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:rolleyes:.

[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
312701312702


newer set-up
312703312704312705

[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

[Mike Holbrook]

I have the newer Delta grinder. My D-Way wheel seems to take up a little more arbor length than my WoodTurner's Wonders wheel, with the double washer wobble adjuster. Not sure if Ken made a change to his wheels or Dave just uses thicker washers. I know that when I bought my wheel from Ken he was making some changes to his wheel designs and he was aware of the issue of shorter arbors on newer machines. The bolts on both wheels have threads that the arbor has not engaged, just one or two more on the D-Way. Then it could be that my Delta arbor is different lengths on either side of the wheel. I made a post about buying another grinder. One of the reasons being the short arbor length. On my machine I have not found a way to get the arbor out past the outside edge of either wheel nut. I talked to Dave about the nut not being threaded entirely onto the arbor. He seemed to think I had plenty of engaged thread, still makes me a little nervous. Is there any way to be sure if any issues with CBN wheels are the result of the wheels or the grinders, short of buying a Baldor Low Speed hand tuned grinder from Tools for Working Wood?

[Mike Holbrook]

I just did a little research on the Tools For Working Wood "Gramercy Custom Tuned Baldor Bench Grinders" page. A major part of their tuning package is regrinding all four flanges on both sides. Everyone seems to acknowledge the issue of the washers or flanges used to hold the wheels in position not necessarily being precisely made. I understand from the vendors I have talked to that companies making wheels and grinders outsource their washers/flanges. The Gramercy offering attempts to remedy this issue. Although the cost of hand grinding 8 surfaces may be high, I think it sheds light on a major issue. Any ideas where we might find big hand ground flanges made to exacting tolerances like the ones Gramercy tunes?

[Reed Gray]

I have heard of one or two cases where the wheels were not true. Given the numbers that have been made and sold, this is not unexpected. I did find with my wheels on my Baldor, that if I used the cheap big box store washers to space it away from the inside of the wheel guard, I would get some wobble in the wheels till they got up to speed, then the face ran true. Not sure about the sides as I never use that feature. I have one of the old blue no name grinders that Woodcraft used to sell. It is slow to come up to speed, and has more of a wobble in it. It still runs pretty true, but not as smooth as the Baldor. They are D Way wheels. I haven't tried the wheels from Ken Rizza. I have too many sets of wheels as is.

robo hippy

[Mike Holbrook]

Has anyone tried the "Razor Sharp Edgemaking" wheels that Woodcraft seems to be so sold on? It says they are laminated paper, one for rough work and one for buffing. They say they run much cooler. They offer a kit with a grinding wheel, a buffing wheel, silicon carbide, grease, and jewelers rouge for $56.99.

[Bruce Whitaker]

Does anyone use their CBN wheels to sharpen drill bits on a regular basis? Has anyone had problems with the wheels loading up from this?

Bruce

[Reed Gray]

I have sharpened just about every thing on my CBN wheels. I just got done touching up some drill rod that is not hardened yet. No loading. Same with bench chisels and drill bits. Cold rolled steel will clog it up, same with aluminum, brass, copper, and some stainless steels.

robo hippy

[Eric Gourieux]

I emailed Dave at D-Way, and he said that he has never heard of anybody "wearing out" a CBN wheel. He said that he still uses the same wheels that he started with 7 years ago. So, as many of you suggested, I have probably loaded mine up with cold rolled steel while fabricating some of my hollowing tools. I used my old grinder and wheels for most of it but probably used my CBN for some fine tuning. Dave suggested reversing the wheel and grinding a large scraper to try unloading. Tomorrow, I'm going to try power washing my wheel to see if that does any good. So far, it still seems quite smooth.

Dave also mentioned that he uses his 80 grit wheel for his bowl gouges. I'm going to start doing that, too. I'll use my 180 grit for 1/4" gouges and hollowing tips.

Regarding the suggestion that I may be able to resurface the wheel. Dave said that the CBN material is simply too hard to remove for resurfacing to be feasible.

[Mikey Green]

I can't attest to how well they work, but Packard Woodworks advertises CBN cleaning sticks, which will apparently help with restoring (to some degree?) your CBN wheel.

[Reed Gray]

When researching my article that I wrote on CBN wheels, I talked to Brad Packard about the cleaning stick. They are intended for the matrix type CBN wheels, not the electroplated CBN wheels. Article is up on my web site, www.robohippy.net I can't remember if I wrote about that cleaning stick or not. Similar to the very hard aluminum oxide wheel that I used on my first wheels before the plated wheels were available to us.

robo hippy

[Russell Neyman]

I wonder if that carburetor cleaner spray would work?

[Reed Gray]

Dave Schweitzer said he has used oven cleaner. The problem with a loaded wheel is the softer steels are kind of bound to the wheel, and a solvent generally does not remove them. That type of loading can not be dissolved. Ken Rizza did comment that he has used kerosene. I can see that it might lubricate the wheel, and maybe get under the loaded metal and help loosen it up so when you take a scraper to it, it may come off easier. Never tried it though. Cindy Drozda had a clip up on You Tube where she was using a paint brush with oil on it to keep the old Woodriver (Woodcraft brand) diamond matrix wheel clean. I don't know if a hard Aluminum oxide might clean off the bound metal on the CBN wheels without removing some of the CBN.

Well, I had to try the AlO out... It did clean off the sludge from wet wood on my wheels, and didn't effect the cutting action at all that I could tell. Just went back to the shop and loaded a bit of cold rolled steel on my 180 grit wheel. Not a heavy loading, but you could hear it 'ticking' and when I turned the grinder off, I could see minimal build up as shiny spots on the wheel. If you have ground soft steel on the wheels, you will recognize the sound. I applied the hard AlO to the wheel, then took a scraper to it, and it seemed to be clean. So, maybe that will clean up the wheel, though I would not suggest it as something you want to do on a regular basis. Probably any old grinding wheel could work, especially one that you aren't going to use any more, or one of the clean up sticks from Packard. This was just a one time test, so 'individual results may vary'. Since the wheel no longer cuts, you don't have anything to loose I guess.

robo hippy