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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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Great dollops of that white goo between metal to metal thermally conductive
surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. |
#2
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On 1/19/2011 9:54 AM, N_Cook wrote:
Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Heat sink compound is usually very necessary. One of my pet hates is torx screws with a pin in the center. |
#3
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Lab1 .@... wrote in message
... On 1/19/2011 9:54 AM, N_Cook wrote: Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Heat sink compound is usually very necessary. One of my pet hates is torx screws with a pin in the center. The harware that I always have problems with in the UK , never organised a stock of, is UNF and UNC nuts and bolts for USA kit. And of course,vice versa, repairers in USA never have metric (and lesser extent BA) for UK and Japanese kit |
#4
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![]() "N_Cook" wrote in message ... Lab1 .@... wrote in message ... On 1/19/2011 9:54 AM, N_Cook wrote: Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Heat sink compound is usually very necessary. One of my pet hates is torx screws with a pin in the center. The harware that I always have problems with in the UK , never organised a stock of, is UNF and UNC nuts and bolts for USA kit. And of course,vice versa, repairers in USA never have metric (and lesser extent BA) for UK and Japanese kit I once got in a lot of trouble with my boss when I was young and worked for a U.S. based company. At that time, I didn't understand that there was a big difference between British 'tongue-in-cheek' humour, and the much more direct U.S. type. I was talking on the phone to one of the designers of a piece of equipment that we sold here in the UK, and asked the guy if he could arrange to send me some screws for the cabinet, as they were a thread that we didn't readily get over here. He asked if I knew exactly what size they were so I replied, quick as a flash, thinking that I was being funny, "I guess that they are round about 3/16ths APF." "What's APF ?" the guy asked. "American **** Fit", said I ... Stony silence on the phone. Half an hour later, I was summoned to the boss's office. Apparently, the guy had been really offended by this, thinking that it was a slur on what he considered to be good American engineering, and had called my boss to complain about me. Just goes to show how easily offence can be caused between nations, even when they speak what's basically the same language ... :-) Arfa |
#5
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On 1/19/2011 1:00 PM, Arfa Daily wrote:
I once got in a lot of trouble with my boss when I was young and worked for a U.S. based company. At that time, I didn't understand that there was a big difference between British 'tongue-in-cheek' humour, and the much more direct U.S. type. I was talking on the phone to one of the designers of a piece of equipment that we sold here in the UK, and asked the guy if he could arrange to send me some screws for the cabinet, as they were a thread that we didn't readily get over here. He asked if I knew exactly what size they were so I replied, quick as a flash, thinking that I was being funny, "I guess that they are round about 3/16ths APF." "What's APF ?" the guy asked. "American **** Fit", said I ... Stony silence on the phone. Half an hour later, I was summoned to the boss's office. Apparently, the guy had been really offended by this, thinking that it was a slur on what he considered to be good American engineering, and had called my boss to complain about me. Just goes to show how easily offence can be caused between nations, even when they speak what's basically the same language ... :-) While on vacation in the Dominican Republic we ran into a really nice group from the UK who were there for a wedding. We would hang out and talk with them down at the in-pool bar almost every evening. I never quite got used to them asking me to bum a fag. I'm from the US and I smoke cigarettes, not fags. -- -Scott |
#6
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Lab1 wrote:
I'm from the US and I smoke cigarettes, not fags. Michael Terrell's from the US and he smokes fags, not cigarettes. |
#7
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I once got in a lot of trouble with my boss when I was young and worked
