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Pressing drill rod into brass.
I make spinning tools for a lady who owns a sheep farm. They look like
a long slender top with a 3/32" drill rod shaft and a 1" diameter x ..100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. The problem is that some of them do not stay fixed in the hole. The hole is drilled and then reamed .0005 undersize and then the brass is tapped onto the shaft using another piece of brass the same diameter with a hole drilled in the center for the shaft to pass through. I think some of the brass is being displaced by the much harder steel shaft and it will spin on the shaft. I have tried everything from Loctite to Super Glue to Epoxy. Loctite was hit and miss even thought the brass and shaft were thouroughly cleaned prior to assembly. Super Glue was the same but left an opaque film. Epoxy was too unsightly and the customer did not like it. I know that a shrink fit would be best but too much heat discolors the brass. All I have to heat the brass is a toaster oven I use for tempering. It was a max temp of around 500 degrees F. The other problem is how to shrink the drill rod. I do not want to have to deal with dry ice or liquid nitrogen to do this. It is too expensive to get those and the profit margin on these is not there. Any suggestion on how to put these together would be greatly appreciated. The bonding agent cannot be seen on the outside of the piece. I also tried soldering but it did not look too good. Thanks, Steve |
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wrote in message
oups.com... | I make spinning tools for a lady who owns a sheep farm. They look like | a long slender top with a 3/32" drill rod shaft and a 1" diameter x | .100 thick brass flywheel to generate the needed inertia to keep it | spinning. These are for spinning cotton fibers. | | The problem is that some of them do not stay fixed in the hole. The | hole is drilled and then reamed .0005 undersize and then the brass is | tapped onto the shaft using another piece of brass the same diameter | with a hole drilled in the center for the shaft to pass through. I | think some of the brass is being displaced by the much harder steel | shaft and it will spin on the shaft. For the existing shafts, would the customer object if you installed a roll pin on the shaft, flush with the flywheel? If you were to slot the flywheel slightly narrower than the pin, you could also have a mild interference fit, keeping it from sliding on the shaft. Swage the slot over the pin and it's now permanent. You didn't state whether the shaft goes all the way through the flywheel, but it would be good to use two pins if that were the case. I had a similar problem, but on a much bigger scale, and that was the simple only solution at the time. For futures, why not thread the shaft into the flywheel? Throw in a little locktite and it ought to hold great. You might have to retemper the drill rod to tap it, though. Not sure how to work with that stuff. |
I am one of those that would say braze them. I would probably use
silver brazing. Don't know what kind of finish is needed. Would a wire brush finish be okay? Dan |
wrote in message
oups.com... I am one of those that would say braze them. I would probably use silver brazing. Don't know what kind of finish is needed. Would a wire brush finish be okay? Dan I'd just put a straight knurl on the end of the shaft. If it's fully hardened, forget it, but if it's in a normalized or annealed condition, no problemo. It doesn't have to be pretty, just knurled enough to give it some tooth. -- Ed Huntress |
Loctite should work but you probably need to roughen the surface in the
area of the bond, an acid etch should do but a coarsish grit abrasive should do just as well. Same with the brass, roughen the bore with some abrasive on a rod. After abraiding chemically clean prior to bonding. Your best bet would be to email Loctite technical dept., that's what they're there for. Some of their products work better with with a thou or two of clearance, but they can give you a product number tolerances and surface preparation. Bernard R wrote: I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. The problem is that some of them do not stay fixed in the hole. The hole is drilled and then reamed .0005 undersize and then the brass is tapped onto the shaft using another piece of brass the same diameter with a hole drilled in the center for the shaft to pass through. I think some of the brass is being displaced by the much harder steel shaft and it will spin on the shaft. I have tried everything from Loctite to Super Glue to Epoxy. Loctite was hit and miss even thought the brass and shaft were thouroughly cleaned prior to assembly. Super Glue was the same but left an opaque film. Epoxy was too unsightly and the customer did not like it. I know that a shrink fit would be best but too much heat discolors the brass. All I have to heat the brass is a toaster oven I use for tempering. It was a max temp of around 500 degrees F. The other problem is how to shrink the drill rod. I do not want to have to deal with dry ice or liquid nitrogen to do this. It is too expensive to get those and the profit margin on these is not there. Any suggestion on how to put these together would be greatly appreciated. The bonding agent cannot be seen on the outside of the piece. I also tried soldering but it did not look too good. Thanks, Steve |
