Broken tap, tapping for ace folding mechanism

[45pro]

OK so yeah...my tap broke while i was tapping to install my ace folding mechanism. I went and got a extractor with reverse threads, but that thing is a joke. you need to drill a pilot hole for it to work. How can you drill a pilot hole when the tap is stronger and the drill bit?!?

Does anyone know of a gunsmith or a machine shop that would remove the tap for me? i've read that a machine shop has a EDM (electro-discharge machine) that will take it out. Only problem is i dont know if they will work on a firearm. Anyone with any kind of experience that could help out would be appreciated.

i got the first one drilled and tapped for the screw. if all else fails could i just use the one screw and just tac weld the other side? Its never coming off again so i dont see why it would be a problem, however i would like to do it the right way if its still possible.

Help me please!!

 

[ar15junkie]

I would help if you could provide a picture of the broken tap and let us know what kind of firearm you are working on.

 

[william]

I broke a 1/4" tap off in an engine block once. I took it to a body shop and a guy there TIG welded a bolt to it and it backed out. Not sure how small the tap is you broke but a good TIG guy can weld pretty small.

 

[Mr.JAG]

I broke a tap off in my AK while tapping for a bullet guide. It took me 3 days to get it out (it was fast, once I figured out the trick).

Easy-outs to not work. Specialty tap extractors do not work if the tap is small.

Is the tap currently broken off in a hole that is all the way through? Read, the pilot hole is open at the bottom, not closed.

If so, here is what worked for me. Heat the area up is possible, then quickly unload a can of computer duster on it. Make sure to hold the duster upside down so it just spews the liquid nitrogen on it. Taps are made of a very brittle metal, the heating and then quickly cooling of the tap metal causes micro fractures in it. Just after you hit the tap with nitrogen from the duster, give it a few good smacks with a hardened punch. Don't wussy it if you don't have to. It might take a few tries, but the tap will eventually shatter.

Mine shattered like glass at around the 3rd heat/cool/whack go around.

 

[2cool9031]

If it is possible, just drill a new hole in the folding mechanism, close to the existing hole and then drill and tap a new hole for the screw, being careful not to break another tap. It is possible to drill a tap but you have to use a carbide drill. If you don't have a solid set-up you will just break the carbide drill...a hand held drill is not good enough. I have broken many taps in my time, and sometimes if they are big enough...you can break them out with a small punch and then just remove each little piece at a time.

 

[45pro]

I broke a tap off in my AK while tapping for a bullet guide. It took me 3 days to get it out (it was fast, once I figured out the trick).

Easy-outs to not work. Specialty tap extractors do not work if the tap is small.

Is the tap currently broken off in a hole that is all the way through? Read, the pilot hole is open at the bottom, not closed.

If so, here is what worked for me. Heat the area up is possible, then quickly unload a can of computer duster on it. Make sure to hold the duster upside down so it just spews the liquid nitrogen on it. Taps are made of a very brittle metal, the heating and then quickly cooling of the tap metal causes micro fractures in it. Just after you hit the tap with nitrogen from the duster, give it a few good smacks with a hardened punch. Don't wussy it if you don't have to. It might take a few tries, but the tap will eventually shatter.

Mine shattered like glass at around the 3rd heat/cool/whack go around.

its a 10-32 thread tap. The hole is all the way through. I'm not sure how i would heat up the area? i tried using a punch and just hamering it through or trying to break it and it just flattened the end of my punch. i dont have acess to a drill press so drilling it out isn't a option. i'm really about ready to just weld the mother f'er on there. the other side is drilled and tapped with no problems.

This is actually the 2nd hole i've drilled on the right side and i've broken a tap off in both of them. I dont understand because the first hole went fine.

i will try your method of heating up and cooling but im not sure what i can use to heat it up without discoloring the metal and making it look worse...

 

[45pro]

I broke a 1/4" tap off in an engine block once. I took it to a body shop and a guy there TIG welded a bolt to it and it backed out. Not sure how small the tap is you broke but a good TIG guy can weld pretty small.

I've read about this also, my only concern is that the tap is only about 3/16 in wide and i dont know if anyone at a machine shop will work on a gun. The only machine shop i know of around here is Napas shop.

 

[Mr.JAG]

Before you risk any heat damage... just try the cooling a few times.

It possible the tap will weaken enough to break by just getting it cold enough. Turning over a can of computer duster can get things surprisingly cold. Just make sure to go slow, you want the liquid and not the air.

