Patching a grinding wheel.

[Highpower]

I got another stone for my grinder and when I opened the box I see it had chips broken out on both sides of the bore. It would most likely have been fine to use as-is, but all I could think about was bumping into the drive shaft when changing wheels and chipping it out further. Just trying to nip it in the bud. I used stainless steel filled bedding compound (2-part epoxy) to fill in the chipped areas. Drill rod in the bore used to form a nice round hole again. Need to let it sit for about a week to fully harden now and just touch the counter-bores with an end mill to flatten them again.

   

   

   

   

[awemawson]

This filled me with dred imagining a patched wheel self destructing and killing you..

Then I saw the speed rating. Max rpm 150 !!!

[Highpower]

That is a good point to bring up Andrew.

I should have mentioned that this wheel is for a slow-speed wet grinder and only runs at 90 RPM. I wouldn't want to be anywhere near a wheel of this size at a high RPM. It is 10 inches (250 mm) in diameter - 2 inches (50 mm) wide and weighs 10 lbs. (0.71 stone) so I am more afraid of dropping it on my foot than anything else.

I just wanted to true up the edges of the bore so that the weight of wheel didn't cause it to settle on the drive shaft into one of the chipped spots on the edges and induce any run out / wobble problems. As I mentioned it probably wasn't necessary to do at all, but it gives me piece of mind regardless knowing the bore is as true as possible. I had to make myself new hubs for the wheels on my 6 inch Harbor Freight carbide grinder thanks to the sloppy fit of the bores and multiple voids in the cast aluminum (aluminium) factory hubs. Out of the box that grinder would vibrate itself right off the workbench if it wasn't bolted down. No bueno.

[Vinny]

I had a grinder like that (the vibration, that is). I bolted it to the bench and anytime I had to vibrate the air bubbles out of a mold I'd set the mold either next to it or on the motor and turn it on. Worked like a champ. Then I bought a real grinder!

[Highpower]

Smart! When life gives you lemons....