wrote in message
oups.com... I have tried everything from Loctite to Super Glue to Epoxy. Loctite was hit and miss even thought the brass and shaft were thouroughly cleaned prior to assembly. Steve, what type of Loctite did you use? There are a number of different types of Loctite for different applications. What you want is Loctite 640 Sleeve Retainer. Here is the description from the Technical Data Sheet: Quote:
recommend that you use automotive brake cleaner (or similar solvent) to remove all traces of grease, oil, and cutting fluids. Here are the assembly instructions for press-fit parts: Quote:
- Michael |
Drill a piliot hole in the end of the steel, then insert the rod in the
bradd with Loctite, then use a sharp centerpunch to expand the shaft to make is a tight fit in the flywheel. Done right, it will not come out |
On 13 May 2005 20:41:39 -0700, "
wrote: I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. The problem is that some of them do not stay fixed in the hole. The hole is drilled and then reamed .0005 undersize and then the brass is tapped onto the shaft using another piece of brass the same diameter with a hole drilled in the center for the shaft to pass through. I think some of the brass is being displaced by the much harder steel shaft and it will spin on the shaft. I have tried everything from Loctite to Super Glue to Epoxy. Loctite was hit and miss even thought the brass and shaft were thouroughly cleaned prior to assembly. Super Glue was the same but left an opaque film. Epoxy was too unsightly and the customer did not like it. I know that a shrink fit would be best but too much heat discolors the brass. All I have to heat the brass is a toaster oven I use for tempering. It was a max temp of around 500 degrees F. The other problem is how to shrink the drill rod. I do not want to have to deal with dry ice or liquid nitrogen to do this. It is too expensive to get those and the profit margin on these is not there. Any suggestion on how to put these together would be greatly appreciated. The bonding agent cannot be seen on the outside of the piece. I also tried soldering but it did not look too good. Thanks, Steve Chamfer or slightly taper the rod so that it slides into the brass rather than "broaching" a new diameter? Also, as was already suggested, experiment with smaller reamed holes in the brass. You may need to go down to .002" undersize. Randy |
Press fit with .002" interference? Use a slight taper on the end to
avoid shearing off the inside of the brass. Shrink fitting is not an option, the 3/32" shaft is way too small to get much of any size differential. wrote: I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. The problem is that some of them do not stay fixed in the hole. The hole is drilled and then reamed .0005 undersize and then the brass is tapped onto the shaft using another piece of brass the same diameter with a hole drilled in the center for the shaft to pass through. I think some of the brass is being displaced by the much harder steel shaft and it will spin on the shaft. I have tried everything from Loctite to Super Glue to Epoxy. Loctite was hit and miss even thought the brass and shaft were thouroughly cleaned prior to assembly. Super Glue was the same but left an opaque film. Epoxy was too unsightly and the customer did not like it. I know that a shrink fit would be best but too much heat discolors the brass. All I have to heat the brass is a toaster oven I use for tempering. It was a max temp of around 500 degrees F. The other problem is how to shrink the drill rod. I do not want to have to deal with dry ice or liquid nitrogen to do this. It is too expensive to get those and the profit margin on these is not there. Any suggestion on how to put these together would be greatly appreciated. The bonding agent cannot be seen on the outside of the piece. I also tried soldering but it did not look too good. Thanks, Steve |
In article .com,
" wrote: I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. [snip] Any suggestion on how to put these together would be greatly appreciated. The bonding agent cannot be seen on the outside of the piece. I also tried soldering but it did not look too good. I would think that soft soldering would work perfectly, and is easily a factor of ten stronger than any epoxy or loctite compound, so a soldered connection will last forever in such service. So, I would suggest figuring out why the soldering didn't "look good". Hand feeding the solder may be the issue. Setting things up so that only the correct amount of solder is used can help a great deal. The standard trick is to pre-tin the steel using tinners flux (zinc chloride in muriatic acid), wash the vestiges of the tinners flux off with hot water, polish the hole in the brass with a rolled-up piece of sandpaper or sandcloth, assemble, smear with plumbers grease flux, put a small circle of solder wire right at the junction between steel shaft and brass wheel, set up so it does not need to be touched or manipulated while hot, and heat the wheel (not the rod) up with a large propane torch. (Air acetylene would be OK, but oxy-anything is too intense. That said, faster is better, as there will be less burn and scale to clean up.) When the solder melts and flows, remove torch and allow it all to cool. Clean off with solvent (to get the grease flux) and steel wool (or the equivalent scotchbrite pad) used wet. If necessary to get the tinned steel rod to fit into the hole, wipe excess solder off the rod while it's still hot, using a damp paper towel. Eutectic solder (63 tin, 37 lead) melts at 371 degrees C, the lowest, and is very shiney. The tin-lead-silver solders are also very nice looking, strong, and easy to use. In radio work, 2% silver is very common, and easy to get. Likewise 63-37 eutectic solder. Joe Gwinn |
