrosion cells in the fine interstices of the previous rust pitting. Unless someone can show that it is invaluable in the derusting process with weak acids, I would advise to stay well away from it. As I said, I far prefer mechanical derusting with a non-polar solvent (kerosene or CRC) for anything valuable. YMMV |
|
#48
|
|||
|
|||
|
Salt and vinegar for rust removal
"Sandy" wrote in message ... On Mon, 17 May 2004 04:44:41 GMT, "Dan White" posted: "Unknown" wrote in message .. . On Fri, 14 May 2004 16:30:02 GMT, "Dan White" wrote: ,; ,;"Charles Erskine" wrote in message e.com... ,; More than you probably wanted to know: ,; ,; http://yarchive.net/metal/rust_remove.html ,; ,; snip ,; ,;This is the post I pasted in this thread originally to try and answer the ,;original question. OK I missed your original post. I wrote the article you refer to. I am a chemist and do know what is happening in this procedure so let's start fresh. What is it that needs more clarification on this topic? You ask the questions and I will try to give a reasonable explanation. I had a feeling you were the same person as the original post I pasted. Sandy had the original question and I was trying to help. The only thing I still don't understand is exactly what the "complex" is that drives the Fe203 to dissociate and reform this complex with Cl-. Is it some kind of hydrated Fe complexed with Cl-? thanks, dwhite Thanks Dan, that's my question exactly. I can't see the difference between a ferric chloride complex and a ferric acetate complex. The thing that drives the reaction in my understanding is 6H+ + Fe2O3 -- 2Fe+++ + 3H2O That formation of water is what moves the reaction to the right. For me, salt is just going to cause problems down the line when it sets up corrosion cells in the fine interstices of the previous rust pitting. Unless someone can show that it is invaluable in the derusting process with weak acids, I would advise to stay well away from it. As I said, I far prefer mechanical derusting with a non-polar solvent (kerosene or CRC) for anything valuable. YMMV Just 2 comments: 1. It may just be that my chemistry was so long ago, but I'm not sure of the usage of the term "complex" in this context. Are we calling an FeCl3 molecule a complex (I didn't think so)? My recollection is that a complex had more to do with Van der Walls forces attracting surrounding molecules such as the solvent to the ion or molecule in question, as if it were chelated or sequestered. What is the complex that results from the rust-chloride reaction? 2. You have to admit that the NaCl is greatly accelerating the reaction rate. Just do like I mentioned and sprinkle salt on a copper pan wetted with vinegar. You will see the fastest reaction where the salt is. It seems you are looking at this from the standpoint that salt does nothing, and are challenging someone to prove otherwise. I think we are both interested in the same thing, but maybe are looking at it from different standpoints. regards, dwhite |
|
#49
|
|||
|
|||
|
Salt and vinegar for rust removal
On Mon, 17 May 2004 05:29:09 GMT, "Dan White"
posted: "Sandy" wrote in message .. . On Mon, 17 May 2004 04:44:41 GMT, "Dan White" posted: "Unknown" wrote in message .. . On Fri, 14 May 2004 16:30:02 GMT, "Dan White" wrote: ,; ,;"Charles Erskine" wrote in message e.com... ,; More than you probably wanted to know: ,; ,; http://yarchive.net/metal/rust_remove.html ,; ,; snip ,; ,;This is the post I pasted in this thread originally to try and answer the ,;original question. OK I missed your original post. I wrote the article you refer to. I am a chemist and do know what is happening in this procedure so let's start fresh. What is it that needs more clarification on this topic? You ask the questions and I will try to give a reasonable explanation. I had a feeling you were the same person as the original post I pasted. Sandy had the original question and I was trying to help. The only thing I still don't understand is exactly what the "complex" is that drives the Fe203 to dissociate and reform this complex with Cl-. Is it some kind of hydrated Fe complexed with Cl-? thanks, dwhite Thanks Dan, that's my question exactly. I can't see the difference between a ferric chloride complex and a ferric acetate complex. The thing that drives the reaction in my understanding is 6H+ + Fe2O3 -- 2Fe+++ + 3H2O That formation of water is what moves the reaction to the right. For me, salt is just going to cause problems down the line when it sets up corrosion cells in the fine interstices of the previous rust pitting. Unless someone can show that it is invaluable in the derusting process with weak acids, I would advise to stay well away from it. As I said, I far prefer mechanical derusting with a non-polar solvent (kerosene or CRC) for anything valuable. YMMV Just 2 comments: 1. It may just be that my chemistry was so long ago, but I'm not sure of the usage of the term "complex" in this context. Are we calling an FeCl3 molecule a complex (I didn't think so)? I guess it might be some sort of hydrated "complex". Like most ionic species in aqueous solution. Our understanding of "complexes" seems to coincide, although that's possibly and artifact of the age of our chemistry learning (me ~ 45 years My recollection is that a complex had more to do with Van der Walls forces attracting surrounding molecules such as the solvent to the ion or molecule in question, as if it were chelated or sequestered. What is the complex that results from the rust-chloride reaction? That's the nub, I suspect, and why it is purportedly different from a similar acetate "complex". 2. You have to admit that the NaCl is greatly accelerating the reaction rate. I can't disagree with you here, (never having tried it), but have difficulty in explaining it to myself. I just hate salt!! It has screwed up masses of our ag land and costs society squillions in damage to just about everything. If it can be avoided, I will avoid it. I once had a car at the beach where the radiator fell apart on the outside (all the fins disappeared) while the inside was perfect. Just do like I mentioned and sprinkle salt on a copper pan wetted with vinegar. You will see the fastest reaction where the salt is. It seems you are looking at this from the standpoint that salt does nothing, and are challenging someone to prove otherwise. Well no, but then copper is a different kettle of fish, being on the other side of hydrogen in the electrochemical reactivity series. Next time my wife asks me to get rid of some rust stains, and I have no CLR (another weak organic acid sold for the purpose of removing lime deposits and rust stains) I will try acetic acid with NaCl and without. Stop watch and clip board at the ready! I think we are both interested in the same thing, but maybe are looking at it from different standpoints. Or fairly similar standpoints. I see the downside of introducing salt to rusted metal, having lived near the beach for a long time. |
|
#50
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy wrote:
On Sun, 16 May 2004 23:21:33 -0400, "J. Clarke" posted: Sandy wrote: On Thu, 13 May 2004 22:15:37 -0500, Unknown posted: On Thu, 13 May 2004 09:04:26 -0700, Larry Blanchard wrote: ,;In article , says... ,; Ditto! All I can say is that the presence of ions in solution, ionic ,; strength, does definitely affect how species in solution react. Maybe there ,; is some physical chemistry website or ng you can visit and ask this ,; question. I'd be interested to know, too! ,; ,;Wow! I didn't mean to start such a learned discussion :-). My ,;knowledge of chemistry is limited to making various explosive ,;compounds, learned long ago in my juvenile days. And lately, I ,;think I've forgotten most of that - CRS seting in :-). ,; ,;But what I meant by "ask a chemist" is that a friend of mine who ,;is a chemist said that the vinegar and salt combined to form a ,;weak hydrochloric acid. I took his word for it. You shouldn't have as he was wrong. Vinegar is approximately 5% acetic acid plus some other goodies to provide some taste. The hydrogen ion concentration is not sufficient to react with metallic iron and therein lies one of the keys to the process. The other key is the fact that chloride ions form a stable complex with iron ions in solution. The iron chloride complex is strong enough so that iron oxide will dissolve and form that complex. Since there is no oxidant strong enough to react with iron metal the net result is that the iron oxide goes into solution as the chloride but the iron metal does not react. It is essential that the solution be kept oxygen free or the metal will dissolve. This is particularly noticeable if you allow the metal to be "derusted" to stick out of the solution into air e.g. you will find that there has been a dissolution of iron metal at the air liquid interface. The role of the acetic acid is to keep the solution acidic enough to prevent the precipitation of iron oxide but low enough so that iron metal does not react with hydrogen ions. It is the high concentration of chloride that removes the rust not a "weak hydrochloric acid". How so exactly? Iron acetate is surely soluble enough? If one used a concentrated salt solution without the acetic acid then one would get a preciptate of hydrous iron oxide at the surface. This would slow the reaction to a crawl. Um, surely without the hydrogen ions, you are not going to get any dissolution of anything in the first place. All you need is an anion along with the H+ that does not form an insoluble precipitate with the resulting iron ions. A weak acid such as acetic acid allows one to put a lot of acid in the solution but maintain a relatively low hydrogen concentration. Yep, that's what "weak" means wrt acids and bases. The solution if kept covered can be used repeatedly until the amount of dissolved iron reaches a point where the hydrous oxide begins to precipitate. Where you have infact neutralised all the acetic acid present. If the used solutions are left open to the air then it will accumulate ferric chloride as a result of air oxidation. No, it will remain a solution of iron ions, acetate ions, sodium ions and chloride ions. The iron ions will slowly precipitate to iron hydroxide complexes as the final H+ ions are used up. No? That ferric chloride is an oxidizing agent strong enough to react with iron metal which is the reason one gets an "etch line" at the liquid surface. Yes, if what you had was ferric chloride. You don't. You have a neutral solution of the ions I just mentioned, surely. You keep asking this question over and over. Perhaps because I've not seen a satisfactory answer yet, and the person who wrote that article quoted, has