broken tap

[rocketbob]

It it didn't shatter (which they do, even in aluminum) then since its likely a two flute tap at least 50% of the threads remain which would hold a screw just fine, especially considering the light load of the canopy glass.

[Azemon]

I have been a machinist for over 25 years and would indeed try to use a tap extractor first. But it must be done very carefully. I own and have used several
times a Hansvedt EDM or Spark Eroder. They are absolutely the best way to
remove broken taps as they do not damage the treads. Good luck.

Andy Jones

[LeeM_2000]

I had to have a broken tap removed from a motorcycle cylinder head a couple of years ago. The EDM worked very well. After that experience, I wouldn't even mess with trying to remove it myself. Now, I would just take it to a machine shop that has an EDM.