for a U.S. based company. At that time, I didn't understand that there was a big difference between British 'tongue-in-cheek' humour, and the much more direct U.S. type. I was talking on the phone to one of the designers of a piece of equipment that we sold here in the UK, and asked the guy if he could arrange to send me some screws for the cabinet, as they were a thread that we didn't readily get over here. He asked if I knew exactly what size they were so I replied, quick as a flash, thinking that I was being funny, "I guess that they are round about 3/16ths APF." "What's APF ?" the guy asked. "American **** Fit", said I ... Stony silence on the phone. Half an hour later, I was summoned to the boss's office. Apparently, the guy had been really offended by this, thinking that it was a slur on what he considered to be good American engineering, and had called my boss to complain about me. Just goes to show how easily offence can be caused between nations, even when they speak what's basically the same language ... :-) It's hard /not/ to interpret such a description as an intentional insult. I can't imagine what it actually means -- in any innocuous sense, anyway. |
#8
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![]() "William Sommerwerck" wrote in message ... I once got in a lot of trouble with my boss when I was young and worked for a U.S. based company. At that time, I didn't understand that there was a big difference between British 'tongue-in-cheek' humour, and the much more direct U.S. type. I was talking on the phone to one of the designers of a piece of equipment that we sold here in the UK, and asked the guy if he could arrange to send me some screws for the cabinet, as they were a thread that we didn't readily get over here. He asked if I knew exactly what size they were so I replied, quick as a flash, thinking that I was being funny, "I guess that they are round about 3/16ths APF." "What's APF ?" the guy asked. "American **** Fit", said I ... Stony silence on the phone. Half an hour later, I was summoned to the boss's office. Apparently, the guy had been really offended by this, thinking that it was a slur on what he considered to be good American engineering, and had called my boss to complain about me. Just goes to show how easily offence can be caused between nations, even when they speak what's basically the same language ... :-) It's hard /not/ to interpret such a description as an intentional insult. I can't imagine what it actually means -- in any innocuous sense, anyway. There ya go then ! Anyone from the UK would see it as a quick-fire throw-away line, and would laugh at it. It's sort of intended to be 'barbed', but not in a malicious way. It's a very hard to describe form of humour that is quite prevalent over here. Arfa |
#9
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On Wed, 19 Jan 2011 18:00:17 -0000, "Arfa Daily"
wrote: "N_Cook" wrote in message ... Lab1 .@... wrote in message ... On 1/19/2011 9:54 AM, N_Cook wrote: Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Heat sink compound is usually very necessary. One of my pet hates is torx screws with a pin in the center. The harware that I always have problems with in the UK , never organised a stock of, is UNF and UNC nuts and bolts for USA kit. And of course,vice versa, repairers in USA never have metric (and lesser extent BA) for UK and Japanese kit I once got in a lot of trouble with my boss when I was young and worked for a U.S. based company. At that time, I didn't understand that there was a big difference between British 'tongue-in-cheek' humour, and the much more direct U.S. type. I was talking on the phone to one of the designers of a piece of equipment that we sold here in the UK, and asked the guy if he could arrange to send me some screws for the cabinet, as they were a thread that we didn't readily get over here. He asked if I knew exactly what size they were so I replied, quick as a flash, thinking that I was being funny, "I guess that they are round about 3/16ths APF." "What's APF ?" the guy asked. "American **** Fit", said I ... Stony silence on the phone. Half an hour later, I was summoned to the boss's office. Apparently, the guy had been really offended by this, thinking that it was a slur on what he considered to be good American engineering, and had called my boss to complain about me. Just goes to show how easily offence can be caused between nations, even when they speak what's basically the same language ... :-) Arfa I think it matters in what part of the U.S. this person resided. I'm originally from the North East and humor that would be considered mild there is considered a great affront to some people in the South. However, racist remarks, that I find offensive, don't seem to bother their delicate constitutions. Chuck |
#10