One thing that nobody else has mentioned is to heat the brass flywheel to
maybe 400F or higher before putting it on the shaft. You will want to make the hole only big enough to just fit on the shaft at that temp and the brass will shrink considerably when it cools and hold hard. It will also help to knurl the part of the shaft were the flywheel goes and this can quickly be done with the edge of a fine file. You don't need to do a real deep knurl to make it hold well. When you do the pressing, a jig to hold the rod so that you can drive the flywheel solidly to the spot where it belings will help. Even just a hole in a block of wood if you need the flywheel in from the end an inch or so will do fine, depending upon how accurately you need to have the flywheel in a particular place. -- Why isn't there an Ozone Hole at the NORTH Pole? |
Mill a pair of small slots 180 degrees out on the shaft in the area of the flywheel. Install the flywheel and use a punch to peen a small area of the brass into the slots. locking it in place. Or vertical knurl in the same area and press the parts together with a tighter fit (.002 undersized or so) -- Steve Williams wrote in message oups.com... I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. The problem is that some of them do not stay fixed in the hole. The hole is drilled and then reamed .0005 undersize and then the brass is tapped onto the shaft using another piece of brass the same diameter with a hole drilled in the center for the shaft to pass through. I think some of the brass is being displaced by the much harder steel shaft and it will spin on the shaft. I have tried everything from Loctite to Super Glue to Epoxy. Loctite was hit and miss even thought the brass and shaft were thouroughly cleaned prior to assembly. Super Glue was the same but left an opaque film. Epoxy was too unsightly and the customer did not like it. I know that a shrink fit would be best but too much heat discolors the brass. All I have to heat the brass is a toaster oven I use for tempering. It was a max temp of around 500 degrees F. The other problem is how to shrink the drill rod. I do not want to have to deal with dry ice or liquid nitrogen to do this. It is too expensive to get those and the profit margin on these is not there. Any suggestion on how to put these together would be greatly appreciated. The bonding agent cannot be seen on the outside of the piece. I also tried soldering but it did not look too good. Thanks, Steve ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
"Ignoramus633" wrote in message ... On 13 May 2005 20:41:39 -0700, wrote: I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. does that lady grow cotton in addition to sheep? I am confused. Her husband likes her to make sexy cotton undies for the sheep. |
On Sat, 14 May 2005 19:33:30 -0400, the inscrutable "ATP*"
spake: "Ignoramus633" wrote in message ... On 13 May 2005 20:41:39 -0700, wrote: I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. does that lady grow cotton in addition to sheep? I am confused. Her husband likes her to make sexy cotton undies for the sheep. I thought maybe they was them Suthuhn sheeps. Then again, cotton waders would be more comfy on those hot, humid nights. ------ We're born hungry, wet, 'n naked, and it gets worse from there. - http://diversify.com Website Application Programming - |
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In article ,
Ned Simmons wrote: In article JoeGwinn-C1340A.12261514052005 @comcast.dca.giganews.com, says... In article .com, " wrote: [snip] I would think that soft soldering would work perfectly, and is easily a factor of ten stronger than any epoxy or loctite compound, so a soldered connection will last forever in such service. A factor of 2 would be closer. Solder metal is far stronger than epoxy or loctite, especially silver-bearing solder. Even crappy metal is ~20,000 psi, versus ~2,000 psi for plastics. Solder does creep, but so do plastics, although epoxy isn't bad. Solder, being soft, is less brittle. The really strong epoxies, such as those used for repair of aluminium airplanes, needs lots of process and care, and high-temperature cure, and are not all that easily available. Even so, the metal is stronger. I suspect the reason that Loctite didn't work was that there was no clearance between the parts. Solder's not going to work any better under those circumstances. This is a good point. Both require a few thousandths of an inch of clearance to work well, although solder bridges gaps better. But anyway, soft solder ought to work well. Joe Gwinn |
On a 3/16" shaft/hole, 400 F will give you an expansion of about .0006".
