Thread: CBN balance

The CBN Wheels do indeed come balanced but their position on the grinder, and the actual grinder shaft may not be dead straight, which can result in side/side runout/wobble and vibration. If you are happy with the degree of wobble/vibe without these washers then you don't need to worry about the wobble washers.

Wobble washers are more about removing side wobble than balance and there is a discussion about these wobble washers here
Bench Grinder wheel balancing

After the coarse/visible wobble/vibe is minimised it becomes increasingly difficult to assess the smaller residual wobble/vibe. Even though it's a drawn out process, to make this residual wobble/vibe more detectable and correctable I use a mobile Phone "Vibration" App. By placing the phone in the exact same place on or near the grinder and measuring the vibe before and after making changes to the rotational position of the wheel washers relative to wheel, and wheel relative to grinder shaft. This is discussed in the link above

Being a cheap skate and having the necessary gear I ended up making my own .

Originally Posted by BobL

Being a cheap skate and having the necessary gear I ended up making my own .

That's not being cheap Bob.
Doing something like that yourself,
because you can,
is a great thing .

They look great, too
And thanks for your help

I've got two different CBN wheels - one his higher quality and was about $125 (marked down from $150 US) with a radius edge. I suspect it's aluminum. It is very smooth working and has worn very evenly. My grinder is baldor and seems true (I haven't checked).

The other is a $50 wheel off of ebay and I suspect that the hole is drilled mildly off center as it cuts more heavily on one side than the other (but it still works fine). I suspect that it's cast steel or something or milled mild steel as it's heavier than the first wheel despite being only 2/3rds as wide with no radius edge.

I'd wait to get any balancing gadgets until or unless you know you actually need them. I didn't really expect a $50 CBN wheel (including shipping) to be that great, and it is passable for use but in my opinion, I wouldn't buy it again. If I have to replace the first wheel, I will.

I had regular grinding wheels prior to CBN, and those needed a balancing system (I got the oneway system - it worked reasonably well). The first wheel mentioned above is better with no assistance than the traditional al-ox wheels were with the one-way system.

Originally Posted by D.W.

I've got two different CBN wheels - one his higher quality and was about $125 (marked down from $150 US) with a radius edge. I suspect it's aluminum. It is very smooth working and has worn very evenly. My grinder is baldor and seems true (I haven't checked).

The other is a $50 wheel off of ebay and I suspect that the hole is drilled mildly off center as it cuts more heavily on one side than the other (but it still works fine). I suspect that it's cast steel or something or milled mild steel as it's heavier than the first wheel despite being only 2/3rds as wide with no radius edge.

If it cuts more heavily on one side than the other the most likely cause is slight wheel wobble - putting a dial indicator on it will identify this.

Originally Posted by BobL

If it cuts more heavily on one side than the other the most likely cause is slight wheel wobble - putting a dial indicator on it will identify this.

Sorry, I should've been more clear - it's not a wobble related issue. It's a hole off center. I forgot that the cheaper wheel needed a bushing, and I would guess the bushing has a fair chance of being the problem. It still works well enough that it doesn't cause the grinder to dance or anything.

the issue isn't a left or right side cutting better, it's like 100 degrees of wheel arc gets a deeper cut than the other 260 degrees.

Originally Posted by D.W.

Sorry, I should've been more clear - it's not a wobble related issue. It's a hole off center. I forgot that the cheaper wheel needed a bushing, and I would guess the bushing has a fair chance of being the problem. It still works well enough that it doesn't cause the grinder to dance or anything.

the issue isn't a left or right side cutting better, it's like 100 degrees of wheel arc gets a deeper cut than the other 260 degrees.

Thanks - I thought you referred to the side of the piece being ground rather than the wheel itself.