asked to state the query again? First, if you have ions they are not "neutral". Huh? Sodium chloride solution is neutral. By definition an ion is electrically charged, hence it is reactive. Got nothing to do with chemical neutrality, sorry. The solution is neutral because for each cation there is a matching anion with the opposite charge, but the ions themselves are not neutral at all. I never said ions were neutral -- I was talking about the solution. The solution MUST be electrically neutral, but chemical neutrality has to do with balance between H+ and OH- in the solution. "The solution" is not what reacts with the rust. What reacts with the rust is individual ions within that solution. Second, chlorine is one of the most reactive of all elements, There is NO elemental chorine involved, sorry. So what is a chlorine ion floating around with its electrical charge exposed if not "elemental chlorine"? What comes in contact with the rust is not sodium and chlorine bound, it's individual sodium ions and individual chlorine ions. hence any reaction involving chlorine will proceed at a higher rate than one involving acetate. See above. The chloride ion is arguably more stable than the acetate ion. I thought we were talking chemistry here, not physics. A monatomic ion is not "stable" or "unstable" chemically--that's a property of a compound. The end result is that by putting some chlorine ions in the solution you end up with a faster reaction. Sorry, your premises are wrong so your conclusion is not sound. No, your understanding of what constitutes an ion is so wrong that you can't follow the argument. -- --John Reply to jclarke at ae tee tee global dot net (was jclarke at eye bee em dot net) |
|
#51
|
|||
|
|||
|
Salt and vinegar for rust removal
On Mon, 17 May 2004 06:40:06 -0400, "J. Clarke"
posted: Sandy wrote: On Sun, 16 May 2004 23:21:33 -0400, "J. Clarke" posted: Sandy wrote: On Thu, 13 May 2004 22:15:37 -0500, Unknown posted: On Thu, 13 May 2004 09:04:26 -0700, Larry Blanchard wrote: ,;In article , says... ,; Ditto! All I can say is that the presence of ions in solution, ionic ,; strength, does definitely affect how species in solution react. Maybe there ,; is some physical chemistry website or ng you can visit and ask this ,; question. I'd be interested to know, too! ,; ,;Wow! I didn't mean to start such a learned discussion :-). My ,;knowledge of chemistry is limited to making various explosive ,;compounds, learned long ago in my juvenile days. And lately, I ,;think I've forgotten most of that - CRS seting in :-). ,; ,;But what I meant by "ask a chemist" is that a friend of mine who ,;is a chemist said that the vinegar and salt combined to form a ,;weak hydrochloric acid. I took his word for it. You shouldn't have as he was wrong. Vinegar is approximately 5% acetic acid plus some other goodies to provide some taste. The hydrogen ion concentration is not sufficient to react with metallic iron and therein lies one of the keys to the process. The other key is the fact that chloride ions form a stable complex with iron ions in solution. The iron chloride complex is strong enough so that iron oxide will dissolve and form that complex. Since there is no oxidant strong enough to react with iron metal the net result is that the iron oxide goes into solution as the chloride but the iron metal does not react. It is essential that the solution be kept oxygen free or the metal will dissolve. This is particularly noticeable if you allow the metal to be "derusted" to stick out of the solution into air e.g. you will find that there has been a dissolution of iron metal at the air liquid interface. The role of the acetic acid is to keep the solution acidic enough to prevent the precipitation of iron oxide but low enough so that iron metal does not react with hydrogen ions. It is the high concentration of chloride that removes the rust not a "weak hydrochloric acid". How so exactly? Iron acetate is surely soluble enough? If one used a concentrated salt solution without the acetic acid then one would get a preciptate of hydrous iron oxide at the surface. This would slow the reaction to a crawl. Um, surely without the hydrogen ions, you are not going to get any dissolution of anything in the first place. All you need is an anion along with the H+ that does not form an insoluble precipitate with the resulting iron ions. A weak acid such as acetic acid allows one to put a lot of acid in the solution but maintain a relatively low hydrogen concentration. Yep, that's what "weak" means wrt acids and bases. The solution if kept covered can be used repeatedly until the amount of dissolved iron reaches a point where the hydrous oxide begins to precipitate. Where you have infact neutralised all the acetic acid present. If the used solutions are left open to the air then it will accumulate ferric chloride as a result of air oxidation. No, it will remain a solution of iron ions, acetate ions, sodium ions and chloride ions. The iron ions will slowly precipitate to iron hydroxide complexes as the final H+ ions are used up. No? That ferric chloride is an oxidizing agent strong enough to react with iron metal which is the reason one gets an "etch line" at the liquid surface. Yes, if what you had was ferric chloride. You don't. You have a neutral solution of the ions I just mentioned, surely. You keep asking this question over and over. Perhaps because I've not seen a satisfactory answer yet, and the person who wrote that article quoted, has asked to state the query again? First, if you have ions they are not "neutral". Huh? Sodium chloride solution is neutral. By definition an ion is electrically charged, hence it is reactive. Got nothing to do with chemical neutrality, sorry. The solution is neutral because for each cation there is a matching anion with the opposite charge, but the ions themselves are not neutral at all. I never said ions were neutral -- I was talking about the solution. The solution MUST be electrically neutral, but chemical neutrality has to do with balance between H+ and OH- in the solution. "The solution" is not what reacts with the rust. What reacts with the rust is individual ions within that solution. So? What ions are you claiming react with the rust (other than H+)? Can you give balanced equations for this? Second, chlorine is one of the most reactive of all elements, There is NO elemental chorine involved, sorry. So what is a chlorine ion floating around with its electrical charge exposed if not "elemental chlorine"? A chlorine ion! Elemental chlorine with an extra electron! And electrons are what give chemical moieties their chemical properties. What comes in contact with the rust is not sodium and chlorine bound, it's individual sodium ions and individual chlorine ions. Which apparently have no effect? The dissolution/neutralisation of Fe2O3 is by H+ ions, surely. hence any reaction involving chlorine will proceed at a higher rate than one involving acetate. See above. The chloride ion is arguably more stable than the acetate ion. I thought we were talking chemistry here, not physics. I am talking chemistry. What are you referring to? A monatomic ion is not "stable" or "unstable" chemically--that's a property of a compound. Why? A chloride ion is more stable (less likely to change its chemical state) than an acetate ion. A fluoride ion is even MORE stable! Elemental chlorine and fluorine are most UNSTABLE. Stability is, afterall, the ability to resist (chemical) change. The end result is that by putting some chlorine ions in the solution you end up with a faster reaction. Sorry, your premises are wrong so your conclusion is not sound. No, your understanding of what constitutes an ion is so wrong that you can't follow the argument. Ummm, OK. Could you explain then what constitutes and ion? There is no argument. What we need explaining is why the presence of sodium chloride in the vinegar is advantageous. |
|
#52
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy writes:
Why? A chloride ion is more stable (less likely to change its chemical state) than an acetate ion. A fluoride ion is even MORE stable! Elemental chlorine and fluorine are most UNSTABLE. Stability is, afterall, the ability to resist (chemical) change. The end result is that by putting some chlorine ions in the solution you end up with a faster reaction. Sorry, your premises are wrong so your conclusion is not sound. No, your understanding of what constitutes an ion is so wrong that you can't follow the argument. Ummm, OK. Could you explain then what constitutes and ion? There is no argument. What we need explaining is why the presence of sodium chloride in the vinegar is advantageous. Nah. What we need to know is whether or not it WORKS. I, like most woodwrkers, am not a chemist. Like most woodworkers, I have some tools that I either buy with rust on them, or that are particularly susceptible to rust under certain conditions. Somewhere about 5 posts ago, an OT should have been added to this thread. Charlie Self "Bore, n.: A person who talks when you wish him to listen." Ambrose Bierce, The Devil's Dictionary |
|
#53
|
|||
|
|||
|
Salt and vinegar for rust removal
On Mon, 17 May 2004 04:44:41 GMT, "Dan White"
