sparky mike | 24/10/2020 08:02:58 |
259 forum posts 77 photos | I have to remove a dozen Phillips head self tappers from rusty steel plate and each one has rusted in tight. Nothing will shift them and can't use heat as they are next to fiberglass.I need to remove the heads so I can remove a chrome trim piece that is unobtainable, so must not damage it. Where can I buy decent diamond drills from ? The Chinese ones last two minutes and then go blunt, so no go there. Mike. |
Mike Poole | 24/10/2020 08:18:40 |
![]() 3676 forum posts 82 photos | If you have a steady hand could you slot them with a Dremel disc for a screwdriver? They will probably shear off with a decent screwdriver. A carbide drill will be hard enough to drill the heads but chipping the edge may be a problem. I am guessing the job doesn’t have the mass to allow an impact driver to be effective. Mike |
Tony Pratt 1 | 24/10/2020 08:33:29 |
2319 forum posts 13 photos | Mike has listed the 2 methods I would try. Tony |
sparky mike | 24/10/2020 08:48:12 |
259 forum posts 77 photos | No Good, a Dremel disc would damage the chrome brass strip that is held on with the screws as screws are countersunk. Mike. |
Tony Pratt 1 | 24/10/2020 08:53:28 |
2319 forum posts 13 photos | You can buy left handed twist drill, I've had success with them. Tony
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sparky mike | 24/10/2020 09:00:03 |
259 forum posts 77 photos | Any normal good quality twist drills will not touch these screws. They are well hardened. All I want to know is where to buy decent diamond drills. Have tried all the obvious methods. Mike. |
Speedy Builder5 | 24/10/2020 09:09:50 |
2878 forum posts 248 photos | I see that amazon.com is selling US made "quality" diamond drills - packets of 10. for about 20 dollars. |
John Haine | 24/10/2020 09:28:42 |
5563 forum posts 322 photos | It might be worth trying a Heller cobalt drill? |
pgk pgk | 24/10/2020 09:30:59 |
2661 forum posts 294 photos | No experience with them but: here It'd also be another situation where a high speed dental handpiece with coolant and enough patience to paint away the head of the screws. Dental burs are cheap. Back when i was working I used to make hip toggles out of scrap intramedullary pins, eyeballed, using my dental kit. Cheap handpieces are just that but work well and can be adapted to a shed compressor.
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David George 1 | 24/10/2020 10:01:21 |
![]() 2110 forum posts 565 photos | You can buy special carbide drills they can drill HSS taps so screws should be no problem. https://www.drill-service.co.uk/products/drills/spade-and-tap-removing-drill/dctrd-carbide-drill-tap-removing-spade-type/# David |
Michael Gilligan | 24/10/2020 10:24:43 |
![]() 23121 forum posts 1360 photos | Posted by sparky mike on 24/10/2020 09:00:03:
[…] All I want to know is where to buy decent diamond drills. Have tried all the obvious methods.
. https://www.eternaltools.com/drill-bits MichaelG. |
david homer | 24/10/2020 10:52:49 |
43 forum posts | After seeing this post I caught sight of this add on you tube, not sure if these are any use but are made for the application you need, hope the link works .georgeshop.co.uk/products/mintiml™-screw-extractor4-pcs?variant=32927540707363&gclid=EAIaIQobChMIr5zLofnM7AIVyt3VCh2w0ggiEAEYASAAEgKIw_D_BwE
David |
Andy_G | 24/10/2020 11:15:05 |
![]() 260 forum posts | When I did some work with diamond tooling years ago, machining steel was an absolute no-no (it reacts with the diamond under very high pressures, IIRC). CBN was needed for ferrous metals. UK drills do tungsten carbide tipped drills which might be a better bet if cobalt ones don't work.
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Les Jones 1 | 24/10/2020 11:46:32 |
2292 forum posts 159 photos | If you know someone with a small EDM (Electrical discharge machine.) that would probably work. Les. Edited By Les Jones 1 on 24/10/2020 11:46:54 |
peak4 | 24/10/2020 13:14:41 |
![]() 2207 forum posts 210 photos | Sparky, Sorry if this is a long post, when you've only asked where to buy diamond bits. I assume Philips or Posidrive heads, where a normal screwdriver cams out and damages the slots. Good luck
Edited By peak4 on 24/10/2020 13:18:09 |
Jeff Dayman | 24/10/2020 14:25:07 |
2356 forum posts 47 photos | When I am faced with this sort of screw removal issue from parts that must not be damaged I use my home-shop-built EDM (the Ben Fleming design mk1 with mods) and a hex brass or milled copper hex electrode. This burns a hex pocket in the screw and a hex key in the new pocket plus penetrating oil usually gets them out without any fuss. Since EDM is a zero force cutting technology, if the electrode is placed carefully over the work , the ram holding the electrode drive is fixed in place, and depth of cut is checked frequently there is almost no risk of damaging adjacent parts. My EDM machine was simple to make, not too expensive, and has paid for itself many times over by handling repairs and screw / broken tool removals hard to do by any other method. |
Nick Wheeler | 24/10/2020 15:03:53 |
1227 forum posts 101 photos | An important thing to consider when working with cross-head screws is that the screwdriver you're going to use on them is a consumable! It needs to be the right type(Phillips, Pozi and JIS are not the same) and in good condition. Even a slightly chewed tip will ruin perfectly good screws. Any driver in this condition should be taken to the grinder and turned into a pick/awl/scraper/general poky tool, or you'll put it back in the box and bugger up more screws in the future.
If possible, use an impact driver from the start.
You can buy specific grip paste for use on screws, but fine grinding paste works almost as well.
Sometimes grinding a slot across the head gives enough grip to undo the screw.
Once it's rounded out, drilling is necessary.
Anyone who has worked on aircraft will have their favourite methods for removing small cross-head screws because planes are littered with the bloody things; it takes a day to remove all the inspection panels on an Islander.... |
sparky mike | 24/10/2020 16:25:27 |
259 forum posts 77 photos | Thanks for all posts, the last three or four most interesting. I have a spot welder and considered using that to soften the screw steel but can't get to the back of this trim for the other electrode. The item I am trying to remove is the cant rail (gutter rail) from a classic car and its made of unobtainium. I have ordered some cobalt drills so will see what they do. I only need to remove the heads and then can remove rail and then I can attack what is left of the screw if not flush with the surface. The cant rails are going to be re chromed anyway so the slight scratch here and then is not too much of a problem. Mike. |
Phil P | 24/10/2020 16:47:44 |
851 forum posts 206 photos | I know this is a bit of the wall but if the screws are steel and the strip is brass, could you dissolve the screws out with Alum ? Its a bit akin to removing a broken tap. https://www.tap-die.com/contents/en-uk/d296_Tip_Remove_Broken_Tap_Drill_Reamer_Tap_and_Die_Co.html Phil Edited By Phil P on 24/10/2020 16:50:35 |
Steviegtr | 26/10/2020 16:36:38 |
![]() 2668 forum posts 352 photos | Did you get the screws removed. I just saw this ad for a screw removal kit. Looks pretty good. Steve. |
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