Not enough to make it worth the hassle of trying to assemble it. Bob May wrote: One thing that nobody else has mentioned is to heat the brass flywheel to maybe 400F or higher before putting it on the shaft. You will want to make the hole only big enough to just fit on the shaft at that temp and the brass will shrink considerably when it cools and hold hard. It will also help to knurl the part of the shaft were the flywheel goes and this can quickly be done with the edge of a fine file. You don't need to do a real deep knurl to make it hold well. When you do the pressing, a jig to hold the rod so that you can drive the flywheel solidly to the spot where it belings will help. Even just a hole in a block of wood if you need the flywheel in from the end an inch or so will do fine, depending upon how accurately you need to have the flywheel in a particular place. -- Why isn't there an Ozone Hole at the NORTH Pole? |
wrote:
I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. The problem is that some of them do not stay fixed in the hole. The hole is drilled and then reamed .0005 undersize and then the brass is tapped onto the shaft using another piece of brass the same diameter with a hole drilled in the center for the shaft to pass through. I think some of the brass is being displaced by the much harder steel shaft and it will spin on the shaft. I have tried everything from Loctite to Super Glue to Epoxy. Loctite was hit and miss even thought the brass and shaft were thouroughly cleaned prior to assembly. Super Glue was the same but left an opaque film. Epoxy was too unsightly and the customer did not like it. I know that a shrink fit would be best but too much heat discolors the brass. All I have to heat the brass is a toaster oven I use for tempering. It was a max temp of around 500 degrees F. The other problem is how to shrink the drill rod. I do not want to have to deal with dry ice or liquid nitrogen to do this. It is too expensive to get those and the profit margin on these is not there. Any suggestion on how to put these together would be greatly appreciated. The bonding agent cannot be seen on the outside of the piece. I also tried soldering but it did not look too good. Thanks, Steve Water, Ice and Salt. The salt drops the freezing point of water. IIRC, Vodka helps in the melting and dropping the temp. Martin -- Martin Eastburn @ home at Lion's Lair with our computer lionslair at consolidated dot net NRA LOH, NRA Life NRA Second Amendment Task Force Charter Founder ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
On 13 May 2005 20:41:39 -0700, "
wrote: I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. The problem is that some of them do not stay fixed in the hole. The hole is drilled and then reamed .0005 undersize and then the brass is tapped onto the shaft using another piece of brass the same diameter with a hole drilled in the center for the shaft to pass through. I think some of the brass is being displaced by the much harder steel shaft and it will spin on the shaft. I have tried everything from Loctite to Super Glue to Epoxy. Loctite was hit and miss even thought the brass and shaft were thouroughly cleaned prior to assembly. Super Glue was the same but left an opaque film. Epoxy was too unsightly and the customer did not like it. I know that a shrink fit would be best but too much heat discolors the brass. All I have to heat the brass is a toaster oven I use for tempering. It was a max temp of around 500 degrees F. The other problem is how to shrink the drill rod. I do not want to have to deal with dry ice or liquid nitrogen to do this. It is too expensive to get those and the profit margin on these is not there. Any suggestion on how to put these together would be greatly appreciated. The bonding agent cannot be seen on the outside of the piece. I also tried soldering but it did not look too good. Thanks, Steve I'm surprised that Loctite didn't do it. Which Loctite product did you use? The threadlock stuff from the car parts store (271 and 454) may not work well here, but I'll bet that Loctite 609 or 680 would do the job. It works even better if you use their primer. |
On Sat, 14 May 2005 12:26:15 -0400, Joseph Gwinn