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![]() "Chuck" wrote in message ... On Wed, 19 Jan 2011 18:00:17 -0000, "Arfa Daily" wrote: "N_Cook" wrote in message ... Lab1 .@... wrote in message ... On 1/19/2011 9:54 AM, N_Cook wrote: Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Heat sink compound is usually very necessary. One of my pet hates is torx screws with a pin in the center. The harware that I always have problems with in the UK , never organised a stock of, is UNF and UNC nuts and bolts for USA kit. And of course,vice versa, repairers in USA never have metric (and lesser extent BA) for UK and Japanese kit I once got in a lot of trouble with my boss when I was young and worked for a U.S. based company. At that time, I didn't understand that there was a big difference between British 'tongue-in-cheek' humour, and the much more direct U.S. type. I was talking on the phone to one of the designers of a piece of equipment that we sold here in the UK, and asked the guy if he could arrange to send me some screws for the cabinet, as they were a thread that we didn't readily get over here. He asked if I knew exactly what size they were so I replied, quick as a flash, thinking that I was being funny, "I guess that they are round about 3/16ths APF." "What's APF ?" the guy asked. "American **** Fit", said I ... Stony silence on the phone. Half an hour later, I was summoned to the boss's office. Apparently, the guy had been really offended by this, thinking that it was a slur on what he considered to be good American engineering, and had called my boss to complain about me. Just goes to show how easily offence can be caused between nations, even when they speak what's basically the same language ... :-) Arfa I think it matters in what part of the U.S. this person resided. I'm originally from the North East and humor that would be considered mild there is considered a great affront to some people in the South. However, racist remarks, that I find offensive, don't seem to bother their delicate constitutions. Chuck He was in sunny Caffy-lornia ... Costa Mesa in Orange County, a few miles down the Interstate from LA Arfa |
#11
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On Wed, 19 Jan 2011 16:39:09 -0000, N_Cook wrote:
The harware that I always have problems with in the UK , never organised a stock of, is UNF and UNC nuts and bolts for USA kit. And of course,vice versa, repairers in USA never have metric (and lesser extent BA) for UK and Japanese kit Here in the colonies, whenever I have a piece of unrepairable Made in Japan, Made in Tiawan, Made in Korea kit, or Made in China POS that is going to the landfill, I use some of my 'mental health' time to disassemble the thing and toss all the screws, nuts, washers, shaft nuts and washers, etc. into a bank of 'metric' jelly jars. WFM Jonesy -- Marvin L Jones | jonz | W3DHJ | linux 38.24N 104.55W | @ config.com | Jonesy | OS/2 * Killfiling google & XXXXbanter.com: jonz.net/ng.htm |
#12
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In article ,
N_Cook wrote: The harware that I always have problems with in the UK , never organised a stock of, is UNF and UNC nuts and bolts for USA kit. Have a look in a classic car mag. A few companies sell selections of UNF and UNC nuts and bolts. Or sell individually. -- *Proofread carefully to see if you any words out or mispeld something * Dave Plowman London SW To e-mail, change noise into sound. |
#13
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Dave Plowman (News) wrote in message
... In article , N_Cook wrote: The harware that I always have problems with in the UK , never organised a stock of, is UNF and UNC nuts and bolts for USA kit. Have a look in a classic car mag. A few companies sell selections of UNF and UNC nuts and bolts. Or sell individually. -- *Proofread carefully to see if you any words out or mispeld something * Dave Plowman London SW To e-mail, change noise into sound. This is a useful resource near me, stainless steel only and tend to be larger sizes. One man band , now internet only but no minimum order so worth bookmarking. http://www.a2a4.com/acatalog/ Last time I talked to him, late 2010, he mentioned he was starting a range of "classic car" nuts and bolts , whatever that is, cannot find mention on his site though |
#14
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In article ,
N_Cook wrote: Last time I talked to him, late 2010, he mentioned he was starting a range of "classic car" nuts and bolts , whatever that is, cannot find mention on his site though In the UK, modern cars use metric threads. Ones from about after WW2 to the '80s mainly UNF and UNC. Pre WW2 BSW and BSF. BA was common for electrical stuff. A classic car is really just any which isn't recent and not defined under the strict headings of vintage etc. It isn't restricted to any make - just over 20 years old. Although that age isn't agreed by everyone. -- *Work like you don't need the money. Love like you've never been hurt. Dave Plowman London SW To e-mail, change noise into sound. |
#15
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![]() Lab1 wrote: On 1/19/2011 9:54 AM, N_Cook wrote: Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Heat sink compound is usually very necessary. One of my pet hates is torx screws with a pin in the center. Can't afford $5 for a set of security bits? -- You can't fix stupid. You can't even put a band-aid on it, because it's Teflon coated. |
