CBN B-gone

[Eric Gourieux]

I've been using my 6" CBN wheels for a few years now, and my 180 grit doesn't grind very well anymore. I sharpen my Thompson 1/4" and Thompson/D-way 3/8" bowl gouges with the 180 grit wheel and my Thompson/D-Way 5/8" gouges with my 80 grit CBN wheel. The 80 grit is as good as new and is used less often.

Has anybody else worn out their CBN? I assume mine is worn out, since I use it more often - and it's 6", which, I assume, would wear faster than 8".

I'm seriously considering the radius CBN from Woodturningwonders as a replacement. I don't see the 6" radius wheel on D-Way's site. Has anybody used both and can compare the two? I have seen some comments about the bushings from D-Way being more balanced that the wheels from Woodturningwonders, which don't need the bushing for my 1/2" arbor.

[Reed Gray]

Well, I have had my D Way 8 inch wheels for several years now, and they do cut a lot slower than they did when they were brand new. The edge is much more polished, but the metal still comes off pretty fast. I have a set of radius wheels, and don't use them. I just can't see them for any thing other than hollowing points. I tried doing the sides of my swept back scrapers on the radius edge, and got a washboard edge rather than straight. You can clean your CBN wheels up a bit using Ajax or Comet abrasive cleaners and a plastic bristle brush. Mine are pretty black from the sludge from the wet wood I turn. I have cleaned them up a few times before, but haven't bothered in a year or two. They still cut just about as fast as standard wheels. If yours have loaded up because of sharpening non hardened steel on them, you will see, feel and hear some run out when sharpening. Spend some time with a scraper will clean most of it off fairly quickly.

robo hippy

robo hippy

[Bob Bergstrom]

Remount your old oxide wheels and your cbn's will feel a lot better as memories of the oxide wheels come back.

[Russell Neyman]

I've heard you can clog them up grinding low grade steel.

[Thom Sturgill]

I have both a D-Way 180 grit wheel (flat) and a WoodturningWonders radiused wheel with the side plating at 350 grit. Dave's adapter and wheel were rock steady. The shaft needed a little sanding to get a fit. The other wheel was drilled for the 'right' diameter but displayed a bit of wobble as they were an easy fit. I bought his sperical washers and they helped after playing with the placement. I still find the side grind 'iffy' but usable as there is a very slight bit of wobble tough the face and radius are stable.

The pair of wheels is right at the capability of the Delta grinder and I have to occasionally spin the wheels by hand to start them.

[David Delo]

I have both a D-Way 180 grit wheel (flat) and a WoodturningWonders radiused wheel with the side plating at 350 grit. Dave's adapter and wheel were rock steady. The shaft needed a little sanding to get a fit. The other wheel was drilled for the 'right' diameter but displayed a bit of wobble as they were an easy fit. I bought his sperical washers and they helped after playing with the placement. I still find the side grind 'iffy' but usable as there is a very slight bit of wobble tough the face and radius are stable.

The pair of wheels is right at the capability of the Delta grinder and I have to occasionally spin the wheels by hand to start them.

Thom,

Did you have any problems with your shaft length on your Delta grinder using Ken's wheel? My old Delta grinder burned up awhile back and I had his alignment washers in place and they seemed to work very well with any wobble. As you can see by the first 2 pics, plenty of shaft length but when I bought the new Delta grinder, the shaft length was shorter and couldn't use the alignment washers (not enough length). Just using a flat machine washer under the nut currently and it works okay but there is just a hint of wobble.......but doesn't seem to effect the radius on the wheel for sharpening scraper, I get a nice even burr on the tool. Satisfied with the wheel but a little disappointed with Delta (imagine that) changing shaft lengths.


old set-up
CBN 3.jpgCBN 2.jpg


newer set-up
www 1.jpgwww 2.jpgwww 3.jpg

[Reed Gray]

Russell, You can load up the wheels a bit with non hardened metals. You can see and feel the load up. By sharpening a scraper on it, you can clean most of it up. It takes several sharpenings if you get much on it. Bench chisels are fine, lawn mower blades, old carbon steel tools, brass, aluminum, and bronze are not okay. Better to use standard wheels on them. I have a long article up on my web site (robohippy.net)

robo hippy

[Eric Gourieux]

David,

Dave talks about the shorter shafts on his site (D-Way). He specifically mentions the shorter shafts on the newer Woodcraft grinders, but it may apply to you, as well.

[Thom Sturgill]

Thom,

Did you have any problems with your shaft length on your Delta grinder using Ken's wheel?

No, my grinder is several years old, so looks like your 'older' setup.

[Russell Neyman]

Reed, did you ever do that experiment with upside (reverse) scraper grinding Ralph Lindberg suggested?

[Dale Bonertz]

Eric
I know someone who wore his cbn out in about a year. He makes tools so he used it extensively. He decided for the money he would just go through the other type of wheels. They also cut faster for him when shaping (the other wheels). I won't part with mine (cbn) but I don't use them the way he does.

[Reed Gray]

Russell, I did experiment with the upside down burr, which Jimmy Clewes uses, but don't remember Ralph suggesting, though he probably did. If I take my platform, slide the last hole out to the frame and slip the pin through, when upside down, it is about an 80 degree angle. It does provide a nice sharp burr. I don't think it is any sharper than the right side up burr, and for sure, it didn't seem to last as long as the right side up burr for heavy roughing. On shear scrapes, there may be a tiny bit of sharpness difference. I had asked Jimmy, after finding out that he was getting a CBN wheel to experiment with it, but he forgot. My theory is that when it is right side up, the CBN wheel kind of burnishes a burr on the top, similar to using a hone on the face of the scraper. Jimmy thinks that by dragging the burr off the bottom side you get a sharper burr. Don't really know.

Dale, Dave Schweitzer has a 40 grit 10 inch CBN wheel on a high speed Jet grinder that he uses for his shaping. I don't know how long he has been using it though. If all you did was make and shape tools, and used your CBN wheels for that, then maybe you could wear one out. I am still trying, though I don't turn as much as I used to. Too busy inventing.....

robo hippy

[Dale Bonertz]

Reed,

Just to be clear it wasn't me who was making the tools. I only make tools for myself and that isn't enough to ruin much of anything, maybe pride

I think the person in question was using either a 180 or 80 grit which may play into why it wore so quickly for him. He also makes tools commercially, think production like Dave. I don't know for sure but he may have used it on crappy steel.

Anyway like I said I am not giving up the ones I have. I still don't think the cbn hold an edge as long as my old 60 grit norton wheel did, for my roughing out bowls. The 80 grit cbn wheel seems to help some with the edge holding but still not as long as the old 60 grit. Not having to breath that silica dust makes it worth it to me to sharpen a bit more often.

[Wes Ramsey]

I haven't delved into the CBN world yet, but I would contact the manufacturer before you toss the wheel. I've read that some will restore the wheel for a much smaller fee than buying a new one.

[Reed Gray]

Dale, some time I need to try a 60 grit wheel. I don't think I have ever had one. Since I do all of my roughing with scrapers, I probably don't have the feel for gouges that you do. I always sharpen for a finish cut though. I can't remember when I have roughed with a gouge till it was dull enough to need sharpening.

robo hippy