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Removing really stuck flat head screws...
We use some decent flat head screws on our units and I've run into a strange
problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
You need one of those Bob the Butthole Villa / Crapsman thing a ma
jiggies.......called a screw out IIRC.... REMEMBER: "This is worth repeating for benefit of al newbies! Jo Ann asked Dr. Sooooooooooooooooolow to remind people that while she has retired from selling GF (and sold the business to Ken Fischer http://dandyorandas.com/) she has NOT retired from helping people with sick GF and koi FOR FREE. 251-649-4790 phoning is best for diagnosis. but, can try email put "help sick fish" in subject. Get your fish at Dandy Orandas Dandy Orandas Dandy Orandas........you guys got that DANDY ORANDAS |
My only thought is that they are overtorqued. What size are they?
I have problems with #10's I use , but it usually shreds the socket or the allen key. I don't know the specifics, but follow me here. you have a rubber gasket? if they are being tightened unevenly, rather than as you would a cylinder head, the first ones tightened might be really overtorqued when you tighten the last as the cover levers down. Perhaps the galvy is grabbing the head; never seize or clean the plating out of the c'sink. They aren't metric are they? 90 degree in an 82 csink? Try using a small impact gun [3/8 drive or chinese 1/2 drive] to exract them, sometimes the knock will break them loose Joe wrote: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
In article , news.ind.net.spamtrap1
@yunx.com says... We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. I've run into this when installing cap screws into aluminum that's been anodized after the holes were drilled and tapped. I've always assumed it was due to the hard anodized surface having a bit of tooth and biting into the surface of the screw. As you imply, it seems to take a few minutes for the effect to take place. The fact that you have less problem with painted material is puzzling. Could it be that the screw is seizing in the tapped hole, but the paint is acting as a lubricant making it a bit easier to break it free? Have you tried never-seez in the tapped hole and under the head? What about plated fasteners? I imagine this is a well known phenomenon. Perhaps a call to Allen or Holokrome would get you an answer. Ned Simmons |
There is a product used in aerospace, locally we call it a "lester
tool." More or less it is a tee shaped tool, with the perpendicular part being just a metal rod for a handle. One end is a .401 rivet gun/air hammer shank and the other end has a recess that takes a 1/4" hex bit. The idea is that while pounding the fastener one turns the handle. Works wonders on paint filled fasteners on external panels which really don't want to come out for assorted reasons. You can likely make one; they're nothing fancy. You need to have a clear path for the impact to flow through the part or your gun will destroy it. Never used one on an air hammer, I have to admit, but it's the best thing for this type of thing. The "X-Out" screw removal tool from Sears (I think they sell that under their own name) will not do the trick, you have to break up the stiction in the joint, that tool only exists to work with stripped screwdriver recesses. We tried them on titanium fasteners and despite the manufacturers assurances, they just removed metal from the recess, making us drill the screw out anyway, which is a royal pain when you panel has over a hundred screws and the one that stripped was the last one you put in! "Joe" wrote in message ... | We use some decent flat head screws on our units and I've run into a strange | problem. When we tighten them into the aluminum housings, they hold a | galvanized plate in place. After about 10 minutes of being on there, they | are almost impossible to get off. | | We have turned the highest quality allen keys we can find into pretzels and | have stripped many using impact and a shorter length. Sometimes we have | success by using a chisel to "spin" the flat head loose but that's the | Neanderthal method I'd like to avoid... Even that fails 50% of the time. | We can't use heat because there is a rubber seal in the aluminum very close. | | The flat head actually grabs onto the galv. plate so well that our customers | (and us!) have to drill them out 8 out of 10 times we need to remove them... | | Anyone know of a super allen key or some other method of removing these that | might work? We know that when we use painted plates, we have less of a | problem and have considered painting the countersink of each flat head hole, | but that's crazy in the big scheme of things... | | Thoughts, wisdom and random visits from friends welcome. | | Regards, | Joe Agro, Jr. | http://www.autodrill.com | http://www.multi-spindle-heads.com | | V8013 | | My eBay: http://tinyurl.com/4hpnc | | |
On Wed, 12 Jan 2005 17:18:39 -0500, "Joe"
wrote: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. Have you tried any experiments with different screw materials? Stainless? Brass? |
"Joe" wrote in
: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc Never-sieze is your friend. One idea behind a flat head screw is to create a taper lock, which it does effectively, thereby eliminating the need for a locking mechanism. If these screws need to be removed for regular maintenance, you may wish to switch to a SHCS and suitable lockwasher. Or a button-head screw. -- Anthony You can't 'idiot proof' anything....every time you try, they just make better idiots. Remove sp to reply via email |
