Why do you think that you cannot get someone to weld it? I have taken
stuff to shops to get fixed. Car doors, aluminum lawn mower decks,
aluminum heads and other stuff. I certainly would not trust someting
spinning at 4000 rpms to some glue when it was not manufactured that
way. Heat is not the issue. Vibration shaking the glue is. On the
other hand airplanes are assembled with glue. Remember the glued on
tail section that fell off the airplane in the past 10 years. Plane
crashed with no tail section. Of course there were hundreds of the
same model flying successfully, just one bad glue job.

"Bob" wrote:

I bought a "railroad" grinder off of ebay to grind my chisels and plane
irons. Its super heavy and very well made. I opened it up to check the
gears and grease them. I was not prepared for the weight of the outer casing
when I pulled it off and dropped it on the concrete floor - you guessed it.
It broke off the most critical part of the casting - the part where the
shaft for the grinding wheel goes through. Its only one half. The other half
is intact.

I was wondering if there is some form of epoxy that could be used to repair
the casting. I don't think I'll have much luck chasing down a welding shop
for this small job. Since its hand held and there is not much heat
generated, I don't think it will take a lot of strength to hold it together.

Bob