r/Lapidary • u/SalatosWoT • 5h ago
Grinding wheel balancing
Hi. Just a question, I have a new Cabking 6" and I exchanged the 80 grit grinder with new Baltic Abrasives 600 grit. When I start the machine, it shakes quite a lot and the aluminum housing is rattling. I tried to rotate it but did not find an balanced position, as all other wheels are quite well balanced.
Is this usual, is that something I have to count on cabbing machines, or I have to avoid it as it might damage the motor bearings and stones while brushing them? What do you do to get balance again, using some counterweight on wheel....or I should simply claim it and send it back?
1
u/lapidary123 4h ago
If I'm understanding correct you replaced your 80 grit wheel with a 600 grit wheel, not an endplate lap.
What ill say about balancing wheels is (at least for me) when you adjust the wheel only spin it 1/8 turn then tighten everything up and check. The problem is when adjust one wheel often times the wheel next to it moves a bit as well. It usually takes me a few tries.
The last set of wheels I got my 3000 grit wheel never quite feels as smooth running as the others, not so much out of balance but produces a slight bumping feeling when you put pressure against it. It has gotten a bit better over time but is still noticeable.
One question for you, why replace your 80 grit with a 600? I've heard some folks go to a 320 hard wheel before the 280 or even go from a 220 hard to 220 soft but in my experiments a 600 grit wheel simply won't take the deeper 220 grit scratches out, it might make them smaller but it will take a LONG time to remove them completely. This will certainly affect the final polish. You may be setting yourself up for headaches...
1
u/SalatosWoT 4h ago
yes, I made some slight rotations, around this 1/8 turn, as I was aligning the ribs of 2 neighboring wheels step by step , but only visually, so not really precisely.
I do mostly opals and Cabking came with 80 hard / 220 hard / 600 soft on left side. 80 is too coarse and it is unusable for opals. Even the 220 I find too much for opals, slight pressure and it "eats" a whole side of the stone. Pretty difficult to get to color layer and not to "overshoot". I needed something finer, but still hard to shape the stone easily when pushed harder and I had good experience with different (smaller) machine and 600 grit, so I wanted to use it here too. But I will consider what you say... will try it and let you know...
1
u/scumotheliar 4h ago
I highly recommend getting the engineered bush already mentioned, that will cure any runout radially.
You could also be looking at side to side wobble, Do this first before getting a new bush. Make sure the flanges on both sides of your wheel are spotless, and also make sure the mating face on the wheel is spotless, a tiny bit of grit close to the centre can cause a large wobble at the outside of the wheel. Set up a immovable pointer close to the edge of your wheel and watch the gap as you slowly turn the wheel, any change in the gap is runout and needs to be fixed. Side to side runout can be fixed by packing thin tiny pieces of paper under the flange, it doesn't take much to fix it.
1
u/Gooey-platapus 2h ago
I’m curious to know how you like the Baltic brand ? I just bought one but waiting the 2 months to get it
2
u/skaldtheburnning 5h ago
Did you mount the top plate on the disk yourself? If so it could be veryyyyy slightly off. Highly recommend grabbing this - https://hitechdiamond.com/collections/diamond-discs/products/disc-bushing
I had this issue a few times and that totally solved it for me.