#16
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On 1/19/2011 2:50 PM, Michael A. Terrell wrote:
Lab1 wrote: On 1/19/2011 9:54 AM, N_Cook wrote: Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Heat sink compound is usually very necessary. One of my pet hates is torx screws with a pin in the center. Can't afford $5 for a set of security bits? Yes, but given the frequency that I run into those I find my punch set and hammer tend to do the trick - security torx to just torx! ![]() -- -Scott |
#17
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![]() Lab1 wrote: On 1/19/2011 2:50 PM, Michael A. Terrell wrote: Lab1 wrote: On 1/19/2011 9:54 AM, N_Cook wrote: Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Heat sink compound is usually very necessary. One of my pet hates is torx screws with a pin in the center. Can't afford $5 for a set of security bits? Yes, but given the frequency that I run into those I find my punch set and hammer tend to do the trick - security torx to just torx! ![]() As long as there is no liability involved. If someone else opens it with a 'just torx' tool and is hurt or killed, you could be sued. I just carry the security tools in my toolbox and and ready for a loot of different hardware. I even keep Posidrive in the same toolbox. -- You can't fix stupid. You can't even put a band-aid on it, because it's Teflon coated. |
#18
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![]() "N_Cook" wrote in message ... Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Me and white heatsink goo have a very bad working relationship. I only have to walk into the workshop when there's something on the bench using it, and all of a sudden, I'm covered in the rotten stuff, without even going near the bench. At least it seems that way ... :-\ Arfa |
#19
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Poodles.
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#20
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![]() William Sommerwerck wrote: Poodles. Puddles. Under Poodles. ;-) -- You can't fix stupid. You can't even put a band-aid on it, because it's Teflon coated. |
#21
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Packing peanuts.
Probe slips. People begging me to work on stuff which I used to turn away, but now have to take in because business is slow. Mark Z. |
#22
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On Thu, 20 Jan 2011 05:29:16 -0600 "Mark Zacharias"
wrote in Message id: om: Packing peanuts. There's a good one. Especially when the humidity is very low, and the peanuts are all broken up in pieces! |
#23
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![]() JW wrote: On Thu, 20 Jan 2011 05:29:16 -0600 "Mark Zacharias" wrote in Message id: om: Packing peanuts. There's a good one. Especially when the humidity is very low, and the peanuts are all broken up in pieces! Low humidity is rarely a problem in Florida. ![]() -- You can't fix stupid. You can't even put a band-aid on it, because it's Teflon coated. |
#24
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![]() "Michael A. Terrell" wrote in message m... JW wrote: On Thu, 20 Jan 2011 05:29:16 -0600 "Mark Zacharias" wrote in Message id: om: Packing peanuts. There's a good one. Especially when the humidity is very low, and the peanuts are all broken up in pieces! Low humidity is rarely a problem in Florida. ![]() -- You can't fix stupid. You can't even put a band-aid on it, because it's Teflon coated. Yeah.. One time I was going to paint something. The can of spray paint said to only use it in 50% or less humidity. I laughed when I read that and thought there must be less than 20 days a year that would have low enough humidity to paint this thing.. |
#25
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![]() "Mark Zacharias" wrote in message eb.com... Packing peanuts. Probe slips. People begging me to work on stuff which I used to turn away, but now have to take in because business is slow. Mark Z. Yep. Amen to that one ... Arfa |
#26
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heat sink goop
cars with both metric and english fasteners bristol spline srews |
#27
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Ron D. wrote in message
... heat sink goop cars with both metric and english fasteners bristol spline srews Could you describe a "bristol spline screw" Google-images no help other than they are used on 30KV rated relays |
#28
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![]() N_Cook wrote: Ron D. wrote in message ... heat sink goop cars with both metric and english fasteners bristol spline srews Could you describe a "bristol spline screw" Google-images no help other than they are used on 30KV rated relays Bristol was used in electronic equipment build by the US during W.W.-II. http://en.wikipedia.org/wiki/Wrench, almost half way down the page. http://www.bristolwrench.com/ still makes them. http://www.bristolwrench.com/spline.pdf They are availible from a lot of industrial tool dealers. A lot of people called them 'Spline Wrenches' instead of Bristol Wrenches. -- You can't fix stupid. You can't even put a band-aid on it, because it's Teflon coated. |