wrote: ,; ,;"Unknown" wrote in message ... ,; On Fri, 14 May 2004 16:30:02 GMT, "Dan White" ,; wrote: ,; ,; ,; ,; ,;"Charles Erskine" wrote in message ,; e.com... ,; ,; More than you probably wanted to know: ,; ,; ,; ,; http://yarchive.net/metal/rust_remove.html ,; ,; ,; ,; snip ,; ,; ,; ,;This is the post I pasted in this thread originally to try and answer ,;the ,; ,;original question. ,; ,; OK I missed your original post. I wrote the article you refer to. I am ,; a chemist and do know what is happening in this procedure so let's ,; start fresh. ,; ,; What is it that needs more clarification on this topic? You ask the ,; questions and I will try to give a reasonable explanation. ,; ,;I had a feeling you were the same person as the original post I pasted. ,;Sandy had the original question and I was trying to help. The only thing I ,;still don't understand is exactly what the "complex" is that drives the ,;Fe203 to dissociate and reform this complex with Cl-. Is it some kind of ,;hydrated Fe complexed with Cl-? If the rust is present as Fe203 then the iron is trivalent and will go into the salt-acetic acid solution predominately as the FeCl6(-3) complex. Note that there is no change in oxidation state of the iron. That iron complex is a central trivalent iron ion (with a +3 charge) which usually has a coordination number of six. That means there will be six positions around that iron ion that are occupied by some species. Since the concentration of chloride is so high relative to the other anions the predominate species will be FeCl6(-3). The net charge of the complex is -3 because each chloride carries a -1 charge and the iron has a +3 charge. There certainly will be some anions where an acetate ion and/or a hydroxyl ion will replace one or more of the chlorides. For this discussion the exact composition of that iron complex is not only unknown but is of no particular interest. Just remember that if too many of the chlorides in that complex are replaced by hydroxyls or acetates then the iron will precipitate as a hydrous oxide or basic acetate and that is why one uses such a high concentration of chloride. It is the stability of that iron chloride complex and the whopping excess of chloride ions that drives this reaction. The high solubility of iron chlorides prevents the reaction from coming to a screeching halt due to precipitated of hydrous iron oxides and basic acetates. There is no oxidation or reduction reaction at this point. That iron complex will oxidize iron metal. The simplified net reaction is 2Fe+3 + Fe(0) -- 3Fe+2 This reaction is one that you don't want to happen because that Fe(0) is the iron metal you presumably are trying to recover rust free. This also should suggest to you why you should keep oxygen (air) out of the solution. Fe+2 is oxidized to Fe+3 by oxygen and the reaction takes place readily because of the stability of the iron(III)-chloride complex. If you allow air into the process you will be producing more Fe+3 which in turn reacts with the iron metal (see the above reaction). If you bubbled air through the solution this process will continue until you run out of iron metal or the process gets bogged down by precipitation. It is this reaction which will give you an etch line at the liquid surface. Why?...because that is where the oxygen is. This process works well with Fe203, less well with Fe304. Since the concern about using chloride has been mentioned I will address that issue as well. The chloride will be pretty well rinsed off of the surface. The freshly cleaned iron surface is quite reactive and needs some type of protection. If you keep iron dry it won't rust. WD-40 is not a good option as it will pick up water. Chloride can remain in microscopic cracks where it can accelerate stress corrosion. If you are cleaning up an I-beam for a bridge this process might not be a good choice. If you are cleaning a wrench e.g. that is not an antique I wouldn't worry about stress corrosion. If I am cleaning some tool that the kids left out in the rain I probably will dunk it in a 5% solution of muriatic acid, rinse it and apply a light wax. If you have a valuable antique get some advice from someone else as cleaning may not be appropriate. Why not use vinegar without the chloride? Vinegar is ~5% acetic acid. Now for a little of the requested math. The dissociation constant of HAc (acetic acid) is ~10^-5. (Ten to the minus five) In simplified terms the H+ concentration in solution times the Ac-1 equals ten to the minus five. Since the H+ = Ac-1 the acetate and the hydrogen ion concentration in 5% acetic acid will equal the square root of 10^-5 or somewhere around .02 molar. If someone wants to be picky it actually calculates to be a tad more concentrated. That concentration of hydrogen ions won't keep trivalent iron in solution. This thread has stirred up some interest. I will stick with it at least for a while. Let's see if this answers some of the questions or if I have everyone more confused. |
|
#54
|
|||
|
|||
|
Salt and vinegar for rust removal
|
|
#55
|
|||
|
|||
|
Salt and vinegar for rust removal
On Mon, 17 May 2004 07:10:31 -0500, Unknown
posted: On Mon, 17 May 2004 04:44:41 GMT, "Dan White" wrote: ,; ,;"Unknown" wrote in message m... ,; On Fri, 14 May 2004 16:30:02 GMT, "Dan White" ,; wrote: ,; ,; ,; ,; ,;"Charles Erskine" wrote in message ,; e.com... ,; ,; More than you probably wanted to know: ,; ,; ,; ,; http://yarchive.net/metal/rust_remove.html ,; ,; ,; ,; snip ,; ,; ,; ,;This is the post I pasted in this thread originally to try and answer ,;the ,; ,;original question. ,; ,; OK I missed your original post. I wrote the article you refer to. I am ,; a chemist and do know what is happening in this procedure so let's ,; start fresh. ,; ,; What is it that needs more clarification on this topic? You ask the ,; questions and I will try to give a reasonable explanation. ,; ,;I had a feeling you were the same person as the original post I pasted. ,;Sandy had the original question and I was trying to help. The only thing I ,;still don't understand is exactly what the "complex" is that drives the ,;Fe203 to dissociate and reform this complex with Cl-. Is it some kind of ,;hydrated Fe complexed with Cl-? If the rust is present as Fe203 then the iron is trivalent and will go into the salt-acetic acid solution predominately as the FeCl6(-3) complex. Note that there is no change in oxidation state of the iron. That iron complex is a central trivalent iron ion (with a +3 charge) which usually has a coordination number of six. That means there will be six positions around that iron ion that are occupied by some species. Since the concentration of chloride is so high relative to the other anions the predominate species will be FeCl6(-3). The net charge of the complex is -3 because each chloride carries a -1 charge and the iron has a +3 charge. There certainly will be some anions where an acetate ion and/or a hydroxyl ion will replace one or more of the chlorides. For this discussion the exact composition of that iron complex is not only unknown but is of no particular interest. Just remember that if too many of the chlorides in that complex are replaced by hydroxyls or acetates then the iron will precipitate as a hydrous oxide or basic acetate and that is why one uses such a high concentration of chloride. So with excess acetic acid present, "hydrous oxides or basic acetates" will be precipitated? Surely they will be redissolved by the excess acetic acid as soluble acetates? It is the stability of that iron chloride complex and the whopping excess of chloride ions that drives this reaction. What is formed from the stable soluble ferric acetate that is taken out of the process? If all this chloride is "taken out of the scene" what happens to all those lonely sodium ions? The high solubility of iron chlorides prevents the reaction from coming to a screeching halt due to precipitated of hydrous iron oxides and basic acetates. Surely excess acetic acid does the same thing? There is no oxidation or reduction reaction at this point. That iron complex will oxidize iron metal. The simplified net reaction is 2Fe+3 + Fe(0) -- 3Fe+2 Only when exposed to atmospheric oxygen, No? This reaction is one that you don't want to happen because that Fe(0) is the iron metal you presumably are trying to recover rust free. This also should suggest to you why you should keep oxygen (air) out of the solution. Yep. Fe+2 is oxidized to Fe+3 by oxygen and the reaction takes place readily because of the stability of the iron(III)-chloride complex. If you allow air into the process you will be producing more Fe+3 which in turn reacts with the iron metal (see the above reaction). If you bubbled air through the solution this process will continue until you run out of iron metal or the process gets bogged down by precipitation. It is this reaction which will give you an etch line at the liquid surface. Why?...because that is where the oxygen is. Yep. This process works well with Fe203, less well with Fe304. Magnetite is quite resistant to any attack. It usually just falls to the bottom as a black sludge IME. Since the concern about using chloride has been mentioned I will address that issue as well. The chloride will be pretty well rinsed off of the surface. The freshly cleaned iron surface is quite reactive and needs some type of protection. If you keep iron dry it won't rust. WD-40 is not a good option as it will pick up water. WD-40 surely repels water. I suggest that heavily pitted iron which has had salt solution soaking into the pits will be quite difficult to rinse clean. Chloride can remain in microscopic cracks where it can accelerate stress corrosion. That's what I said. I thought you were contradicting this above. If you are cleaning up an I-beam for a bridge this process might not be a good choice. If you are cleaning a wrench e.g. that is not an antique I wouldn't worry about stress corrosion. Further corrosion? I would certainly not want that. Wrenches in my hands suffer extreme stress. I've broken several If I am cleaning some tool that the kids left out in the rain I probably will dunk it in a 5% solution of muriatic acid, rinse it and apply a light wax. Hooley Dooley, how long will that last? What's wrong with a quick squirt of CRC or WD 40 and a wipe with a rag? If you have a valuable antique get some advice from someone else as cleaning may not be appropriate. And certainly don't use hydrochloric acid (shudder) or salt and vinegar. Save the latter for your fish and chips Why not use vinegar without the chloride? Vinegar is ~5% acetic acid. Now for a little of the requested math. The dissociation constant of HAc (acetic acid) is ~10^-5. (Ten to the minus five) In simplified terms the H+ concentration in solution times the Ac-1 equals ten to the minus five. Since the H+ = Ac-1 the acetate and the hydrogen ion concentration in 5% acetic acid will equal the square root of 10^-5 or somewhere around .02 molar. If someone wants to be picky it actually calculates to be a tad more concentrated. That concentration of hydrogen ions won't keep trivalent iron in solution. So you're saying that acetic acid won't dissolve Fe2O3? It does for me. The label of my vinegar does not list sodium chloride. This thread has stirred up some interest. I will stick with it at least for a while. Let's see if this answers some of the questions or if I have everyone more confused. I'm still struggling with your claim that ferric acetate in excess acetic acid is unstable. If you say that the sodium chloride keeps it in solution and stops it precipitaing out as ~ ferric hydroxide, then that is not my experience. I end up with a dirty yellow solution when I soak rust in vinegar. I have never used salt in the vinegar, but next time I have need to clean some rust, I will try with and without, to see if the claimed speed increase occurs, or you claim of precipitation of ferric hydroxide occurs and does not occur. Museums soak very rusty items in sodium hydroxide solutions. I believe this just stops further corrosion until the rust can be removed by other means. |
|
#56
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy responds:
Nah. What we need to know is whether or not it WORKS. Speak for yourself. If that satisfies you, then I'm happy for you Until you understand it, you won't know whether it works or not. Nonsense. What you're saying is that if you don't understand the mechanisms of flight, you don't know that there are aircraft overhead. Are woodworkers prevented from being chemists? I'm not a chemist, but I have wide interests in many areas. I know several chemists who are woodworkers. Will you tell them, or should I? Nothing to tell them. I know chemists, electrical engineers, computer programmers and a host of other tech types. So what? Where did I say that chemists shouldn't be woodworkers, incidentally? If they were mine, and I valued them, I would not use salt and vinegar on them. This comes from my understanding of chemistry. Well, I probably won't either, but that's because I have used electrolysis for years. Somewhere about 5 posts ago, an OT should have been added to this thread. Why? Is it not pertinent to restoring woodworking tools? I suggest you are being selfish How is a thread on ionization and covalents and whatever else pertinent to restoring woodworking tools? It won't matter to me, as I've just trashed this thread, but the fact is, none of you seems capable of snipping, and there is absolutely no way for an average woodworker to tell which of you guys is full of beans, so there's not much value here to the woodworker. It remains a choice that may or may not work. And that may or may not damage tools because of the presence of salt. Depends on which of you a person chooses to believe, because there has been no coherent and definitive explanation by anyone. If that makes me selfish, so be it. If you think that's a new cutesy on my name, then you're about 400 years behind the times there. Charlie Self "Bore, n.: A person who talks when you wish him to listen." Ambrose Bierce, The Devil's Dictionary |
|
#57
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy wrote:
On 17 May 2004 12:06:40 GMT, otforme (Charlie Self) There is no argument. What we need explaining is why the presence of sodium chloride in the vinegar is advantageous. Nah. What we need to know is whether or not it WORKS. Speak for yourself. If that satisfies you, then I'm happy for you Until you understand it, you won't know whether it works or not. Disagree. One can observe a cause and effect repeatedly and draw valid conclusions without understanding the mechanism. Folks knew that dropping a stone on their foot would hurt long before Newton and an understanding of the nervous system (and do we yet fully understand the mechanism of gravity, or just have more sophisticated observations about it?) Charlie's point is valid; all we NEED to know is whether it works. I'm with you in fascination with understanding why it works, but that understanding is a want more than a need. I, like most woodwrkers, am not a chemist. Are woodworkers prevented from being chemists? Reread the sentence you quoted. I'm not a chemist, but I have wide interests in many areas. I know several chemists who are woodworkers. Will you tell them, or should I? Tell them what? That most woodworkers are not chemists? You tell them. I hate the "you idiot" stares I sometimes get when stating the obvious. Like most woodworkers, I have some tools that I either buy with rust on them, or that are particularly susceptible to rust under certain conditions. If they were mine, and I valued them, I would not use salt and vinegar on them. This comes from my understanding of chemistry. Why? What are the bad effects predicted by your understanding of chemistry, and do they prove out in practice? Somewhere about 5 posts ago, an OT should have been added to this thread. Why? Is it not pertinent to restoring woodworking tools? Yes. I agree that it is not OT. I suggest you are being selfish I suggest that he is stating his interest. -- Alex Make the obvious change in the return address to reply by email. |
|
#58
|
|||
|
|||
|
Salt and vinegar for rust removal
|
|
#59
|
|||
|
|||
|
Salt and vinegar for rust removal
On Mon, 17 May 2004 13:39:46 GMT, alexy
posted: Sandy wrote: On 17 May 2004 12:06:40 GMT, otforme (Charlie Self) There is no argument. What we need explaining is why the presence of sodium chloride in the vinegar is advantageous. Nah. What we need to know is whether or not it WORKS. Speak for yourself. If that satisfies you, then I'm happy for you Until you understand it, you won't know whether it works or not. Disagree. One can observe a cause and effect repeatedly and draw valid conclusions without understanding the mechanism. Disagree. If you don't understand the mechanism, or the rationale, you are very likely to cock it up when things don't go exactly as expected. Especially with complex procedures. That's why they teach theory in all trade courses. Folks knew that dropping a stone on their foot would hurt long before Newton and an understanding of the nervous system (and do we yet fully understand the mechanism of gravity, or just have more sophisticated observations about it?) Charlie's point is valid; all we NEED to know is whether it works. And does it? Charlie will likely never be quite sure. Someone has to figure out how it works to be able to do it competently. Not much is likely to go wrong with your strange hobby of dropping rocks on your foot, I would have thought. Now chemical procedures... I'm with you in fascination with understanding why it works, but that understanding is a want more than a need. Again I disagree. So many things can go wrong with things chemical. So many things waiting to bite you on the ass. DAMHIKT. I, like most woodwrkers, am not a chemist. Are woodworkers prevented from being chemists? Reread the sentence you quoted. Yes, and what point is it trying to make? Charlie is not a chemist, so woodworkers don't need to know any chemistry? Well if that's how he feels, why is he whining about our discussion about derusting tools? I'm not a chemist, but I have wide interests in many areas. I know several chemists who are woodworkers. Will you tell them, or should I? Tell them what? That most woodworkers are not chemists? You tell them. I hate the "you idiot" stares I sometimes get when stating the obvious. See above. Like most woodworkers, I have some tools that I either buy with rust on them, or that are particularly susceptible to rust under certain conditions. If they were mine, and I valued them, I would not use salt and vinegar on them. This comes from my understanding of chemistry. Why? What are the bad effects predicted by your understanding of chemistry, and do they prove out in practice? Yep. Salt will enter the fine pits and interstices of the corroded surface and perpetuate future corrosion. Very difficult to clean thoroughly. There was a guy once who ignored chemistry and shot-blasted his aluminium boat with copper shot. It lasted but a few weeks. Chemistry is VERY important! Somewhere about 5 posts ago, an OT should have been added to this thread. Why? Is it not pertinent to restoring woodworking tools? Yes. I agree that it is not OT. So Charlie is being selfish in complaining about the discussion we are having? I suggest you are being selfish I suggest that he is stating his interest. Why? In a thread that he is complaining about being irrelevant? Sounds like "dog in the manger" to me. |
|
#60
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy wrote:
Disagree. One can observe a cause and effect repeatedly and draw valid conclusions without understanding the mechanism. Disagree. If you don't understand the mechanism, or the rationale, you are very likely to cock it up when things don't go exactly as expected. Especially with complex procedures. LOL! Do you really think that the inorganic chemistry involved in the derusting process is more complex than the operation of the gravitational force and the organic chemistry and electrical processes involved in the sensing, transmittal, and interpretation of the pain signal? Understanding theory does help immensely, when deviating from experience, but empirical evidence can be adequate for some instances, such as derusting some particular steel. Where I see theoretical knowledge of the mechanism helping is knowing how it might work on a different alloy, how different solutions might work if the known one is not available, predicting long-term effects if evidence is not available, etc. Folks knew that dropping a stone on their foot would hurt long before Newton and an understanding of the nervous system (and do we yet fully understand the mechanism of gravity, or just have more sophisticated observations about it?) Charlie's point is valid; all we NEED to know is whether it works. And does it? I'd like to know. Charlie will likely never be quite sure. Someone has to figure out how it works to be able to do it competently. No, I can quite competently grill a steak without understanding the physical and chemical changes taking place in the steak when it is heated. And a steak is, I would suggest, a far more complex object than a piece of rusted steel, and the processes involved are also more complex. Not much is likely to go wrong with your strange hobby of dropping rocks on your foot, I would have thought. Now chemical procedures... I'm sure you think they are more complex than the elemental forces of physics or biological systems. We might just have to agree to disagree on that! g I'm with you in fascination with understanding why it works, but that understanding is a want more than a need. Again I disagree. So many things can go wrong with things chemical. So many things waiting to bite you on the ass. DAMHIKT. Yep. Sometimes I overcook a steak, and wonder if a more thorough knowledge of the chemical changes going on in it might have kept me from getting a medium-well steak when I wanted it medium. I, like most woodwrkers, am not a chemist. Are woodworkers prevented from being chemists? Reread the sentence you quoted. Yes, and what point is it trying to make? Charlie is not a chemist, so woodworkers don't need to know any chemistry? No. That he is not a chemist, and that most woodworkers are not chemists, and are probably more interested in whether it works than how it works. Do you disagree? Do you really think that most woodworkers ARE chemists? If they were mine, and I valued them, I would not use salt and vinegar on them. This comes from my understanding of chemistry. Why? What are the bad effects predicted by your understanding of chemistry, and do they prove out in practice? Yep. Salt will enter the fine pits and interstices of the corroded surface and perpetuate future corrosion. Very difficult to clean thoroughly. That's good for part 1 of my question. And I believe I saw in another post that you were going to do an experiment to find out part 2? I'll be interested in hearing your results. There was a guy once who ignored chemistry and shot-blasted his aluminium boat with copper shot. It lasted but a few weeks. Chemistry is VERY important! Absolutely! And this is an excellent example where theory is important to predicting the result of an untried process. -- Alex Make the obvious change in the return address to reply by email. |