wrote: In article .com, " wrote: I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. [snip] Any suggestion on how to put these together would be greatly appreciated. The bonding agent cannot be seen on the outside of the piece. I also tried soldering but it did not look too good. I would think that soft soldering would work perfectly, and is easily a factor of ten stronger than any epoxy or loctite compound, so a soldered connection will last forever in such service. So, I would suggest figuring out why the soldering didn't "look good". Hand feeding the solder may be the issue. Setting things up so that only the correct amount of solder is used can help a great deal. The standard trick is to pre-tin the steel using tinners flux (zinc chloride in muriatic acid), wash the vestiges of the tinners flux off with hot water, polish the hole in the brass with a rolled-up piece of sandpaper or sandcloth, assemble, smear with plumbers grease flux, put a small circle of solder wire right at the junction between steel shaft and brass wheel, set up so it does not need to be touched or manipulated while hot, and heat the wheel (not the rod) up with a large propane torch. (Air acetylene would be OK, but oxy-anything is too intense. That said, faster is better, as there will be less burn and scale to clean up.) When the solder melts and flows, remove torch and allow it all to cool. Clean off with solvent (to get the grease flux) and steel wool (or the equivalent scotchbrite pad) used wet. If necessary to get the tinned steel rod to fit into the hole, wipe excess solder off the rod while it's still hot, using a damp paper towel. Eutectic solder (63 tin, 37 lead) melts at 371 degrees C, the lowest, and is very shiney. The tin-lead-silver solders are also very nice looking, strong, and easy to use. In radio work, 2% silver is very common, and easy to get. Likewise 63-37 eutectic solder. Joe Gwinn Adding to Joe's comments: I'd use a tin silver solder like Harris Staybrite. Though a low temperature solder (430F), it's considerably stronger than lead-tin solder and it's very fluid when it melts. No need to pre-tin the rod, but I'd lightly countersink the flywheel on both sides to provide a fillet area. |
In article JoeGwinn-79C5EE.21542814052005
@comcast.dca.giganews.com, says... In article , Ned Simmons wrote: In article JoeGwinn-C1340A.12261514052005 @comcast.dca.giganews.com, says... In article .com, " wrote: [snip] I would think that soft soldering would work perfectly, and is easily a factor of ten stronger than any epoxy or loctite compound, so a soldered connection will last forever in such service. A factor of 2 would be closer. Solder metal is far stronger than epoxy or loctite, especially silver-bearing solder. Even crappy metal is ~20,000 psi, versus ~2,000 psi for plastics. 20 ksi in shear is about right for softer grades of aluminum. 5-10 ksi shear strength is more typical than 2 ksi for engineering plastics. Solder does creep, but so do plastics, although epoxy isn't bad. Solder, being soft, is less brittle. The really strong epoxies, such as those used for repair of aluminium airplanes, needs lots of process and care, and high-temperature cure, and are not all that easily available. Even so, the metal is stronger. I suspect the reason that Loctite didn't work was that there was no clearance between the parts. Solder's not going to work any better under those circumstances. This is a good point. Both require a few thousandths of an inch of clearance to work well, although solder bridges gaps better. But anyway, soft solder ought to work well. As I said, soft solder is only about twice as strong in shear as the most common Loctite retaining compounds. About 8000 psi for 63/37 in a proper joint... http://www.matweb.com/search/SpecificMaterial.asp? bassnum=MLSS63 And around 4000 psi for Loctite 680... http://www.matweb.com/search/SpecificMaterial.asp? bassnum=PLOCT127 Either one, if properly applied, should be more that strong enough. Ned Simmons |
In article ,
Ned Simmons wrote: In article JoeGwinn-79C5EE.21542814052005 @comcast.dca.giganews.com, says... In article , Ned Simmons wrote: In article JoeGwinn-C1340A.12261514052005 @comcast.dca.giganews.com, says... In article .com, " wrote: [snip] I would think that soft soldering would work perfectly, and is easily a factor of ten stronger than any epoxy or loctite compound, so a soldered connection will last forever in such service. A factor of 2 would be closer. Solder metal is far stronger than epoxy or loctite, especially silver-bearing solder. Even crappy metal is ~20,000 psi, versus ~2,000 psi for plastics. 20 ksi in shear is about right for softer grades of aluminum. 5-10 ksi shear strength is more typical than 2 ksi for engineering plastics. We're mixing tensile and shear strengths, but I'll grant your point that the ratio may not be 10:1 any more. Although, most of the plastics one deals with are not quite so good as those "engineering plastics". Solder does creep, but so do plastics, although epoxy isn't bad. Solder, being soft, is less brittle. The really strong epoxies, such as those used for repair of aluminium airplanes, needs lots of process and care, and high-temperature cure, and are not all that easily available. Even so, the metal is stronger. I suspect the reason that Loctite didn't work was that there was no clearance between the parts. Solder's not going to work any better under