dsavitsk 4,440 Posted October 5, 2011 Report Share Posted October 5, 2011 Maybe keeping such things in one place will prove helpful? Maybe not. Anyway, to get the ball rolling, does anyone have a technique for removing a snapped off 4-40 tap from extruded aluminum side rails? Maybe the sort of kit one uses for removing stripped screws would work, but there is no head, essentially. Any other thoughts? Quote Link to post Share on other sites
CherryBomb 14 Posted October 5, 2011 Report Share Posted October 5, 2011 Maybe keeping such things in one place will prove helpful? Maybe not. Anyway, to get the ball rolling, does anyone have a technique for removing a snapped off 4-40 tap from extruded aluminum side rails? Maybe the sort of kit one uses for removing stripped screws would work, but there is no head, essentially. Any other thoughts? If I am understanding you correctly, you have a broken tap trapped in aluminum and need to remove it. In the past what I have done is to use a very small drill bit to drill a small hole into the trapped tap. Then I use a broken bolt kit to remove. Been years since I have done this, so, there may be better ways of doing it now. Quote Link to post Share on other sites
vvs_75 11 Posted October 5, 2011 Report Share Posted October 5, 2011 Try to drill a small hole in to broken tap and then push hard with a star screwdriver that just a bit larger than the hole and try to unscrew it, It works on screws. Quote Link to post Share on other sites
kevin gilmore 1,454 Posted October 5, 2011 Report Share Posted October 5, 2011 Without a precision mill, and some carbide bits, this is next to impossible. Taps are very hard and very brittle. If you have access to an ultrasonic cell disruptor, those have been known to loosen broken tap bits. Quote Link to post Share on other sites
morphsci 5,811 Posted October 5, 2011 Report Share Posted October 5, 2011 ... this is next to impossible. .... Which is like mostly dead. Quote Link to post Share on other sites
dsavitsk 4,440 Posted October 5, 2011 Author Report Share Posted October 5, 2011 If you have access to an ultrasonic cell disruptor, Unfortunately, I don't know any Romulans, Klingons, or Cardassians from whom to borrow a disruptor. I do have the sense this is a lost cause as it is pretty tiny, and as you say, quite brittle. Note to self, tap cases before having them machined, rather than after And, replace taps when they seem like they might be worn rather than trying to eek out one more case. Quote Link to post Share on other sites
Voltron 25,075 Posted October 5, 2011 Report Share Posted October 5, 2011 (edited) Which is like mostly dead. Edited October 5, 2011 by Voltron Quote Link to post Share on other sites
luvdunhill 3,266 Posted October 5, 2011 Report Share Posted October 5, 2011 I could cut the case down for you Quote Link to post Share on other sites
The Monkey 764 Posted October 5, 2011 Report Share Posted October 5, 2011 I like this thread. I wish I could do casework like some of you magicians. Maybe I'll learn something to help my meager skills. Quote Link to post Share on other sites
wink 364 Posted October 5, 2011 Report Share Posted October 5, 2011 I once had success with needle-nose pliers and worried the tap out, but the tap size was larger.. Quote Link to post Share on other sites
dsavitsk 4,440 Posted October 5, 2011 Author Report Share Posted October 5, 2011 Maybe I'll learn something to help my meager skills. Best thing I've learned is to farm out casework to professionals whenever I can I once had success with needle-nose pliers and worried the tap out, but the tap size was larger.. It is broken pretty flush to the case. But, there is a little wiggle, and the tap tip is fluted, so I may be able to stick some thin metal bits down these channels and turn it just enough to expose enough to grab with some small pliers. Maybe some vibration would cause it to extract itself? I could put it on a UPS truck for an afternoon. Quote Link to post Share on other sites
Pars 1,596 Posted October 6, 2011 Report Share Posted October 6, 2011 Putting it on a UPS truck, it would likely return with far more pressing problems than a broken tap... A 4-40 tap would be pretty small to try to drill into, and as Kevin noted, hard and brittle. If you have some really sharp pointed tweezers, maybe try to work it around to loosen it enough so there is something to grab onto? Good luck! And good thread idea as well. Quote Link to post Share on other sites
kevin gilmore 1,454 Posted October 6, 2011 Report Share Posted October 6, 2011 The cell disruptor is not a joke. I have a 600 watt one. Nasty device. Reminds me of the dentist. In the future don't tap holes by hand without a jig that holds the tap absolutely straight. Then they don't crack off. Quote Link to post Share on other sites