|
#61
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy one writes:
Nonsense. What you're saying is that if you don't understand the mechanisms of flight, you don't know that there are aircraft overhead. No, I'm saying that if you don't understand flight, you can't successfully pilot those aircraft. Nonsense. Why on earth not? You do not have to know WHY to know it DOES. Umm, the bit you snipped? Here it is again: "I, like most woodwrkers, am not a chemist." Now what point was that making? That most woodworkers are not chemists. Do you dispute that? If so, on what grounds? So why are you apparently criticising my reasons for not recommending salt and vinegar? Sheesh, we've got one guy who cleans tools left in the rain by the kids with hydrochloric acid! And he claims to be a chemist! I am not criticizing your reasons for not recommending it. I'm not even saying back off. I am saying that the topic has gone on too deeply and too long to be considered a woodworking topic. It is now OT. Because it helps understand the chemistry of corrosion and how to stop it and remove it. If you don't want to understand it, then why do you read it? Do you not understand electrolysis? I do hope you understand it enough to know the dangers involved. Not interested in playing any more of your silly games. And you apparently don't want to find out. That's fine, but why did you join in, if that's the case? You really do have reading comprehension problems, don't you? No, I realised the simiarity after I wrote it. I decided not to pander to your sensibilities by changing it. Marvelous. Or so you think. What sensibilities, by the way? No. Forget it. I forgot to drop this thing in with subject filters last time through. It has now developed it's own silliness, over and above the original unnecessary complexity. Enjoy your continued messing about. Charlie Self "Bore, n.: A person who talks when you wish him to listen." Ambrose Bierce, The Devil's Dictionary |
|
#62
|
|||
|
|||
|
Salt and vinegar for rust removal
|
|
#63
|
|||
|
|||
|
Salt and vinegar for rust removal
"Larry Blanchard" wrote in message
... Why does it work? I don't really care. I find it interesting, but my background is in chemical engineering. -- Where ARE those Iraqi WMDs? Looks like at least some of them are in Iraq. Better change your sig line soon! dwhite |
|
#64
|
|||
|
|||
|
Salt and vinegar for rust removal
On Mon, 17 May 2004 15:33:17 GMT, alexy
posted: Sandy wrote: Disagree. One can observe a cause and effect repeatedly and draw valid conclusions without understanding the mechanism. Disagree. If you don't understand the mechanism, or the rationale, you are very likely to cock it up when things don't go exactly as expected. Especially with complex procedures. LOL! Do you really think that the inorganic chemistry involved in the derusting process is more complex than the operation of the gravitational force and the organic chemistry and electrical processes involved in the sensing, transmittal, and interpretation of the pain signal? Nope, and I don't think I said it was. What I said was the steps involved and decisions needed to implement the procedures are more complex in the derusting example. Dropping a rock on your foot is rather simple, but derusting an object requires many step decisions and step understandings. Understanding theory does help immensely, when deviating from experience, but empirical evidence can be adequate for some instances, such as derusting some particular steel. Which particular steel? How do you tell what kind of steel? So many decisions With the rock example, you don't even have to decide what kind of rock, or which foot to drop it on Where I see theoretical knowledge of the mechanism helping is knowing how it might work on a different alloy, how different solutions might work if the known one is not available, predicting long-term effects if evidence is not available, etc. Exactly, so the bottom line is, are you siding with my desire to thrash out the chemistry involved so we can make rational process decisions, or do you side with Charlie in objecting to the presence of this discussion here because he does not want to understand anything other than a simple recipe that allows for no rational deviation? Folks knew that dropping a stone on their foot would hurt long before Newton and an understanding of the nervous system (and do we yet fully understand the mechanism of gravity, or just have more sophisticated observations about it?) Charlie's point is valid; all we NEED to know is whether it works. And does it? I'd like to know. So would I. That's why I asked the question, and enjoy reading and absorbing the various learned responses I have gotten. Charlie objects to this. God knows why he hasn't got the willpower or tolerance to ignore what does not interest him, but feels the need to stick his nose in and have a whinge. Charlie will likely never be quite sure. Someone has to figure out how it works to be able to do it competently. No, I can quite competently grill a steak without understanding the physical and chemical changes taking place in the steak when it is heated. And if your steak turns out tough, or not to the liking of some consumers? I'm very interested in the biology of steak vis-a-vis the cooking process. Our scientific/agricultural institutions are too, and are studying the subject intensively. And a steak is, I would suggest, a far more complex object than a piece of rusted steel, and the processes involved are also more complex. Not really, depends how deep you go into it. The variation in treating a rusted article are far more diverse than the heating of a steak, but even there, as I explained above there is much process choice even with this simple (apparently) heating process. I've cooked steak according to the "recipe" I knew, only to have it turn out tough sometimes and perfect at other times. I really need to research why this is. Not much is likely to go wrong with your strange hobby of dropping rocks on your foot, I would have thought. Now chemical procedures... I'm sure you think they are more complex than the elemental forces of physics or biological systems. We might just have to agree to disagree on that! g We are talking about two things. The complexity of the phenomenon, and the complexity of the process that a human must undertake. Dropping a rock on your foot is a simple process, whereas derusting a rusty article is a complex process with many decisions to make. Both have underlying phenomena that are equally complex, I would argue. It's the decisions involved in the required steps of the processes that differentiate these two. I'm with you in fascination with understanding why it works, but that understanding is a want more than a need. Again I disagree. So many things can go wrong with things chemical. So many things waiting to bite you on the ass. DAMHIKT. Yep. Sometimes I overcook a steak, and wonder if a more thorough knowledge of the chemical changes going on in it might have kept me from getting a medium-well steak when I wanted it medium. But as I said above, there is apparently much more to cooking steaks. Starting from choosing the piece of meat from the butcher's display case, apparently. I would like to learn more, and listen with interest when I hear the CSIRO discussing their latest research. I, like most woodwrkers, am not a chemist. Are woodworkers prevented from being chemists? Reread the sentence you quoted. Yes, and what point is it trying to make? Charlie is not a chemist, so woodworkers don't need to know any chemistry? No. That he is not a chemist, and that most woodworkers are not chemists, and are probably more interested in whether it works than how it works. Do you disagree? Yep. Close, but not my reading. His context was a complaint that this discussion was irrelevant to this forum, and because he was not a chemist, and couldn't follow it, it should not be discussed here. Do you really think that most woodworkers ARE chemists? Of course not, and that was not the point that Charlie conveyed to me. He was complaining about the presence of the discussion, remember. If they were mine, and I valued them, I would not use salt and vinegar on them. This comes from my understanding of chemistry. Why? What are the bad effects predicted by your understanding of chemistry, and do they prove out in practice? Yep. Salt will enter the fine pits and interstices of the corroded surface and perpetuate future corrosion. Very difficult to clean thoroughly. That's good for part 1 of my question. And I believe I saw in another post that you were going to do an experiment to find out part 2? I'll be interested in hearing your results. I did not mention an experiment regarding this. I have read much on salt inclusions in rust pits, and the resident expert here mentioned such in a girder for a bridge. I would not like to put all my weight behind a rusty spanner that had been soaking in salt in a previous life. There was a guy once who ignored chemistry and shot-blasted his aluminium boat with copper shot. It lasted but a few weeks. Chemistry is VERY important! Absolutely! And this is an excellent example where theory is important to predicting the result of an untried process. Exactly my point. That's why I'm interested, and like you, think it is on topic and worthwhile. I'm rather ****ed off at Charlie for butting in with his selfish objections, and then ****ing off, so to speak. |
|
#66
|
|||
|
|||
|
Salt and vinegar for rust removal
On Mon, 17 May 2004 13:44:10 -0700, Larry Blanchard
posted: In article , says... 2. You have to admit that the NaCl is greatly accelerating the reaction rate. And that's the whole point. It does make a difference - I know, I've tried it both ways. Why does it work? I don't really care. Interesting. And do you expect everyone here to have this lack of interest, like Charlie does? I, for one, care why it is reported to work. You appear not to have considered the downsides of soaking rusted ferrous metal in salt solution? Museums have a hell of a job removing salt from ferrous artifacts found in the sea. |
|
#67
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy wrote...