How about doctoring the countersink bit to a slightly off-angle to create
less surface area contact. Try counterboring the threaded holes a few thousandths to allow for a little deformation before it jams. How about a bigger tap drill. Are you alligning the length of the screw with the magnetic pole? "Joe" wrote in message ... We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
Hi Joe,
You didn't mention what material the screws are made from. If your using stainless switch if you can. Stainless socket head screws bugger more easily than black alloy or plated screws. I would suggest using a tiny dab of antisieze on the underside of the countersink. We use an antiseize from Swagelock called high purity goop. They make some impressive claims about this material and the best part is you only need a minute amount. Also you might look at going to Torx driver screws. These have a bit more bearing area and don't cam out as easily as hex keys. Good luck Tom Lipton |
On Wed, 12 Jan 2005 17:18:39 -0500, "Joe"
calmly ranted: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. Try using aluminum anti-sieze goop on the screw heads & threads when you reinstall. That should stop the problem on future boxes, but won't stop the need to drill out the existing problem boxes. You may be seeing a galvanic reaction there from the 3 dissimilar metals in contact with one another. (I had only one year of high school chemistry, so ask a real chemist for details.) ================================================== ======== Save the ||| http://diversify.com Endangered SKEETS! ||| Web Application Programming ================================================== ======== |
In article ,
"Joe" wrote: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. If you ignore basic chemistry you're going to suffer. Your problem description lays it out - you're plating the screw in place, for all intents and purposes, using the very nice battery formed by the aluminum, steel and zinc. Whoever designed this should be sent back to their high school chemistry teacher and forced to make an apology. You could try silicone grease, or anti-seize, but it's not likely to fully insulate the screw, so it will probably still fail. Change the materials and the problem will be reduced (as you have seen with the painted plate), or go away. Make the galvanized plate from aluminum, big reduction in problem. Make the screw aluminum as well, problem gone (but you'll need to be sure that the aluminum plate and the aluminum screws are designed in sizes that will do the job, if that is possible.) I've seen something similar inside a clothes-washing machine, and there I'm pretty sure that the materials choice was "malice aforethought" in making for planned obsolescence and non-repairability - the device held in place by an aluminum nut was warranteed for a very long time, but labor to replace it was not, and after a much shorter time than that warrantee, the nut was well on it's way to being impossibly corroded (the warrantee on the nut and the non-aluminum part it was screwed to was much shorter, but you could not get the long-warranteed part off once the short-warrantee parts had fused). -- Cats, Coffee, Chocolate...vices to live by |
)
I've seen something similar inside a clothes-washing machine, and there I'm pretty sure that the materials choice was "malice aforethought" in making for planned obsolescence and non-repairability - the device held in place by an aluminum nut was warranteed for a very long time, but labor to replace it was not, and after a much shorter time than that warrantee, the nut was well on it's way to being impossibly corroded (the warrantee on the nut and the non-aluminum part it was screwed to was much shorter, but you could not get the long-warranteed part off once the short-warrantee parts had fused). I seriously doubt that in a few minutes he is seeing the same thing as inside a washer. WE have been bolting steel to alumium for a hundred years the effects are long term |
That just made me think of something. If the bottom of the countersunk
hole doesn't match the profile of the fastener where the head meets the shank then there's is your problem. The fastener has a bit of an interference fit at the transition point, and right away the bearing surface under the fastener head isn't fully making contact because of it. However, the aluminum "flows" from the stress and lets the bearing surfaces bear down on each other. Add in a little galling from dissimilar metals, finish differences, and you have a bind. Apply a bit of oil or something on the fastener then run a couple in and back out just once in the time frame you have the issue with. Compare the bottoms of the holes with and without the fastener and look at the bottom of the hole at the transition point I mentioned above. If you see any profile changes, you likely have this issue. "Tom Gardner" wrote in message . com... | How about doctoring the countersink bit to a slightly off-angle to create | less surface area contact. Try counterboring the threaded holes a few | thousandths to allow for a little deformation before it jams. How about a | bigger tap drill. Are you alligning the length of the screw with the | magnetic pole? | | "Joe" wrote in message | ... | We use some decent flat head screws on our units and I've run into a | strange problem. When we tighten them into the aluminum