Broken tap in blind hole

1980CJ7

1980CJ7

If it don't go, chrome it
Joined
Dec 10, 2006
Location
Leesville, NC
:poop:

Any ideas guys? ...any means of mechanical extraction is out of the question (there's nothing to grab hold of). At this point, I'm thinking EDM, or acid but I've never had to resort to something like that . In case it matters, that tap is a M4 and it's boken off inside a $1000 motorcycle crankshaft. :shaking:

...any experience or ideas ?
Steve
 
how deep down in the hole is it? I dont have any great ideas, unless it is flush with the top of the hole, and i would definitely try to weld a nut to it.

Edit: good luck, nothing worse than dealing with broken bolts/taps, especially in such an expensive part.
 
Take a small punch and just keep hitting it. It will eventually shatter. Had to have some help (thanks Larry) doing that on a manifold bolt hole in my Explorer after I bought the $120 set of tap extractors.
 
There is a welding rod designed just for that it used to be made by a company called x-trac alloy. It will weld to the stud and never hurt the threads, it was unbelieveable when I saw it demonstrated the flux would work in reverse and coat the threads and build on the stud. Then you could weld a nut to the tit and with the heat already present it would come right out. I haven't used one in a while but some specialty machine shops might be familiar with them." Corrective note", the company that made them was X-ERGON and the rod was x-trac aloy
 
I had this problem the other day I used a punch and taped it in the direction as if I was backing it out after about 20 min I got lucky came right out give it a shot who knows mabey it will work for u too
 
JRB said:
Take a small punch and just keep hitting it. It will eventually shatter. Had to have some help (thanks Larry) doing that on a manifold bolt hole in my Explorer after I bought the $120 set of tap extractors.
Click to expand...

Have done this before and it works

cgm147 said:
I had this problem the other day I used a punch and taped it in the direction as if I was backing it out after about 20 min I got lucky came right out give it a shot who knows mabey it will work for u too
Click to expand...

done this also
 
I run a machine shop. This happenes from time to time. Usually we can get them out with a carbide endmill on the machine (CNC). On a tap this small, I usually send it to:

Wirtz Wire , he's in Hendersonville, he can burn it out with out damaging the hole.. Usually cost me around $30. Not bad price and a lot safer than hammer and punch.

His number is 828 696-0830, ask for Patrick.
 
mbrooks said:
I run a machine shop. This happenes from time to time. Usually we can get them out with a carbide endmill on the machine (CNC). On a tap this small, I usually send it to:
Wirtz Wire , he's in Hendersonville, he can burn it out with out damaging the hole.. Usually cost me around $30. Not bad price and a lot safer than hammer and punch.
His number is 828 696-0830, ask for Patrick.
Click to expand...


thats what i would do my self on one that small.
 
Thanks for all the feedback yall, there's a place up in Wake Forest (Superior)where I can take it , they said they can burn it out with their EDM machine for between 50 and 100 bucks I guess everthing is more expensive in Wake County :shaking:
 
had a guy bring in a dana 60 nuckle the other day with a broken stud in the kingpin with a easy out broke off in it. we used a masonary bit that we sharpened in a drill press. i couldnt believe how easy it drilled the extractor out. the trick is to run the press as fast as it will go and keep the bit lubed.
 
91oneton said:
had a guy bring in a dana 60 nuckle the other day with a broken stud in the kingpin with a easy out broke off in it. we used a masonary bit that we sharpened in a drill press. i couldnt believe how easy it drilled the extractor out. the trick is to run the press as fast as it will go and keep the bit lubed.
Click to expand...

got to be a carbide tiped bit. also carbide does not like an interupted cut (brittle & chips easlily) so keep a load on it. carbide will take the heat though, so high speeds will work. Most times the higher speed will cut before the piece work hardens.
 
liquid nitrogen will make the metal contract. you can get the liquid nitrogen from those compressed air cans. use it upside down, and don't let it get on your skin. heat up the outside of the shaft a little. then try to drill out the bolt with a left handed drill bit. it worked for me
 
Back
Top