Dropping a rock on your foot is a simple process, whereas derusting a rusty article is a complex process with many decisions to make. Analogies aside, de-rusting a rusty article is not really a very complex process, nor are there "many" decisions to make, at least not in my understanding of "complex" and "many." Hyperbole, perhaps? Yep. Close, but not my reading. His context was a complaint that this discussion was irrelevant to this forum, and because he was not a chemist, and couldn't follow it, it should not be discussed here. You must have misread, then. Alexy nailed it: "That he is not a chemist, and that most woodworkers are not chemists, and are probably more interested in whether it works than how it works." Additionally, Charlie's suggestion was that the discussion had drifted far enough afield to warrant an "OT" in the subject line, not that it shouldn't be discussed. Your "reading" goes a good bit beyond hyperbole; it teeters precipitously toward mischaracterization. Jim |
|
#68
|
|||
|
|||
|
Salt and vinegar for rust removal
On Tue, 18 May 2004 06:30:01 GMT, Jim Wilson
posted: Sandy wrote... Dropping a rock on your foot is a simple process, whereas derusting a rusty article is a complex process with many decisions to make. Analogies aside, de-rusting a rusty article is not really a very complex process, nor are there "many" decisions to make, at least not in my understanding of "complex" and "many." Hyperbole, perhaps? Nope, comparative. Cf dropping a rock on your foot For the derusting, you must decide what vinegar to use, how long to soak, how much salt, what is that black sludge in the bottom, what sort of steel is it, how much to rinse afterwards, what to apply afterwards, and do you dry it, and how? And those are just a few decisions/questions that occur off the top of my head. I have at the moment on my kitchen sink two tumblers with half an inch of vinegar in each and excess salt in one of them. I have placed several very rusty nails in both tumblers. They have been there for five hours so far. Nothing much is happening, except for a very pale yellowish tinge to the solution. The non-salted one seems a little darker yellow than the salted one, but this could be an optical illusion from the white salt sitting on the bottom. I will leave them there until the nails seem to be clean where treated, and then rinse in tap water, and place out in the weather again for however long. See what the subsequent corrosion is on the cleaned areas. I do hope I get some cleaned areas to compare My conclusion so far is that using vinegar to clean off rust is a waste of bloody time To derust some historic old very rusted horseshoes years ago, I consulted the conservation technicians at the local museum. The technical discussion was fascinating, and I learned a lot from it. But you had to have a basis in chemistry. Yep. Close, but not my reading. His context was a complaint that this discussion was irrelevant to this forum, and because he was not a chemist, and couldn't follow it, it should not be discussed here. You must have misread, then. Alexy nailed it: "That he is not a chemist, and that most woodworkers are not chemists, and are probably more interested in whether it works than how it works." In the context of whining that our discussion was OT for this forum. Otherwise, what was the aim of his message? Additionally, Charlie's suggestion was that the discussion had drifted far enough afield to warrant an "OT" in the subject line, not that it shouldn't be discussed. Nope, strictly speaking, OT subjects should not be discussed on newsgroups. Of course they are, but as at least two of us thought our discussion was on topic, I suggest Charlie was out of line. Look at the subject header. Your "reading" goes a good bit beyond hyperbole; it teeters precipitously toward mischaracterization. So why did he say that he was not a chemist and most woodworkers were not chemists? Just idle chit chat? Sorry, I thought he was trying to make a point in his context of complaining about our discussion. The point I received was that because he didn't understand the discussion, it was irrelevant on this forum. Otherwise, you are saying that Charlie makes silly comments, out of context, and is therefore perhaps a bit loopy? I thought he was just a busybody wanting to have a moan about something. Could he not just have ignored what did not interest HIM? What really was the point of Charlie's interjection? It contributed nothing except to complain about what *his* message was even more guilty of. If he was not interested, he should have just ignored it. |
|
#69
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy wrote...
Jim Wilson posted: Hyperbole, perhaps? Nope, comparative. Cf dropping a rock on your foot Ok, perhaps more complex than dropping a rock on your foot, but that doesn't say a whole lot, does it? (G) My conclusion so far is that using vinegar to clean off rust is a waste of bloody time It certainly is if you watch it. (G) In the context of whining that our discussion was OT for this forum. Otherwise, what was the aim of his message? That wasn't the context. He started by disagreeing with your assertion that "What we need explaining is why the presence of sodium chloride in the vinegar is advantageous." He noted that "we" non-chemist woodworkers do not need that explained at all. We need only know whether it works, not why. Indeed, even a correct, lucid, and perfectly presented explanation would be of limited utility to the majority, although it might well be interesting to many of us. An inconclusive, jargon-filled technical debate would have to have considerably less utility, wouldn't you agree? Only afterward did he observe that the thread had wandered into OT territory, and even then he did not suggest aborting the thread, but rather that the subject line should have been altered. Don't get me wrong -- personally, I am quite interested in the discussion, and have been following the thread closely, but obviously I do have a penchant for useless academic debate :-). I interjected because I felt your take on Charlie's post was wrong, and that the points he was really trying to make were valid, to wit: 1) most readers of this NG neither need nor want to understand this stuff, and 2) the thread has drifted off topic for this NG. I still want to hear it. Jim |
|
#70
|
|||
|
|||
|
OT: Salt and vinegar for rust removal
There. Does that settle it?
dwhite "Jim Wilson" wrote in message .net... Sandy wrote... Jim Wilson posted: Hyperbole, perhaps? Nope, comparative. Cf dropping a rock on your foot Ok, perhaps more complex than dropping a rock on your foot, but that doesn't say a whole lot, does it? (G) My conclusion so far is that using vinegar to clean off rust is a waste of bloody time It certainly is if you watch it. (G) In the context of whining that our discussion was OT for this forum. Otherwise, what was the aim of his message? That wasn't the context. He started by disagreeing with your assertion that "What we need explaining is why the presence of sodium chloride in the vinegar is advantageous." He noted that "we" non-chemist woodworkers do not need that explained at all. We need only know whether it works, not why. Indeed, even a correct, lucid, and perfectly presented explanation would be of limited utility to the majority, although it might well be interesting to many of us. An inconclusive, jargon-filled technical debate would have to have considerably less utility, wouldn't you agree? Only afterward did he observe that the thread had wandered into OT territory, and even then he did not suggest aborting the thread, but rather that the subject line should have been altered. Don't get me wrong -- personally, I am quite interested in the discussion, and have been following the thread closely, but obviously I do have a penchant for useless academic debate :-). I interjected because I felt your take on Charlie's post was wrong, and that the points he was really trying to make were valid, to wit: 1) most readers of this NG neither need nor want to understand this stuff, and 2) the thread has drifted off topic for this NG. I still want to hear it. Jim |
|
#71
|
|||
|
|||
|
OT: Salt and vinegar for rust removal
Dan White wrote...