housings, they | hold a galvanized plate in place. After about 10 minutes of being on | there, they are almost impossible to get off. | | We have turned the highest quality allen keys we can find into pretzels | and have stripped many using impact and a shorter length. Sometimes we | have success by using a chisel to "spin" the flat head loose but that's | the Neanderthal method I'd like to avoid... Even that fails 50% of the | time. We can't use heat because there is a rubber seal in the aluminum | very close. | | The flat head actually grabs onto the galv. plate so well that our | customers (and us!) have to drill them out 8 out of 10 times we need to | remove them... | | Anyone know of a super allen key or some other method of removing these | that might work? We know that when we use painted plates, we have less of | a problem and have considered painting the countersink of each flat head | hole, but that's crazy in the big scheme of things... | | Thoughts, wisdom and random visits from friends welcome. | | Regards, | Joe Agro, Jr. | http://www.autodrill.com | http://www.multi-spindle-heads.com | | V8013 | | My eBay: http://tinyurl.com/4hpnc | | | | |
yourname wrote: Lurking here for a while absorbing a wealth of information from the posters. Now it my turn to help. Thirty years ago it was common in the motorcycle circle to remove flat head phillips screws from the aluminum casting with a tool called an 'impact driver' (IIRC). It was/is a 6 inch long device that would accept a 5/16" hex bit, (phillips, slotted or allen) whatever you needed. Place it into the stubborn fastener, apply a slight torque and smack the end with a hammer. An internal cam provided more torque and the impact made sure the bit stayed in the screw head. It was quite effective on the soft screws Honda used to use to hold their cases togeather. Got mine from Sears and believe Harbor Fright may have them too. Hope this helps, Jerry |
|
In article ,
"Joe" wrote: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. My method of removing screws and such that are stuck is to hammer on the area immediately around the screw while twisting out. Moves the fastened surfaces towards each other and away from the screw head, possibly breaking the grip on the back of the screw. Doesn't work so well if it's the threads that are holding. A heavy steel slug with a hole down the middle slipped over the shaft of the screwdriver makes a nice impromptu slide hammer in just the right spot. -- B.B. --I am not a goat! thegoat4 at airmail dot net http://web2.airmail.net/thegoat4/ |
SNIP
Make the galvanized plate from aluminum, big reduction in problem. Make the screw aluminum as well, problem gone (but you'll need to be sure that the aluminum plate and the aluminum screws are designed in sizes that will do the job, if that is possible.) That's part of the problem. The plate needs to be real stiff so aliminum won't work. As it is, UPS Ground sometimes mangles them in shipment which always amazes me! As for the screw... I could try to find galv. screws but aluminum surely won't work. Black oxide seems the best answer for all intents and purposes... We need strength and most of the time, these things are there for the life of the machine which could be 5 years and 10 million holes... But if and when they need to be removed, they're a real headache. Not nearly as bad as if one came loose or broke though and destroyed belts, custom aluminum pulleys, guards, or worker's fingers! Really what I'm looking for is an allen key-type tool that won't degrade under stress like a full allen key will and/or one that I can apply either a shock to (impact or something) or lots of torque to remove the flat head. It's not a mjaor dilema, but I know how much everyone here loves to solve problems like this so I figured I'd ask and try to learn. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
CLIP
Thirty years ago it was common in the motorcycle circle to remove flat head phillips screws from the aluminum casting with a tool called an 'impact driver' (IIRC). CLIP Excellent advice. I have both a motorcycle and have tried this. The hex head on the tool stripped right off on a stubborn one we wound up drilling. Maybe I'll take a digital photo of the allen key I use to tighten the flat heads tomorrow so everyone can see the pretzel-like "twist" it still maintains from the last removal project. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
That just made me think of something. If the bottom of the countersunk
hole doesn't match the profile of the fastener where the head meets the shank then there's is your problem. The fastener has a bit of an interference fit at the transition point, and right away the bearing surface under the fastener head isn't fully making contact because of it. However, the aluminum "flows" from the stress and lets the bearing surfaces bear down on each other. SNIP Another very good point. We actually countersink the aluminum housing on the other side of teh plate to avoid this very problem. When we drill teh flat head off teh screw, the "shank" can be taken out with bare fingers... Most of the time so I'm 100% sure it is the flat head screw's angle on the flat head coutnersink within the plate. -- Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
You DO know that you can buy flat head lock washers don't you? They might help in getting the screws out as I think you have
too much contact area. R. Wink On Wed, 12 Jan 2005 17:18:39 -0500, "Joe" wrote: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
