The S just HTF

[jumbopanda]

Ok, the S just HTF for me.

My tap broke off inside my AK trunion! Now before you laugh and tell me that I should have done a rivet build and whatnot, tell me something. Should I go get a special tap extractor or just let it be and go with two screws? The hole that the tap is stuck in is the middle hole, btw.

[Sydwaiz]

Where are you located? You can try finding a friendly machine shop with EDM machines. The easiest way would be with a carbide endmill. That's how I remove broken taps. I use my EDM as a last resort.

[jumbopanda]

End mills? Do you just feed them straight down into the hole? Isn't it hard to cut through taps?

[bu-bye]

A good end mill will cut through just about anything. The other thing you can do is weld it all up then re-drill it.

[NeoWeird]

If you are careful, and if it's not too deep, you can try to chip it out with a good prick punch. I had to do that, but I had only a TINY bit in, anything more than a 1/4" or so and I would not recommend it. Drilling is NOT an option. If you want to keep it cheap, you can always knock it out, redrill to a larger size, and retap. Carbide MIGHT work, but I've never tried using an endmill to get broken taps out (not saying it won't work, or that you shouldn't, I've just never done it). I'm by no means an expert either, so keep that in mind.

Have you tried to back it out a pair of needle nose pliers, two nails, etc? The taps used on AK builds are pretty thin and once they are under pressure if you put much lateral force on them they can sheer off right at the top of the AK metal, but they are not bogged down and jammed in tight. If you don't 'cut' it out, I'd try chipping it a tiny bit (be careful not to deform the metal it's in) and then back it out with something. I've even heard of takine a piece of wire and winding it up, then turning it and feeding it into the thread grooves, then when you get it in as deep as it goes you can pull on the wire fairly tight and it will grip the tap walls and help back it out.

If you do this, you might be able to use the existing cut threads and just get a new tap to finish (although expect a sloopy thread job, and you will probably have to go a size larger to get positive thread lock).

Good luck with that.

ETA: Keep in mind that taps are hardened steel, so you better use a good carbide endmill if you do go that way.

[jumbopanda]

Tried twisting it out, inserting nails into the flutes, and breaking it. None worked. I think I'll try the end mill method and drill larger. The hole is currently drilled for 10-24 screws, but I also have 1/4-20 screws on hand which would work just as well.

[metalhead357]

GO SLOWER next round, and use more oil. Use a lot more back out action than trying to cut full swaths. I know it can happen on just about anything but was your hole cut/drilled to the proper size before attempting to tap? ((ask me how I know this but no, thankfully, not on gun or gun parts)).........

Good luck

[NeoWeird]

That reminds me, the AK trunion seemed to make chips that did not want to break easily. As you turn into it, you will feel the chip build and then when you let off of it make sure you go back far enough to hear the chip break. Usually I only need to go back a quarter to half turn back to get it to break, but on the AK trunions it seemed to almost go a complete turn back before it would break towards the bottom. Might keep that in mind next time. Just because you feel the tap go free when you back off doesn't mean you broke the chip. Also there is nowhere for the chips to go, so maybe back the tap out 60% of the way down and blow it out before finishing. Wouldn't hurt next time.

[ZapThyCat]

Folks, lets not use the term "SHTF" for stupid issues. When SHTF happens people will be dying by the dozens or hundreds, that's far different than a broken part in a gun.....

[BigMac]

GO SLOWER next round, and use more oil.
Good luck

No, do not use oil. Use cutting fluid. This was the advice given me be a machinest that removed 3 taps for me.

I bought some stuff called Rapid Tap, in a little yellow lighter fluid looking can, at OSH and it works great.

[Charliegone]

My suggestion..get some cobalt drills (hard metal kind) and drill through it. Worked for me when a piece of drill got stuck on the rear trunion on my ak. Went right through. Also, do get cuttiing fluid. I got ace stuff which is pretty good. Plus...these drills will cut through metal like swiss cheese, so please be careful.

[saki302]

I busted out a tap by using a hardened punch and a medium weight hammer. A few whacks and little teeny pieces came out. And it was also in a trunion :P hahaha

-Dave

[DRH]

Spend the $20-25 bucks for a broken tap extractor and also buy a few spare sets of fingers at the same time. It makes easy work of getting the broken taps out.

http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=1737705&PMT4NO=14935705

http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=1737834&PMT4NO=14935705

[jumbopanda]

The reason it broke was because I kept turning it after it hit the bottom, not because I didn't back it out frequently enough or I went too fast.

I thought to myself "just a little more..." and then....ARGH!

[jumbopanda]

My suggestion..get some cobalt drills (hard metal kind) and drill through it. Worked for me when a piece of drill got stuck on the rear trunion on my ak. Went right through. Also, do get cuttiing fluid. I got ace stuff which is pretty good. Plus...these drills will cut through metal like swiss cheese, so please be careful.

The problem with using drills is that the surface of the broken tap is very uneven, which causes the bit to wander off center.


DRH, I've seen those, but why are there always ones that are less than $1 while another of the same size is ~$12?