# Broken tap woes



## Scythe_rr (May 3, 2006)

Does anybody have any ideas as to how to get the blasted thing out, it's an M4 plug tap in a 10(ish)mm deep hole in mild steel, and the end is about 1/2mm down in the hole.
I've tried everything i can think of but it's too damn small to get a propper grip on.


Please help


----------



## cmacclel (May 3, 2006)

You can *Try* a cobalt drill........good luck. Broken Taps are the worst.


Mac


----------



## TinderBox (UK) (May 3, 2006)

would it be possible to heat the steel so that it expands a little.

you might loosen the tap enough to be able to turn it with somthing down the swalf slots.

regards.


----------



## mahoney (May 3, 2006)

Go to a local machinists supply house (or find a good online source). Buy a broken tap extractor. You will need to know the size of your tap and how many flutes it has. These have a solid body with sliding "fingers" that go down into the hole and fit in the flutes of the broken piece of tap. If you can find one the right size, this is a pretty slick and painless way to remove a broken tap.


----------



## Scythe_rr (May 3, 2006)

yeah, i tried doing that with circlip pliers but with no sucsess. I once got a friend's out using that method with needle nose pliers, but that was m16.


----------



## Scythe_rr (May 3, 2006)

cheers for the help anyway


----------



## Rothrandir (May 3, 2006)

how important is the part?

sometimes at work when someone breaks a tap into an expensive part, we burn it out. beyond your equipment i'm sure, but maybe a local machine shop could help you out?


----------



## tvodrd (May 3, 2006)

What Roth said! There are various extractors out there, but they have rarely worked for me. They also make "special" carbide drills for drilling them out. They're difficult to get centered as the tap rarely breaks "square." I have had to go to Jerry's broken tap and drill with my tail between my legs more than once over the years. The EDM guys can make fairly quick work of it but will probably cost you $35 or so. Good luck!

Larry


----------



## Morelite (May 3, 2006)

Try using a reverse (left hand thread) drill bit while appling heat to the surrounding area.


----------



## gadget_lover (May 4, 2006)

What about the idea of re-drilling the hole a bit bigger and starting over? I know the tap will be a hassle to drill through, but just a thought.

Daniel


----------



## scott.cr (May 4, 2006)

If you decide to drill it out, and your workpiece isn't heat treated, you can use a propane torch to anneal the tap piece (heat it until red, let cool slowly).

If you live near an EDM shop it might only be a matter of a six-pack and a humble attitude to get them to burn it out for ya. ;-)


----------



## Turbo_E (May 8, 2006)

not sure how small your broken tap is, but what i usually do IF the end is near the hole surface is:

take a sharp hardened punch. and with a hammer, drive the busted tap in reverse. the puch usually digs into the tap and it should come out fairly easily as the threads are already cut. wd-40 may help as well as heat (not at same time)


----------



## highorder (Jun 3, 2006)

mahoney said:


> Go to a local machinists supply house (or find a good online source). Buy a broken tap extractor. You will need to know the size of your tap and how many flutes it has. These have a solid body with sliding "fingers" that go down into the hole and fit in the flutes of the broken piece of tap. If you can find one the right size, this is a pretty slick and painless way to remove a broken tap.



a huge +1


----------



## Luna (Jun 3, 2006)

Scythe_rr said:


> Does anybody have any ideas as to how to get the blasted thing out, it's an M4 plug tap in a 10(ish)mm deep hole in mild steel, and the end is about 1/2mm down in the hole.
> I've tried everything i can think of but it's too damn small to get a propper grip on.
> 
> 
> Please help



They make special electrodes for stick welders just for this. You put a nut on the top. The flux on the rod protects the threads and you basically run a verical bead that you weld to the nut. Now you just treat it like a bolt

If you have a mig, you can probably do the same thing since the top of the tap is almost outside the hole. 

Good luck


----------