samuel 0 Posted October 6, 2011 Report Share Posted October 6, 2011 There are a lot of different techniques you can find by googling. This situation happened to me once, and I succeded using a technique that surprisingly I cant' find anywhere: I put a very small amount of loctite on the top of a flat barrel of a diameter slightly smaller that the tap, and carefully introduce it into the hole until it makes contact with the broken tap. Then I wait 2 min while maintaining the pressure to make sure the two are glued. Then I unscrew gently...voilà . Problem is you can glue everything together, and then you are screwed, but if you are careful enough, and have a steady hand, it should work. Quote Link to post Share on other sites
wink 364 Posted October 7, 2011 Report Share Posted October 7, 2011 One of the problems with tapping holes is the methodology. I usually turn the tap about 1 turn then retract half a turn to break the swarf. If you don't do this usually the tap gets stuck on the hole and sometimes breaks in the attempt to extract it. Some tips:- http://www.spaco.org/taptips.htm Quote Link to post Share on other sites
livewire 52 Posted October 7, 2011 Report Share Posted October 7, 2011 True that Wink. Them tap-tips got it covered! Quote Link to post Share on other sites
FrankCooter 28 Posted October 7, 2011 Report Share Posted October 7, 2011 I've been thinking about getting into DIY powder coating. The professional metal finishers around here want ridiculous prices for small jobs. Looks like you can get started for about $300. Anyone have any experience in this area? I think this thread is a good idea. Half the reason I build stuff is the craft, creativity, and artistic expression that goes into i the casework. Quote Link to post Share on other sites
swt61 10,094 Posted October 7, 2011 Report Share Posted October 7, 2011 I've heard good things about the Eastwood powder coating kit. You'll definitely want to purchase a separate oven for this, as the oven can no longer be used for food after powder coating. The good thing is that used ovens with burnt out stove top elements are usually had pretty cheap. Quote Link to post Share on other sites
guzziguy 1,776 Posted October 7, 2011 Report Share Posted October 7, 2011 Let me know if you need help moving an oven, Frank. Quote Link to post Share on other sites
luvdunhill 3,266 Posted October 7, 2011 Report Share Posted October 7, 2011 I have access to the Harbor Freight oven and kit. Haven't used it, but people say it isn't total crap. Prices around here are decent to get it done professionally, as long as you aren't picky about options and timeframe. Quote Link to post Share on other sites
Milosz 13 Posted November 12, 2011 Report Share Posted November 12, 2011 you could try to weld something onto the tap and use that to extract it. But you might just end up kind of arc welding the tap into the hole.... if you can get any sort of grip on the tap, you can try heating the aluminum to a few hundred degrees in your home oven and then dripping some freeze-mist on the tap (or butane, or "Canned Air" CFC liquid- be careful with any flammables) That might make it possible to remove it.... The other possibility is to carve out the aluminum around the tap with a small Dremel tip, then grab the tap. You'll have to fill in the hole you carved out.... can be done in various ways, including inert gas welding....... Quote Link to post Share on other sites
eggil 80 Posted March 6, 2012 Report Share Posted March 6, 2012 (edited) Any ideas on how to install a recessed toggle switch like this one? Edited March 6, 2012 by eggil Quote Link to post Share on other sites
ujamerstand 19 Posted March 6, 2012 Report Share Posted March 6, 2012 That's a thick front panel. So you blind tap a few holes at the back of that thing, and mount a second thinner plate on it. Then use the second plate to mount the switch. Quote Link to post Share on other sites
swt61 10,094 Posted March 6, 2012 Report Share Posted March 6, 2012 Yep, that's how i'd do it too. Nice knobs! Quote Link to post Share on other sites
n_maher 11,580 Posted March 6, 2012 Report Share Posted March 6, 2012 That's a thick front panel. So you blind tap a few holes at the back of that thing, and mount a second thinner plate on it. Then use the second plate to mount the switch. You could still mount the switch directly to the front panel with the blind tapped holes, you wouldn't necessarily need the second plate. Quote Link to post Share on other sites
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