#29
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On Wed, 19 Jan 2011 14:54:35 +0000, N_Cook wrote:
Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. I always wipe away with paper etc on first parting but always some gets on my clothing - I've not worn white lab coats for many a year. Overuse of that stuff is worse for thermal conductivity than none at all. I've clean up gobs of it since they started using it decades ago. -- Live Fast, Die Young and Leave a Pretty Corpse |
#30
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On 1/19/2011 2:25 PM, Meat Plow wrote:
Great dollops of that white goo between metal to metal thermally conductive surfaces. Overuse of that stuff is worse for thermal conductivity than none at all. I've clean up gobs of it since they started using it decades ago. This is something I'm currently wondering about. I have a fridge-like thermo-electric cooler than has two sections, top and bottom, with different temperatures. The top suddenly stopped getting cool at all, so I took it apart to figure out why. The fans and voltages were all there so I broke down the heat sinks on the bad one to get to the Peltier device. With it isolated, I powered it up briefly and much to my surprise the Peltier device got hot real quickly with the opposite side getting cooler. So the device works, it has to be something with the heat sinks? They did use white goop on both sides, but very little and it was already dried. The heat sinks are milled flat where they make contact with the Peltier device, so my thinking is they need new goop. Looking around I found that Star heat sink compound is about the best you can get, so I ordered some. It just arrived the other day so I'm planning to clean up the old goop, put on some new goop and hope for the best. I don't think too much would be an issue in this case, I want it as cold as possible. -- -Scott |
#31
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![]() "Lab1" .@... wrote in message ... On 1/19/2011 2:25 PM, Meat Plow wrote: Great dollops of that white goo between metal to metal thermally conductive surfaces. Overuse of that stuff is worse for thermal conductivity than none at all. I've clean up gobs of it since they started using it decades ago. This is something I'm currently wondering about. I have a fridge-like thermo-electric cooler than has two sections, top and bottom, with different temperatures. The top suddenly stopped getting cool at all, so I took it apart to figure out why. The fans and voltages were all there so I broke down the heat sinks on the bad one to get to the Peltier device. With it isolated, I powered it up briefly and much to my surprise the Peltier device got hot real quickly with the opposite side getting cooler. So the device works, it has to be something with the heat sinks? They did use white goop on both sides, but very little and it was already dried. The heat sinks are milled flat where they make contact with the Peltier device, so my thinking is they need new goop. Looking around I found that Star heat sink compound is about the best you can get, so I ordered some. It just arrived the other day so I'm planning to clean up the old goop, put on some new goop and hope for the best. I don't think too much would be an issue in this case, I want it as cold as possible. -- -Scott Too much of the stuff will be a problem whether you are trying to heat or cool. I have some major doubts that a thin coating of that stuff would be enough to make any major difference in the performance of peteler junction. Now on the other hand, if the heatsink is loose... That could give you some real issues. |
#32
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In article ,
Michael Kennedy mike@com wrote: They did use white goop on both sides, but very little and it was already dried. The heat sinks are milled flat where they make contact with the Peltier device, so my thinking is they need new goop. Too much of the stuff will be a problem whether you are trying to heat or cool. I have some major doubts that a thin coating of that stuff would be enough to make any major difference in the performance of peteler junction. Now on the other hand, if the heatsink is loose... That could give you some real issues. Michael is quite correct. The thing about heatsink compound, is that you should only use a *very* thin layer, and use it between surfaces which are already flat and well-fitting. Adding a thicker layer of heatsink compound than is necessary, will actually reduce thermal conductivity. You want as much direct