On Thu, 13 Jan 2005 01:39:00 GMT, Ecnerwal
wrote: In article , "Joe" wrote: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. If you ignore basic chemistry you're going to suffer. Your problem description lays it out - you're plating the screw in place, for all intents and purposes, using the very nice battery formed by the aluminum, steel and zinc. Whoever designed this should be sent back to their high school chemistry teacher and forced to make an apology. You could try silicone grease, or anti-seize, but it's not likely to fully insulate the screw, so it will probably still fail. Change the materials and the problem will be reduced (as you have seen with the painted plate), or go away. Make the galvanized plate from aluminum, big reduction in problem. Make the screw aluminum as well, problem gone (but you'll need to be sure that the aluminum plate and the aluminum screws are designed in sizes that will do the job, if that is possible.) snip Dad was a crop duster, and we worked on the planes a lot. Aluminum on aluminum will gall, or fuse, or otherwise permanently get together. Without the right antiseize, it would look like it had been welded. Pete Keillor |
Joe wrote: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Sounds like you need to talk to your materials engineer. The specs. may need to be changed. Bugs Thoughts, wisdom and random visits from friends welcome. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
You DO know that you can buy flat head lock washers don't you? They might
help in getting the screws out as I think you have too much contact area. Yup. Seriously considering that option. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
"Perhaps the galvy is grabbing the head; never seize or clean the plating
out of the c'sink." Try an "Impact Driver". It works by a hammer blow to the top of the tool, causing torque & shock at the same time. Also Id check the matching angles between the countersink & the screw. Experiment with changing the angle of the countersink so as to reduce or increase surface area. |
You should be able to find allen/hex drivers for 1/4" and/or 3/8" drive
handles.. ratchet, T-handle etc. The adapters with replaceable inserts can usually withstand a sharp impact inline with the fastener, such as a rap with a hammer. Quality U.S. made hex inserts (bits), such as Apex or another quality tool manufacturer, used with a 1/4" drive handle or a 3/8" impact wrench, should provide better results than a common L-shaped wrench. It doesn't surprise me that UPS can damage your equipment, they're really rough on package handling. The boxes that I've received by FedEx always look as though they've been handled carefully. WB .............. "Joe" wrote in message ... That's part of the problem. The plate needs to be real stiff so aliminum won't work. As it is, UPS Ground sometimes mangles them in shipment which always amazes me! As for the screw... I could try to find galv. screws but aluminum surely won't work. Black oxide seems the best answer for all intents and purposes... We need strength and most of the time, these things are there for the life of the machine which could be 5 years and 10 million holes... But if and when they need to be removed, they're a real headache. Not nearly as bad as if one came loose or broke though and destroyed belts, custom aluminum pulleys, guards, or worker's fingers! Really what I'm looking for is an allen key-type tool that won't degrade under stress like a full allen key will and/or one that I can apply either a shock to (impact or something) or lots of torque to remove the flat head. It's not a mjaor dilema, but I know how much everyone here loves to solve problems like this so I figured I'd ask and try to learn. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- |
On Wed, 12 Jan 2005 17:18:39 -0500, "Joe"
wrote: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. Regards, Joe Agro, Jr. How about adding a shim stock thickness steel washer to the screw and slightly increase the countersink depth to compensate. The washer would deform to fit the countersink and eliminate the contact with the galvanised surface. JIm |
You should be able to find allen/hex drivers for 1/4" and/or 3/8" drive
handles.. ratchet, T-handle etc. The adapters with replaceable inserts can usually withstand a sharp impact inline with the fastener, such as a rap with a hammer. Our last experiment was to buy genuine "allen" brand T-Handle units (they have a tough welded on metal "T" under all that rubber, cut the length of the allen key part down to about 2" and try rapping it with a hammer while turning gently with 12" extensions on the handle. Still twisted the key like a pretzel. SNIP It doesn't surprise me that UPS can damage your equipment, they're really rough on package handling. The boxes that I've received by FedEx always look as though they've been handled carefully. UPS treats us much better than FedEx ground does here in NJ IMHO. Guaranteed delivery times, lower cost and the FedEx guys basically deliver anytime they want from what I can tell. It is almost as if they wait for a number of deliveries in a certain area before they even bother to send a truck out with my stuff. The boxes generally do show up in better condition, but seeing as my customers pay the (insignificant) cost of shipping, we just went over to "overkill" packaging methods and stuck with UPS. -- Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
What size screws are these?