There. Does that settle it? LOL! I figured everyone else had already bailed on the thread! (G) Jim |
|
#72
|
|||
|
|||
|
OT: Salt and vinegar for rust removal
"Jim Wilson" wrote in message
k.net... Dan White wrote... There. Does that settle it? LOL! I figured everyone else had already bailed on the thread! (G) Jim Hell no! I've got my own two samples of rusted iron soaking in Palmolive right now. Where's Madge? Actually I am doing my own salt/no salt test and will report here when it is done. dwhite |
|
#73
|
|||
|
|||
|
Salt and vinegar for rust removal
On Tue, 18 May 2004 15:49:00 GMT, Jim Wilson
posted: Sandy wrote... Jim Wilson posted: Hyperbole, perhaps? Nope, comparative. Cf dropping a rock on your foot Ok, perhaps more complex than dropping a rock on your foot, but that doesn't say a whole lot, does it? (G) No, but then I didn't introduce that comparison My conclusion so far is that using vinegar to clean off rust is a waste of bloody time It certainly is if you watch it. (G) Well it's approaching 24 hours and I've just had 9 hours' sleep and the situation has not changed. Very pale yellow in the non-salt vinegar, and if you have a really good imagination, a very,very pale yellow in the salt vinegar. The nails have suffered NO observable change. In the context of whining that our discussion was OT for this forum. Otherwise, what was the aim of his message? That wasn't the context. He started by disagreeing with your assertion that "What we need explaining is why the presence of sodium chloride in the vinegar is advantageous." He noted that "we" non-chemist woodworkers do not need that explained at all. We need only know whether it works, not why. So why did he go on to assert that our discussion was irrelevant? Your explanation does not account for that. Seems he should have kept his mouth shut if he was no longer interested. There are many threads that I'm not interested in, and I just ignore them. When our discussion/experiments are done, we should have a clear conclusion as to whether it is at all efficaceous. With or without salt. WTF is off topic about that? Sheeesh! Indeed, even a correct, lucid, and perfectly presented explanation would be of limited utility to the majority, although it might well be interesting to many of us. So it is decidedly NOT off topic as Charlie was asserting? Look at the subject line. Many woodworkers are interested in deructing old valuable tools, or so I've read here. An inconclusive, jargon-filled technical debate would have to have considerably less utility, wouldn't you agree? No jargon in our discussion, sorry. Yes a few technical terms that are easy to find out about if you don't already know, and all technical subjects must have these terms and must deal with technicalities to understand them. Understanding brings ability to adjust for different circumstances, or so I find. Someone suggested that salt was excellent in vinegar solution for removing rust. I queried this as my basic understanding of chemistry didn't tell me why this would be so. I've now done an experiment that shows that vinegar with and without salt is virtually useless in derusting rusty ferrous metal. I always followed this in practice (never having had any successs with vinegar in the past few times I've tried it.) Adding salt makes no difference if you are generous. In my experiment, it was less effective than just the plain vinegar. Only afterward did he observe that the thread had wandered into OT territory, and even then he did not suggest aborting the thread, but rather that the subject line should have been altered. On what ground? It was NOT Off Topic. More than one of us was interested in it. And it was to do with derusting woodworking tools as per the subject header. And then what was the overall aim of his message? To have a whinge, No? Don't get me wrong -- personally, I am quite interested in the discussion, and have been following the thread closely, but obviously I do have a penchant for useless academic debate :-). Interesting that you think it is useless. I've found through my life, that one of the handiest bits of knowledge I carry around with me, is my basic chemistry. It helps in just about everything I do. I interjected because I felt your take on Charlie's post was wrong, and that the points he was really trying to make were valid, to wit: 1) most readers of this NG neither need nor want to understand this stuff, And his point? Can't they just ignore it? I take it as read, that not every reader here is interested in every topic. I ignore most of them. I don't interject that the topic is OT. and 2) the thread has drifted off topic for this NG. Which it patently hasn't. The subject header says it all. I still want to hear it. Then, by definition, it is ON topic. I read Charlies message as someone being selfish and wanting no discussions that either he couldn't follow, or that he was not interested in. He should have ignored it, like most other rational posters obviously did. Does he often play "NetCop"? |
|
#74
|
|||
|
|||
|
Salt and vinegar for rust removal
On Tue, 18 May 2004 16:07:14 GMT, "Dan White"
posted: There. Does that settle it? Settle what? That salt and vinegar are useless for derusting rusty tools? Pretty much, I would contend, so far. That Charlie was being a whinging busybody by complaining about our discussion? Yep, see my reponse to Jim. "Jim Wilson" wrote in message k.net... Sandy wrote... Jim Wilson posted: Hyperbole, perhaps? Nope, comparative. Cf dropping a rock on your foot Ok, perhaps more complex than dropping a rock on your foot, but that doesn't say a whole lot, does it? (G) My conclusion so far is that using vinegar to clean off rust is a waste of bloody time It certainly is if you watch it. (G) In the context of whining that our discussion was OT for this forum. Otherwise, what was the aim of his message? That wasn't the context. He started by disagreeing with your assertion that "What we need explaining is why the presence of sodium chloride in the vinegar is advantageous." He noted that "we" non-chemist woodworkers do not need that explained at all. We need only know whether it works, not why. Indeed, even a correct, lucid, and perfectly presented explanation would be of limited utility to the majority, although it might well be interesting to many of us. An inconclusive, jargon-filled technical debate would have to have considerably less utility, wouldn't you agree? Only afterward did he observe that the thread had wandered into OT territory, and even then he did not suggest aborting the thread, but rather that the subject line should have been altered. Don't get me wrong -- personally, I am quite interested in the discussion, and have been following the thread closely, but obviously I do have a penchant for useless academic debate :-). I interjected because I felt your take on Charlie's post was wrong, and that the points he was really trying to make were valid, to wit: 1) most readers of this NG neither need nor want to understand this stuff, and 2) the thread has drifted off topic for this NG. I still want to hear it. Jim |
|
#75
|
|||
|
|||
|
Salt and vinegar for rust removal
On Tue, 18 May 2004 22:19:36 GMT, Jim Wilson
posted: Dan White wrote... There. Does that settle it? LOL! I figured everyone else had already bailed on the thread! (G) So I shouldn't have bothered to show the results of my experiment? No-one else is interested? It really staggers me that folks are happy to continue with a useless, but potentially harmful derusting technique just because the rationale gets a little hard. OK, I'll keep my mouth shut in future |
|
#76
|
|||
|
|||
|
Salt and vinegar for rust removal
Sandy wrote...
