auto-balancing bench grinder arbors

[Gramps43]

Matt, I think you need some heavy oil that lets the balls move but holds them in place when they have reached the balance point. That of course would require seals to keep the oil in there while everything is spinning willy-nilly.

[mattthemuppet]

could be, although centripetal force (or lack of it) keeps them in place as far as I can tell once the grinder is up to speed. They only roll around on start up and just before the grinder finishes slowing down to a stop. I tried grease and it didn't let them move at all. I don't think oil would hurt but I don't think it's necessary either, plus the downsides of sealing it in as you said.

I'm getting some 3/16 balls tomorrow, just can't stop needing to itch that scratch and see if I can fully balance the wire wheel.

[C-Bag]

You go Matt. I KNOW the itch, when you are so close but not there. Some folks are with ok with 75% I'm too OCD to let it go. All of this is kinda counterintuitive for me.

It might be one of those things where less/larger bearings would work. Dunno. I'm somewhat skeptical of any kind of oil in there too.
Glad you've decided to work all the way through.

[Bloy]

Thanks for the article.

[mattthemuppet]

you're welcome!

quick update. Finally got some time to recut the groove for 3/16 balls and I made it wide enough that the balls could stack in one spot (in a zig zag pattern). Filled the groove a 1/3 full, spun it up without and then with the wire wheel. Still some vibration and no detectable difference from the 5/32 balls, but a noticeable difference from no balls. That'll have to do, works well and what vibration there is doesn't affect the finish I get from the grinding wheel.

My guess is that it's just a crappy wire wheel - got it from Lowes and the hub is visibly out of round with respect to the center hole. I'll keep my ears and eyes open for a better one at some point.

[C-Bag]

you're welcome!

quick update. Finally got some time to recut the groove for 3/16 balls and I made it wide enough that the balls could stack in one spot (in a zig zag pattern). Filled the groove a 1/3 full, spun it up without and then with the wire wheel. Still some vibration and no detectable difference from the 5/32 balls, but a noticeable difference from no balls. That'll have to do, works well and what vibration there is doesn't affect the finish I get from the grinding wheel.

My guess is that it's just a crappy wire wheel - got it from Lowes and the hub is visibly out of round with respect to the center hole. I'll keep my ears and eyes open for a better one at some point.

Matthemuppet, have you seen the Oneway Wheel balancer? I ended up going that route because I had spent hours already on this silly 8" grinder of mine and it was still scaring me to death. I think it's probably and easy thing to copy and make yourself especially the balancer jig. My fine grit wheel was a real challenge and it's got it running smooth, something I never thought I'd accomplish. This is not an auto balancer, but it sure works good. I did a little write up in the tools and tricks section of HMT.

[mattthemuppet]

thanks for the reminder c-bag, I looked up your post and enjoyed the read. Much appreciated. It would be an interesting option for sure and one I'll keep in mind for the future. Right now though I'm itching to get on with other projects I need to finish up a bearing remover and some spacers for my bike bottom bracket bearings.

[C-Bag]

Yup, know the feeling, that's why I opted for the Oneway. Just didn't have time and had to get 'er done.

Good luckmwithmthe nearing remover and bottom bracket spacer.

[mattthemuppet]

thanks, nearly finished it, just have to part off the bearing pusher. Also made a couple of spacers by trepanning into the face of the slug at the desired ID, turning down the OD and then parting off. After that all I had to do was turn the nub down to the ID of the bearing. I was rather pleased with myself about that

[suther51]

I do not have any personal experience with this but have heard of using lead shot in car tires as an auto balance. In this case I would wonder if they would hold up, nothing like filling the air with lead dust. Just a comment. Good idea though, I have an old arbor shaft I'm looking to get hooked up when time allows.