Joe wrote: You should be able to find allen/hex drivers for 1/4" and/or 3/8" drive handles.. ratchet, T-handle etc. The adapters with replaceable inserts can usually withstand a sharp impact inline with the fastener, such as a rap with a hammer. Our last experiment was to buy genuine "allen" brand T-Handle units (they have a tough welded on metal "T" under all that rubber, cut the length of the allen key part down to about 2" and try rapping it with a hammer while turning gently with 12" extensions on the handle. Still twisted the key like a pretzel. SNIP It doesn't surprise me that UPS can damage your equipment, they're really rough on package handling. The boxes that I've received by FedEx always look as though they've been handled carefully. UPS treats us much better than FedEx ground does here in NJ IMHO. Guaranteed delivery times, lower cost and the FedEx guys basically deliver anytime they want from what I can tell. It is almost as if they wait for a number of deliveries in a certain area before they even bother to send a truck out with my stuff. The boxes generally do show up in better condition, but seeing as my customers pay the (insignificant) cost of shipping, we just went over to "overkill" packaging methods and stuck with UPS. |
What size screws are these?
3/8-16. And I forgot, it's nickel plated, not galvanized. grin -- Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
I think this was mentioned, but it is worth thinking about , is the
plate thin enough that the taepred part of the screw is binding in the hole? Used to make 100 degree sheet metal screws for that. They might make undercut screws If the threads are rolled, it usually takes up the countersink at the top of the hole. MAybe try a big ass c sink[in the tapped part] to see if it solves it Otherwise never sieze seems to be the idea Joe wrote: What size screws are these? 3/8-16. And I forgot, it's nickel plated, not galvanized. grin |
I think this was mentioned, but it is worth thinking about , is the plate
thin enough that the taepred part of the screw is binding in the hole? Used to make 100 degree sheet metal screws for that. They might make undercut screws If the threads are rolled, it usually takes up the countersink at the top of the hole. MAybe try a big ass c sink[in the tapped part] to see if it solves it Nada. Doesn't make contact with the threads like that. Once the heads are drilled off to remove really stuck ones, we remove the screw thread part by hand. -- Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
On Wed, 12 Jan 2005 23:48:10 -0500, "Joe"
calmly ranted: CLIP Thirty years ago it was common in the motorcycle circle to remove flat head phillips screws from the aluminum casting with a tool called an 'impact driver' (IIRC). CLIP Excellent advice. I have both a motorcycle and have tried this. The hex head on the tool stripped right off on a stubborn one we wound up drilling. Oh, just drop a teensy drop of LOX on the head and wait a minute. It will have shrunk and warmed enough to release by then. ;) Maybe I'll take a digital photo of the allen key I use to tighten the flat heads tomorrow so everyone can see the pretzel-like "twist" it still maintains from the last removal project. Like my 90° Taiwanese (or was it Indian?) drill bit? No, that's not the angle of the cut, it's the shape of the drill rod after I tried to use it once. ================================================== ======== Save the ||| http://diversify.com Endangered SKEETS! ||| Web Application Programming ================================================== ======== |
On Wed, 12 Jan 2005 23:46:05 -0500, "Joe"
wrote: SNIP Make the galvanized plate from aluminum, big reduction in problem. Make the screw aluminum as well, problem gone (but you'll need to be sure that the aluminum plate and the aluminum screws are designed in sizes that will do the job, if that is possible.) That's part of the problem. The plate needs to be real stiff so aliminum won't work. As it is, UPS Ground sometimes mangles them in shipment which always amazes me! As for the screw... I could try to find galv. screws but aluminum surely won't work. Black oxide seems the best answer for all intents and purposes... We need strength and most of the time, these things are there for the life of the machine which could be 5 years and 10 million holes... But if and when they need to be removed, they're a real headache. Not nearly as bad as if one came loose or broke though and destroyed belts, custom aluminum pulleys, guards, or worker's fingers! Really what I'm looking for is an allen key-type tool that won't degrade under stress like a full allen key will and/or one that I can apply either a shock to (impact or something) or lots of torque to remove the flat head. It's not a mjaor dilema, but I know how much everyone here loves to solve problems like this so I figured I'd ask and try to learn. Regards, Joe Agro, Jr. Doesn't help you for the existing ones, but is possible to use a nylon, PE or PTFE washer under the heads of the screws in future. Its possible that merely using the thickness of a plastic bag would give enough insulation and lubrication to avoid the galling and bonding that you are seeing. Mark Rand RTFM |
On Thu, 13 Jan 2005 18:42:47 -0500, "Joe"
wrote: What size screws are these? 3/8-16. And I forgot, it's nickel plated, not galvanized. grin Can you try galvanized? the zinc acts as a passable lubricant. Mark Rand RTFM |
Like my 90° Taiwanese (or was it Indian?) drill bit? No, that's not
the angle of the cut, it's the shape of the drill rod after I tried to use it once. LOL. It amazes me theat the stuff that comes from these countries is either total junk or higher quality than we can get here. One problem is predicting which you will get if you break down and order them... -- Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
Can you try galvanized? the zinc acts as a passable lubricant.