those circumstances. This is a good point. Both require a few thousandths of an inch of clearance to work well, although solder bridges gaps better. But anyway, soft solder ought to work well. As I said, soft solder is only about twice as strong in shear as the most common Loctite retaining compounds. About 8000 psi for 63/37 in a proper joint... http://www.matweb.com/search/SpecificMaterial.asp? bassnum=MLSS63 And around 4000 psi for Loctite 680... http://www.matweb.com/search/SpecificMaterial.asp? bassnum=PLOCT127 I suspect one must use a primer to achieve this strength. Either one, if properly applied, should be more than strong enough. That seems likely; the service doesn't seem that severe. But... On a somewhat comic note, I recently had the task of attaching the point of a telescoping pointer (looks like a radio antenna, used in lectures) for a colleague. The point would unscrew in mid-lecture and fly away, sometimes hitting someone. Sometimes me, so I "borrowed" the offending pointer and took it home for repair. Epoxy failed -- too much leverage between point and rod, and the bond was almost immediately broken when the lecturer smacked the pointer against the screen, to emphasize a point. What worked, and survived, was 63-37 solder. So, I don't know that I really believe that the ratio of actual bond strength is only 2:1 in practice, despite the datasheets, although I cannot put a number on it. Joe Gwinn |
In article ,
Don Foreman wrote: On Sat, 14 May 2005 12:26:15 -0400, Joseph Gwinn wrote: In article .com, " wrote: I make spinning tools for a lady who owns a sheep farm. They look like a long slender top with a 3/32" drill rod shaft and a 1" diameter x .100 thick brass flywheel to generate the needed inertia to keep it spinning. These are for spinning cotton fibers. [snip] [snip] If necessary to get the tinned steel rod to fit into the hole, wipe excess solder off the rod while it's still hot, using a damp paper towel. Eutectic solder (63 tin, 37 lead) melts at 371 degrees C, the lowest, and is very shiney. The tin-lead-silver solders are also very nice looking, strong, and easy to use. In radio work, 2% silver is very common, and easy to get. Likewise 63-37 eutectic solder. Joe Gwinn Adding to Joe's comments: I'd use a tin silver solder like Harris Staybrite. Though a low temperature solder (430F), it's considerably stronger than lead-tin solder and it's very fluid when it melts. No need to pre-tin the rod, but I'd lightly countersink the flywheel on both sides to provide a fillet area. I haven't tried silver-bearing solder on steel, but I would suspect that the pre-tinning is still a good idea, especially as the actual soldering step is done without touching anything. I also note that the 63-37 solder melts at 371 degrees F (not C), so it could be melted in a toaster oven, in a low-tech version of furnace soldering. My main fear would be that this would heat things too slowly, causing the flux to boil away before reaching soldering temperature, so I'd use a small soft-flamed torch. Joe Gwinn |
Ever think of keyway broaching the flywheel and milling a slot on the
shaft. Maybe use 1/16" square key, or some of the key with a large size on half for the flywheel and smaller for the shaft. You could then solder or epoxy the key in place, and a slot rather than keyed shaft would also prevent the key ever falling out. |
"DeepDiver" wrote in message ... wrote in message oups.com... I have tried everything from Loctite to Super Glue to Epoxy. Loctite was hit and miss even thought the brass and shaft were thouroughly cleaned prior to assembly. Steve, what type of Loctite did you use? There are a number of different types of Loctite for different applications. What you want is Loctite 640 Sleeve Retainer. Here is the description from the Technical Data Sheet: [quote] Product 640 is designed for the bonding of cylindrical fitting parts. The product cures when confined in the absence of air between close fitting metal surfaces and prevents loosening and leakage from shock and vibration. Good stuff, I used that to seat a sleeve for a diesel injector in my UD truck. |
On Sun, 15 May 2005 10:50:36 -0400, Joseph Gwinn
wrote: I haven't tried silver-bearing solder on steel, but I would suspect that the pre-tinning is still a good idea, especially as the actual soldering step is done without touching anything. I also note that the 63-37 solder melts at 371 degrees F (not C), so it could be melted in a toaster oven, in a low-tech version of furnace soldering. My main fear would be that this would heat things too slowly, causing the flux to boil away before reaching soldering temperature, so I'd use a small soft-flamed torch. The 430F tin-silver solder readily wets steel, stainless, copper and brass. 63-37 doesn't wet steel nearly as readily, nor is it nearly as strong. See http://users.goldengate.net/~dforeman/spinner/ for a quicky experiment with 3/32" drillrod in a 1" dia brass wheel. I used a Lil' Torch, #6 tip, running oxypropane. I countersunk the hole to provide a "collar" of solder. You can see how the solder forms a small concave fillet on the drillrod, proof that it is wetting it nicely. 63-37 will wet copper or brass this way, but not steel. |
