Broke a tap trying to bore bigger screw holes for my '89 GW wheel center caps

[Pasta_Man]

Hi all,
After losing a 2nd center cap, I decided I'd bore bigger screw holes in one of my '89 GW's wheels. I got a 10-32 tap and did a great job on one of the holes. Then I went to the next hole, and about 5 seconds from completing the job...the damn tap broke.

I've researched different ways of dealing with this, but I'd like to get your recommendations.

Thank you.
-Kevin

[SJTD]

I assume the break is below the surface???

There are tap extractors that fit down the flutes. Probably expensive and might not do it.

Maybe use a punch to break up the tap but it will probably damage the hole too.

Reclock the cap and make new holes?

[KillyMcGee]

Bought a tap just for the same purpose not long ago.

Did you drill out your holes 1st or just use the tap to enlarge them?

[Pasta_Man]

> Reclock the cap and make new holes?
Sounds like a good idea.


For the first hole, I just threaded the tap into the hole without drilling first. It worked fine, and was pretty easy.

For the second hole, the tap wouldn't easily thread (it looked like the tap threads may have gotten a bit damaged from the first hole, but I'm not sure) - so I drilled into that hole and then used the tap. Was smooth sailing until the tap broke off...

[wiley-moeracing]

Did you use tap oil also?

[Pasta_Man]

No tap oil. Need to follow instructions better next time...