Broken Tap Removal

[rmcshane]

Today I was cleaning up the threads in a Kohler engine I am rebuilding. Everything was going well, had the tap greased up like the rear-end of a sick cow. Got to the third hole and the tap snaps off about half way in the hole. It was going in kind of hard, but not anything out of the ordinary. Its a fairly clean break, its a 4 fluke tap. I've never had any experience removing a broken TAP before, more removing broken head bolts and such. Any advice out there besides going to the machine shop? I know taps are very hard and require special tools to remove them...is there any tool out there that is affordable that will successfully remove them? Thanks for any advice/help.

 

[mfrade]

Maybe try the ol' hammer & punch to back it out?.. Once it starts turning it should come out easily.

Being very hard taps are brittle. I've smacked'em with a hammer and punch and broken it into pieces, then dig out the pieces.

Or, get a old bit, grind the point backwards and use a reversible drill motor, hopefully it'll snag on the bit and pull the tap out.

Lastly, carbide drills and take your time. get a hole through it and use a easy-out.

I've used all these ways to dig out broken taps. Check your taps for damage after each use, toss any tap with broken teeth or wear / damage.

 

[bkiper]

The last time this happened to me I made an extractor to remove them. First find a bolt the next size down. Then on the theraded end drill a small hole up through the bolt around the same size as the center of the tap. next take a die grinder with a cut off wheel and make two deep cuts perpendicular to each other. stick the bolt in the hole with the broken tap and back it out. I have made several of these in various sizes and keep them in my box

 

[dcalkins]

Ryan ,first never use oil or greese in cast iron ,you may be able to rent a tap extractor ,or take it to a machine shop ,the block cost too much to mess with ,good luck .David