Norton materials hardness scale, incl. CBN

[Steve Tiedman]

In an effort to educate myself about CBN grinding wheels, I visited the Norton Abrasives website. Unfortunately, their in-depth information is contained in a 300+ page PDF download. Anyway, an interesting table showed up on page 293, amongst the section referencing diamond and CBN products (a single category), outlining material hardness comparisons.

Gone are the days of the old saying- "Hard steel, soft wheel. Soft steel, hard wheel." Hey, remember when the Norton SG wheel was all the rage in the woodturning community, blowing the standard white aluminum oxide wheels out of the water? Time marches forward.

If you'd like to know more, this link should take you to the catalog download. Nearby it includes information about truing and dressing a new diamond or CBN wheel for initial use. I don't know that it applies to hand held bench grinder use, but it is information for the purpose of learning. (Warning- big download for cell phones.)
https://www.nortonabrasives.com/sga...tonindustrial-7362-lr-bookmarked.pdf#page=295

Steve.

 

[robo hippy]

The first CBN and diamond grinding wheel were before they figured out the electroplating process to bond it to steel hubs. My first set were 1 inch wide, and had 3/16 inch of material bonded to an aluminum hub. I think Woodcraft had a diamond wheel like this, once upon a time. They did work fine, but they did need to go back to the maker for cleaning and resurfacing. I had called Norton looking for some thing better than standard wheels and was asking about diamond. They told me that CBN would be better, and there was actually some one here in Eugene that could make them for me. I think it was 2 or so years later when the D Way wheels came out. It might have been the Optigrind wheels that were first on the market for turners, but can't remember.... The place in town did give me some broken chunks of their very hard aluminum oxide grinding wheels to clean off my wheels. It was far harder than what we used to use for our sharpening wheels.

robo hippy

 

[Bill Blasic]

The first I saw and bought I believe were the Optigrind that a man and his daughter from Austria were selling at the AAW Symposium. Expensive but they still look brand new today.

 

[Steve Tiedman]

I guess I'm going to hijack my own thread, but other than the obvious weight difference (and price), are there any quality or performance issues between steel and aluminum wheels for CBN? I understand the electroplated abrasive method is preferred to bonded.

Steve.

 

[robo hippy]

I am fairly sure that Cindy Drozda sells the Optigrind wheels now. She was friends with the owner, who has passed away. First name was Dietmer. Met him at the San Jose Symposium. I did pick up one of his wheels there. I think it might have been his last one he had with him.

As far as which is better, Steel, aluminum, or plastic hubs, I don't know if there is any real difference. There were concerns about the bonding to the aluminum, and I heard of one case where some of the plating came off, but only one, and if it was a regular thing, it would have been all over the forums. I don't know if there is any quality difference between the CBN used on the wheels, though they both claim to have the best stuff out there. If I had to pick which one 'looks' the best, I would probably say the Cuttermaster from up in Canada. Theirs were originally designed for the CNC machine bit sharpening. His variable speed grinder will handle diamond because of the variable speed, which will go far slower than our slow speed grinders.

robo hippy

 

[Steve Tiedman]

Thank you, robo.

Steve.