mucho snippage Jim Wilson posted: ... Don't get me wrong -- personally, I am quite interested in the discussion, and have been following the thread closely, but obviously I do have a penchant for useless academic debate :-). Interesting that you think it is useless. I've found through my life, that one of the handiest bits of knowledge I carry around with me, is my basic chemistry. It helps in just about everything I do. See the smiley? I was jesting about the discussion between you and me. (G) As regards the rest of your post, you've made your points and I've made mine, so I guess we're done. Cheers! Jim |
|
#77
|
|||
|
|||
|
Salt and vinegar for rust removal
"Sandy" wrote in message news  On Tue, 18 May 2004 16:07:14 GMT, "Dan White" posted: There. Does that settle it? Settle what? Hey, lighten up! It was just a joke. I'm on your side, anyway. I havesome rusted metal soaking for about 36 hours now. I'll stop it Wed afternoon and see what I get. I'll let you know, fwiw. dwhite That salt and vinegar are useless for derusting rusty tools? Pretty much, I would contend, so far. That Charlie was being a whinging busybody by complaining about our discussion? Yep, see my reponse to Jim. "Jim Wilson" wrote in message k.net... Sandy wrote... Jim Wilson posted: Hyperbole, perhaps? Nope, comparative. Cf dropping a rock on your foot Ok, perhaps more complex than dropping a rock on your foot, but that doesn't say a whole lot, does it? (G) My conclusion so far is that using vinegar to clean off rust is a waste of bloody time It certainly is if you watch it. (G) In the context of whining that our discussion was OT for this forum. Otherwise, what was the aim of his message? That wasn't the context. He started by disagreeing with your assertion that "What we need explaining is why the presence of sodium chloride in the vinegar is advantageous." He noted that "we" non-chemist woodworkers do not need that explained at all. We need only know whether it works, not why. Indeed, even a correct, lucid, and perfectly presented explanation would be of limited utility to the majority, although it might well be interesting to many of us. An inconclusive, jargon-filled technical debate would have to have considerably less utility, wouldn't you agree? Only afterward did he observe that the thread had wandered into OT territory, and even then he did not suggest aborting the thread, but rather that the subject line should have been altered. Don't get me wrong -- personally, I am quite interested in the discussion, and have been following the thread closely, but obviously I do have a penchant for useless academic debate :-). I interjected because I felt your take on Charlie's post was wrong, and that the points he was really trying to make were valid, to wit: 1) most readers of this NG neither need nor want to understand this stuff, and 2) the thread has drifted off topic for this NG. I still want to hear it. Jim |
|
#78
|
|||
|
|||
|
Salt and vinegar for rust removal
On Wed, 19 May 2004 05:22:12 GMT, "Dan White"
posted: "Sandy" wrote in message news On Tue, 18 May 2004 16:07:14 GMT, "Dan White" posted: There. Does that settle it? Settle what? Hey, lighten up! Sorry, that sounded much more serious than intended It was just a joke. I'm on your side, anyway. I have some rusted metal soaking for about 36 hours now. I'll stop it Wed afternoon and see what I get. I'll let you know, fwiw. I'm now getting a bit of effervescence in mine. Carbonates dissolving, I guess. That's a more promising sign, but 28 hours shows very little cleaning. Not long ago, I stuck a very rusted hose clamp (hydraulically applied) in vinegar in the hope that it would fall apart. What it did do was to make the non-rusted chromed areas nice and shiny. As there was still a lot of metal left, and not all rust as it originally seemed, it required 3000 rpm of an 8" alumina wheel My impression so far is that the salt impedes the derusting process. I have read in places that salt is added to vinegar as a mild abrasive when rubbing a rusted item clean. This is a very different process than the one claimed in this thread. That salt and vinegar are useless for derusting rusty tools? Pretty much, I would contend, so far. That Charlie was being a whinging busybody by complaining about our discussion? Yep, see my reponse to Jim. "Jim Wilson" wrote in message k.net... Sandy wrote... Jim Wilson posted: Hyperbole, perhaps? Nope, comparative. Cf dropping a rock on your foot Ok, perhaps more complex than dropping a rock on your foot, but that doesn't say a whole lot, does it? (G) My conclusion so far is that using vinegar to clean off rust is a waste of bloody time It certainly is if you watch it. (G) In the context of whining that our discussion was OT for this forum. Otherwise, what was the aim of his message? That wasn't the context. He started by disagreeing with your assertion that "What we need explaining is why the presence of sodium chloride in the vinegar is advantageous." He noted that "we" non-chemist woodworkers do not need that explained at all. We need only know whether it works, not why. Indeed, even a correct, lucid, and perfectly presented explanation would be of limited utility to the majority, although it might well be interesting to many of us. An inconclusive, jargon-filled technical debate would have to have considerably less utility, wouldn't you agree? Only afterward did he observe that the thread had wandered into OT territory, and even then he did not suggest aborting the thread, but rather that the subject line should have been altered. Don't get me wrong -- personally, I am quite interested in the discussion, and have been following the thread closely, but obviously I do have a penchant for useless academic debate :-). I interjected because I felt your take on Charlie's post was wrong, and that the points he was really trying to make were valid, to wit: 1) most readers of this NG neither need nor want to understand this stuff, and 2) the thread has drifted off topic for this NG. I still want to hear it. Jim |
|
#79
|
|||
|
|||
|
Salt and vinegar for rust removal
On Wed, 19 May 2004 04:49:52 GMT, Jim Wilson
posted: Sandy wrote... mucho snippage Jim Wilson posted: ... Don't get me wrong -- personally, I am quite interested in the discussion, and have been following the thread closely, but obviously I do have a penchant for useless academic debate :-). Interesting that you think it is useless. I've found through my life, that one of the handiest bits of knowledge I carry around with me, is my basic chemistry. It helps in just about everything I do. See the smiley? I was jesting about the discussion between you and me. (G) Of course, and I was adding my 2 cents to the conversation. As regards the rest of your post, you've made your points and I've made mine, so I guess we're done. Until we post our results, perhaps? Cheers! And to you too. |
|
#80
|
|||
|
|||
|
Test Results was Salt and vinegar for rust removal
First of all let me say that my interest in this thread, started by Sandy,
was caused by my own questioning of why salt helped clean copper pots with vinegar. Months ago I poured vinegar on a copper pot and it did nothing. Then I sprinkled salt on, and the oxides just wiped away. I figure whatever mechanism was working there is probably not that different from what happens with iron. So on with my not-so-scientifically-controlled test: I didn't have any rusted nails, but I did find two old 1.25 lb free weights. These are 4" in diameter with a 1" hole for the barbell to go through. The annular region between this hole and the outer edge of the weight was recessed and could hold maybe a tablespoon worth of liquid, possibly more. The annular region was embossed with the manufacturer's name and the weight. Each weight was rusted moderately and had about the same amount of rust. This means that there is more rust than you could casually remove, but not so much that the weight had deep pits. I poured vinegar into both, and then added an excess of salt to one of them. Within hours, both were effervescing slightly. (They had bubbles collecting on the surface). Note that this was done in contact with air, and with plenty of surface area. After 48 hours I poured the liquid out of each into test tube like containers. What I observe is that the vinegar/salt sample was a light yellowish/orange color, and contained a fair amount of black flecks and little chunks, in addition to some very small black particles. On the other hand, the vinegar/no salt solution was a deep red color, very different from the vinegar/salt sample. It had no flecks or chunks of black material, but did have a fair amount of very fine, small black particles. In both cases, black material built up on the edges of the liquid, and also on some of the submerged surfaces. I cleaned the weights by hand and observed that the rust was gone from both, but the vinegar/salt weight looked SLIGHTLY cleaner. I then used a brass brush to clean them up further. After drying them out, it appears that the vinegar/salt weight is a little brighter looking. The vinegar only weight looks darker, as if there is dark material caught up in the fine pits and crevices of the weight. Overall I'd say that there is a definite difference between the two as one liquid was light yellow or orange, and the other was deep red. The vinegar/salt weight also looked a little cleaner, but it is a very slight difference. It could be that these old weights just looked a little different from the start. What caused the red color in one and not the other? Is the iron chloride complex colorless, while FeCl3 is red? Sorry for being long-winded. Hope this spurs some ideas. dwhite PS. I might add clean water to each next to see if there is any difference in corrosion rate as postulated by Sandy. "Sandy" wrote in message ... On Wed, 19 May 2004 05:22:12 GMT, "Dan White" posted: "Sandy" wrote in message news On Tue, 18 May 2004 16:07:14 GMT, "Dan White" posted: There. Does that settle it? Settle what? Hey, lighten up! Sorry, that sounded much more serious than intended It was just a joke. I'm on your side, anyway. I have some rusted metal soaking for about 36 hours now. I'll stop it Wed afternoon and see what I get. I'll let you know, fwiw. I'm now getting a bit of effervescence in mine. Carbonates dissolving, I guess. That's a more promising sign, but 28 hours shows very little cleaning. Not long ago, I stuck a very rusted hose clamp (hydraulically applied) in vinegar in the hope that it would fall apart. What it did do was to make the non-rusted chromed areas nice and shiny. As there was still a lot of metal left, and not all rust as it originally seemed, it required 3000 rpm of an 8" alumina wheel My impression so far is that the salt impedes the derusting process. I have read in places that salt is added to vinegar as a mild abrasive when rubbing a rusted item clean. This is a very different process than the one claimed in this thread. That salt and vinegar are useless for derusting rusty tools? Pretty much, I would contend, so far. That Charlie was being a whinging busybody by complaining about our discussion? Yep, see my reponse to Jim. "Jim Wilson" wrote in message k.net... Sandy wrote... Jim Wilson posted: Hyperbole, perhaps? Nope, comparative. Cf dropping a rock on your foot Ok, perhaps more complex than dropping a rock on your foot, but that doesn't say a whole lot, does it? (G) My conclusion so far is that using vinegar to clean off rust is a waste of bloody time It certainly is if you watch it. (G) In the context of whining that our discussion was OT for this forum. Otherwise, what was the aim of his message? That wasn't the context. He started by disagreeing with your assertion that "What we need explaining is why the presence of sodium chloride in the vinegar is advantageous." He noted that "we" non-chemist woodworkers do not need that explained at all. We need only know whether it works, not why. Indeed, even a correct, lucid, and perfectly presented explanation would be of limited utility to the majority, although it might well be interesting to many of us. An inconclusive, jargon-filled technical debate would have to have considerably less utility, wouldn't you agree? Only afterward did he observe that the thread had wandered into OT territory, and even then he did not suggest aborting the thread, but rather that the subject line should have been altered. Don't get me wrong -- personally, I am quite interested in the discussion, and have been following the thread closely, but obviously I do have a penchant for useless academic debate :-). I interjected because I felt your take on Charlie's post was wrong, and that the points he was really trying to make were valid, to wit: 1) most readers of this NG neither need nor want to understand this stuff, and 2) the thread has drifted off topic for this NG. I still want to hear it. Jim |
| Reply |
| Thread Tools | Search this Thread |
| Display Modes | |
|
|
Similar Threads
|
||||
| Thread | Forum | |||
| Rust removal... | Metalworking | |||
Linear Mode
