Partial success super tuning grinder

[tvrgeek]

Like a lot of folks here, I have the Rikon grinder with a Wolverine setup.
As expected, a lot of vibration. Trued the wheels, but that was about all. Eventually I got smart and put on a CBN wheel from Woodcutters. Really nice. I did a relatively finer grit for light touchups. HUGE improvement in vibration. But not perfect. So research time.

Like all ot the internet, a lot of sketchy stuff out there. One Way does make counter-weight washers which I bet work well, but I decided f I could just beat it to death with creativity. Besides, their kit required 1 inch openings and my wheels are al l5/8 or 1/2. Good wheels being expensive enough already.

OK, best static balance I know of is the parallel knife/axle setup. Looking around, BINGO, the rails on my Jointmaster. Raised and shimmed it for level. First I trued the wheels on the grinder. A 1/2 inch bolt and a grinder wheel bushing and I was in business. Yup. Close enough. Sure, a precision drill rod would be better, but rotating the bolt in the wheel did not change any of the results. I then used a diamond bit to hollow out a little of the disk on the heavy side. It works! I was able to get three wheels static balanced. Seems the density of the wheels varies. I did of course stand to the side when spinning it up the first time.

Results. Well, only a little better. Worth a couple hours if for just the education. I think to get a really smooth machine, I should just buy their 60 grit BCN wheel. I only use this grinder for hard steel. I use my old 5 incher for soft junk. It may be smart to get another set of the OneWay adjustable washers for the ceramic wheel as there is a couple mm of wobble. The vibration could still be from that. I have not tried adding paper shims to see if I can reduce it that way. Maybe after chores.

In hind sight, I could have ground closer to the edge of the wheels as I would never use more than an inch of them.

 

[Warren]

When I bought my CBN wheels from woodturnerswonders.com, they included (as a promotion) 2 sets of precision ground washers. They are only a few $ and the wheels run smoothly with no vibration.

 

[tvrgeek]

I said Woodcutters. My mistake. That is where I got my cutter heads. My CBN came from woodturners. Both good folks!

I was looking at all my washers. They all look the same, stamped steel, but a careful look showed some of them were ground flatter before plating. I suspect the set that came on the Rikon. The ones of my old 6 inch back-of-the-truck-before-Horrible-Freight, were not. Gad, that was a long time ago. Anyone remember those traveling cheap tool trucks? Anyway, I need to investigate why the wobble on the stone wheels. Is the center hole too large? Off kilter? I am not sure the washers are pushing it askew. If so, I would think there would be a lot of machined aftermarket washers.

 

[bowman]

The center holes in the stone wheels are not exactly prescion holes, expect wobble. That's why you have the dressing tool.

 

[tvrgeek]

The center holes in the stone wheels are not exactly prescion holes, expect wobble. That's why you have the dressing tool.

That explains some of it. Sure, easy to dress it round, but not side to side. There is not enough flange on the motor side to holed them square, so I guess it means shims.
Smart would just wait for a sale and grab a Woodturners 60 or 80 grit wheel.

 

[Mark Johnson]

When I bought my CBN wheels from woodturnerswonders.com, they included (as a promotion) 2 sets of precision ground washers. They are only a few $ and the wheels run smoothly with no vibration.

This is also my experience. no vibration when using the washers.

 

[tvrgeek]

The CBN wheels are also far better balanced, round and drilled better. All around good.
I am going to try paper shims for the wobble on the stone wheel as soon as coffee is ready.

 

[tvrgeek]

Second time around with more confidence. Fine tuned the static balance and used a couple layers of blue tape to cut the wobble in about half. Now very smooth. You can set a washer on top of the motor and it won't fall off.
I wonder if one cast the center hole with JB Weld and drilled on the drill press if a more accurate center hole would be a real fix and let you swap wheels without adjusting them. I did use up two little cheap diamond burrs getting the balance. It took a lot more material out than I expected. I wonder if balance differs between brands. My wheels are the no-name white ones that came on the Rikon. I have a 6 inch Norton wheel and it was very close to balanced.