The plate is nickel plated. The screws are hex head hardened grade 5 or 8 I think... Black oxide, right? anyhow... Strength is needed and I don't think they make glavanized or nickel coated hex heads in those grades. -- Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
On Thu, 13 Jan 2005 22:11:10 -0500, "Joe"
wrote: Can you try galvanized? the zinc acts as a passable lubricant. The plate is nickel plated. The screws are hex head hardened grade 5 or 8 I think... Black oxide, right? anyhow... Strength is needed and I don't think they make glavanized or nickel coated hex heads in those grades. Grade 5 electroplate will certainly be available, I'm less sure about Grade 8. It was a brain fart on my part :-( Mark Rand RTFM |
In article , news.ind.net.spamtrap1
@yunx.com says... Can you try galvanized? the zinc acts as a passable lubricant. The plate is nickel plated. The screws are hex head hardened grade 5 or 8 I think... Black oxide, right? anyhow... Strength is needed and I don't think they make glavanized or nickel coated hex heads in those grades. I thought these were hex socket flat heads? In inch sizes the standard alloy hex socket cap screws are a bit stronger than grade 8s. Zinc plated alloy hex socket flat heads are easily available. Ned Simmons |
Put a normal hex key in the screw and put as much pressure on it as you can with out permanently bending it. Start tapping the bend in the hex key with a hammer while applying pressure. Sometimes it takes a couple of minutes but it has always worked even on very rusty screws. Making a hex key with a better striking area would probably help but the repeatative impact makes a big difference. Cheers, Kelley On Wed, 12 Jan 2005 17:18:39 -0500, "Joe" wrote: We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. Regards, Joe Agro, Jr. http://www.autodrill.com http://www.multi-spindle-heads.com V8013 My eBay: http://tinyurl.com/4hpnc |
"Joe" wrote:
We use some decent flat head screws on our units and I've run into a strange problem. When we tighten them into the aluminum housings, they hold a galvanized plate in place. After about 10 minutes of being on there, they are almost impossible to get off. We have turned the highest quality allen keys we can find into pretzels and have stripped many using impact and a shorter length. Sometimes we have success by using a chisel to "spin" the flat head loose but that's the Neanderthal method I'd like to avoid... Even that fails 50% of the time. We can't use heat because there is a rubber seal in the aluminum very close. The flat head actually grabs onto the galv. plate so well that our customers (and us!) have to drill them out 8 out of 10 times we need to remove them... Anyone know of a super allen key or some other method of removing these that might work? We know that when we use painted plates, we have less of a problem and have considered painting the countersink of each flat head hole, but that's crazy in the big scheme of things... Thoughts, wisdom and random visits from friends welcome. You appear to have some sort of bonding process going on between the screw and the parent material. 1) Use TORX screws instead of allen screws. You can apply significantly more torque without rounding off the fastener or the tool. 2) Use antiseize or moly lubricant under the screw head. 3) Reduce the tightening torque. 4) Use an impact screwdriver to undo or give each screw a good belt on the head before trying to undo it. 5) Consider the electro-plating of the screws with respect to the parent material. A different finish might resolve the problem. -- Dave Baker - Puma Race Engines (www.pumaracing.co.uk) |
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