Sunday, May 29, 2011

What Were These Set Screws Made Of?

I had to replace the handwheel on the tailstock of my lathe recently--the head of set screw that holds the wheel to the shaft was no longer hexagonal, and I could not lock it down.  I ordered up a replacement handwheel from Sherline, and scavenged an equivalent set screw from the handwheel from Z-axis of the old vertical mill assembly. 

I hate to throw anything away, so I decided that I was going to remove the set screw from the old handwheel and replace it.  So I tried to use a screw extractor--but I could not drill a hole into the set screw.  I tried a .125" drill bill--no luck.  Sometimes it helps to use a small drill bit to get at least a small hole, then then larger drill bit can get some purchase.  No luck--and the 5/64" drill bit broke.  Then the .125" drill bit broke, even though I was flooding the area with oil to make sure that I was not overheating it.

What in the heck is this set screw made of?  Anyway, I gave up.  It was $18 to replace it, and there comes a point where you can't let the desire to save $18 waste hours of time.  It makes more sense to be writing articles.


  1. Try a dremel tool and no pressure let the machine speed do the work. You may have been pushing to hard and dulled then broke the bits. Also, maybe use a small punch to start the hole in the possibly hardened machine screw.

  2. Don't push on motor drill, it only dulls the bit. Try a dremel tool and let the speed of the motor do the work.ey