metal-to-metal or metal-to-ceramic contact as you can get - enthusiasts who "overclock" their PCs will often flatten and polish the top of the CPU and the bottom of the heatsink to increase direct contact. A *thin* smear of heatsink compound is appropriate... just enough to fill the remaining gaps between the heatsink and the heat-sunk :-). You almost want to smear it on, and then wipe most of it off gently with a single-edged razor blade, so that there is no excess buildup between the two surfaces. And, yes, if the heatsink actually comes loose from the Peltier junction (e.g. if it was originally spring-clipped in place, and the clips are loose or have fatigued and lost pressure) then you've got problems... you'll get a layer of air between the two surfaces, and thermal conductivity will become quite poor. Adding a thicker layer of goop to try to fill the gap isn't the right thing to do - instead, fix whatever caused the devices to become loose, clean the surfaces, reapply a *thin* layer of compound, and secure the devices back together with the proper amount of pressure. If there was (apparently) nothing holding the two surfaces together - no clips or retainers - then you're probably dealing with a "thermally conductive adhesive". Some of these are good, some are poor... and you'll have to strip off all of the remains, and then reapply (again) a very thin layer of a suitable thermal adhesive, and fasten the parts back together with appropriate pressure until the adhesive cures. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
#33
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On 1/20/2011 2:03 AM, Dave Platt wrote:
And, yes, if the heatsink actually comes loose from the Peltier junction (e.g. if it was originally spring-clipped in place, and the clips are loose or have fatigued and lost pressure) then you've got problems... you'll get a layer of air between the two surfaces, and thermal conductivity will become quite poor. Adding a thicker layer of goop to try to fill the gap isn't the right thing to do - instead, fix whatever caused the devices to become loose, clean the surfaces, reapply a *thin* layer of compound, and secure the devices back together with the proper amount of pressure. I agree. The assembly goes like this: Small heat sink (cold side) - square plastic gasket with embedded rubber seal that doesn't physically touch anything - square block of Styrofoam with a square cutout in the middle - Peltier device - foam tape around the styrofoam - large heat sink. To screws go through everything on either side of the Peltier to sandwich it all together. And oddly they hot-glued the ends of the screws and nuts. This is obviously made in China, everything is pretty crudely manufactured and assembled, heat sink fins were mashed together in spots. I didn't think to check the tightness of those two screws when I took it apart, but I bet you are right and they weren't nearly tight enough. I'm going to rebuild the 2nd one while I'm at it and will check the tightness after I pry off all the hot glue... -- -Scott |
#34
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On Jan 19, 6:54*am, "N_Cook" wrote:
Great dollops of that white goo between metal to metal thermally conductive surfaces. Worse, hotmelt glue or cyanoacrylate on a solder joint. Hit it with the iron, and the tip seems like it'll NEVER get clean again. |
#35
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On 1/19/2011 5:05 PM, whit3rd wrote:
On Jan 19, 6:54 am, wrote: Great dollops of that white goo between metal to metal thermally conductive surfaces. Worse, hotmelt glue or cyanoacrylate on a solder joint. Hit it with the iron, and the tip seems like it'll NEVER get clean again. Oh yeah, GM delco car radios, IMPOSSIBLE to work on those circuit boards due to some resin/glue coating on everything. -- -Scott |
#36
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![]() "Nutcase Kook " Great dollops of that white goo between metal to metal thermally conductive surfaces. Heatsink to metal casing in amplifiers etc. I'm not sure why it is even necessary with perhaps 20 square inches of contact and bolts between. ** Err - because there are always large areas between fasteners that have air gaps. I always wipe away with paper etc on first parting but always some gets on my clothing ** When you separate the metal parts - cover them both with " Glad Wrap". It later peels off easily and leaves almost all the white grease behind. Anyone here remember the Bose 1800 /1801 amplifiers ?? Discovered this trick when servicing those horrible POS. ...... Phil |
#37
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On 19/01/2011 23:05, Phil Allison wrote:
Anyone here remember the Bose 1800 /1801 amplifiers ?? Remember them! I've still got one, still works too. Not that I would use it for anything other than a door stop mind. Ron |
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