That's a nice job! We just did some similar sized gears (large to
small) with silphos, really ugly wick up into the smaller gear teeth. Don Foreman wrote: On Sun, 15 May 2005 10:50:36 -0400, Joseph Gwinn wrote: I haven't tried silver-bearing solder on steel, but I would suspect that the pre-tinning is still a good idea, especially as the actual soldering step is done without touching anything. I also note that the 63-37 solder melts at 371 degrees F (not C), so it could be melted in a toaster oven, in a low-tech version of furnace soldering. My main fear would be that this would heat things too slowly, causing the flux to boil away before reaching soldering temperature, so I'd use a small soft-flamed torch. The 430F tin-silver solder readily wets steel, stainless, copper and brass. 63-37 doesn't wet steel nearly as readily, nor is it nearly as strong. See http://users.goldengate.net/~dforeman/spinner/ for a quicky experiment with 3/32" drillrod in a 1" dia brass wheel. I used a Lil' Torch, #6 tip, running oxypropane. I countersunk the hole to provide a "collar" of solder. You can see how the solder forms a small concave fillet on the drillrod, proof that it is wetting it nicely. 63-37 will wet copper or brass this way, but not steel. |
On Mon, 16 May 2005 17:49:02 GMT, RoyJ wrote:
That's a nice job! We just did some similar sized gears (large to small) with silphos, really ugly wick up into the smaller gear teeth. I wonder if Heat Fence (American Chemical & Flux, available at welding stores) gooped into the teeth would prevent brazing alloy from wicking where you don't want it. I don't have any gears handy or I'd try it. |
"Ignoramus633" wrote in message ... On 13 May 2005 20:41:39 -0700, wrote: does that lady grow cotton in addition to sheep? I am confused. Well it is quite an interesting thing, you may have heard of cotton wool, but wool cotton was originally made by Benjamin Franklin to give the southern states an alternative to growing cotton and to hopefully lesson their reliance on slave labor. The idea never gained momentum however as the process required a "sheep gin" the damn sheep would then get so sloshed that they were too difficult to manage in that condition. -- Roger Shoaf About the time I had mastered getting the toothpaste back in the tube, then they come up with this striped stuff. |
"Roger Shoaf" wrote in message
... "Ignoramus633" wrote in message ... On 13 May 2005 20:41:39 -0700, wrote: does that lady grow cotton in addition to sheep? I am confused. Well it is quite an interesting thing, you may have heard of cotton wool, but wool cotton was originally made by Benjamin Franklin to give the southern states an alternative to growing cotton and to hopefully lesson their reliance on slave labor. The idea never gained momentum however as the process required a "sheep gin" the damn sheep would then get so sloshed that they were too difficult to manage in that condition. -- Roger Shoaf Haha! I like the way you think, Roger. d8-) -- Ed Huntress |
In article ,
Don Foreman wrote: On Sun, 15 May 2005 10:50:36 -0400, Joseph Gwinn wrote: I haven't tried silver-bearing solder on steel, but I would suspect that the pre-tinning is still a good idea, especially as the actual soldering step is done without touching anything. I also note that the 63-37 solder melts at 371 degrees F (not C), so it could be melted in a toaster oven, in a low-tech version of furnace soldering. My main fear would be that this would heat things too slowly, causing the flux to boil away before reaching soldering temperature, so I'd use a small soft-flamed torch. The 430F tin-silver solder readily wets steel, stainless, copper and brass. 63-37 doesn't wet steel nearly as readily, nor is it nearly as strong. See http://users.goldengate.net/~dforeman/spinner/ for a quicky experiment with 3/32" drillrod in a 1" dia brass wheel. I used a Lil' Torch, #6 tip, running oxypropane. I countersunk the hole to provide a "collar" of solder. You can see how the solder forms a small concave fillet on the drillrod, proof that it is wetting it nicely. 63-37 will wet copper or brass this way, but not steel. Looks really nice. Maybe a bit too much solder used, but that's a cosmetic issue only. How long did the actual soldering take? What is the percentage composition of the tin-silver solder you used, and the maker? Joe Gwinn |
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