 

[2cool9031]

Drilling a hole with a hand drill and tapping it is a crap shoot at best. The tap must be inserted in line with the hole. I would suggest to keep sharpening your punch, and keep at it. It's not going to work on your first try. You said it is a through hole it should be possible. Keep in mind, that even if you manage to pound the tap out there may still be some small pieces loged in the threads, so be extra careful when trying to retap the hole. If you don't have a grinder, to resharpen the punch, then you are sunk there.
One other thought...if the 2 tapped holes are opposite eachother, then insert a small pin type punch from the other side and try punching it out in the opposite direction.

 

[45pro]

Drilling a hole with a hand drill and tapping it is a crap shoot at best. The tap must be inserted in line with the hole. I would suggest to keep sharpening your punch, and keep at it. It's not going to work on your first try. You said it is a through hole it should be possible. Keep in mind, that even if you manage to pound the tap out there may still be some small pieces loged in the threads, so be extra careful when trying to retap the hole. If you don't have a grinder, to resharpen the punch, then you are sunk there.
One other thought...if the 2 tapped holes are opposite eachother, then insert a small pin type punch from the other side and try punching it out in the opposite direction.

worked good for the first hole. the 2 second ones......not so much....

The hole is all the way through but theres another piece of metal about a 1/4 in behind it so i cant punch it though, i was just hoping to break it in little pieces. I also cant punch it out from the other side because of the other metal piece.

 

[Chippp1961]

Try one of the automatic center punches. I have busted a lot of broken taps with them,and they do not distort the surrounding metal because it is more of a SHOCK than an impact.It takes patience tho,once it starts to break up pick the small pieces out.Sometimes it takes 30-40 times to break up a tap.
Good Luck
Chip

 

[XtremeVel]

OK so yeah...my tap broke while i was tapping to install my ace folding mechanism. I went and got a extractor with reverse threads, but that thing is a joke. you need to drill a pilot hole for it to work. How can you drill a pilot hole when the tap is stronger and the drill bit?!?

Does anyone know of a gunsmith or a machine shop that would remove the tap for me? i've read that a machine shop has a EDM (electro-discharge machine) that will take it out. Only problem is i dont know if they will work on a firearm. Anyone with any kind of experience that could help out would be appreciated.

i got the first one drilled and tapped for the screw. if all else fails could i just use the one screw and just tac weld the other side? Its never coming off again so i dont see why it would be a problem, however i would like to do it the right way if its still possible.

Help me please!!

A easy out will be worthless on that small and brittle tap. I have had a little success with them but only on case hardened larger machine screws.

All the EDM's we have use the most sticky oil for flushing. You would have more time dealing with the clean up than just trying to break it up like others have suggested. Now, if there are some EDM's out there that flush with something different, I don't know. Just remember the EDM would take the minor diameter out. You willl still have to remove the remainder if tapping the same hole.

If using a unguided hand drill, I would say you got lucky on the first. If you do get it out and try to tap the same hole, try using a "T" handled hand tool. Take it slow. Cut a thread or two, then back it out to clear the chips before continuing.

 

[Mr. Habib]

Try a left hand drill bit, that's what our machine shop does. As the drill is trying to dig into the tap, it is also turning it out. Work almost every time.

 

[2ADMNLOVER]

The hole is all the way through but theres another piece of metal about a 1/4 in behind it so i cant punch it though, i was just hoping to break it in little pieces.

I assume your working on your Draco ?

Have you considered just drilling out the tap then drilling the holes you need and using machine screws and lock tight ?

The problems your having are exactly the reason I HATE taps .

 

[45pro]

I assume your working on your Draco ?

Have you considered just drilling out the tap then drilling the holes you need and using machine screws and lock tight ?

The problems your having are exactly the reason I HATE taps .

Yes i'm working on my draco

Let me know when you find a drill bit that will drill and a hardened steel tap using using only a battery screw gun....

 

[45pro]

Try a left hand drill bit, that's what our machine shop does. As the drill is trying to dig into the tap, it is also turning it out. Work almost every time.

I'll give it a shot...

 

[45pro]

ok guys i couldn't get it out so i moved the mechanism down just a tad so i could redrill and tap new holes. IT WORKED!! and you cant see the old holes, they are hidden by the mechanism. I've posted pictures in the draco thread.