Question on CBN wheels...

[Matt Owen]

I've read so many glowing reviews of the CBN wheels by DWay Tools that it has really piqued my interest. I'm currently using an AO wheel, 150 grit, and I get a pretty good edge off of the grinder. My tools don't bounce on the wheel while grinding, and I feel that overall it's doing a pretty good job.

With that said, what would I gain if I invested in one of the CBN wheels? I've read that the wheel is extremely smooth and that it gives a nice edge, but is the edge that much better than an AO wheel will give? Does the edge last longer? What qualities make it worth the extra expense? I understand that I won't have a wheel that is constantly getting smaller, and I won't have to true the wheel or have the grinding dust, but none of that really makes a big difference to me as it hasn't been a problem for me in my 7+ years of turning.

I don't know anyone with a CBN wheel to try, so I'm hopeful someone can set me straight on all of this. Thanks for your help.

Matt

[Josh Bowman]

Matt, they cut clean, some of that is due to the absence of bounce. My drive toward mine was the balance issues. If you have no wobble or bounce in you wheels, then save the $200 bucks and use that money for some other toy..... uh, tool.

[Jon Prouty]

I was tired of fighting my AO wheels for balance and true... I was not going to throw more money at getting them better so I bit the bullet and bought a CBN wheel. Very happy I did. One thing that doesn't get discussed as much is the ability to remove the shroud as there is no danger of the wheel coming apart. I like this as the visibility is much improved and allows more freedom without hitting the guard. Not having that dust is huge! It is a joy to use and one of my favorite toys.... errrrr tools.

The edge doesn't last longer, it isn't a perfectly honed edge, it isn't like off a Tormek - to me it is an edge like off a good AO wheel that is perfectly balanced and true and clean. I don't have to think about the stupid wheel being the problem anymore - I have enough other problems to deal with as it is.

Hope this helps - I think Dave would sell a lot more of these wheels if he had a loner one that he let people try out as long as they paid the shipping both ways. Then if they decide to buy one, Dave absorbs shipping on a new wheel. Dave, you can use this business model for only the price of a new gouge or some other tool

Later,
Jon

[Bob Bergstrom]

Along with the many things you have read the one biggest difference is in my scrapers. I use a scraper in the bottom of a bowl and sometimes rolled over for shear cutting. I am now able to take the lightest of light shavings off the ridges and interior of the bowl. Whispers of shavings. As far as cutting longer that is relative. It may be sharper than a 150, but my tolerance for dull edges has become more senitve. It is hard to tolerate much of a drop in the cutting ability of the tool. I use mostly powder metal tools and sharping is quick, efficient and consistent.

[Jeff Nicol]

I was able to find one cheap that had been resurfaced on the bay, it is a 5" but works for what I wanted it for. The biggest plus for the CBN wheels is now that a lot of the new super tools (hard powdered metal) and the use of carbide a lot these days, and the CBN wheels sharpen these materials much better, or in the case of carbide is the only thing besides diamond or some of the green silicone carbide wheels. The CBN wheels are great for fast material removal when shaping tools or fixing one that was damaged in some way.

As most of us who turn are toolaholics, another tool or sharpening thing is just a ++!

Jeff

[Mark Levitski]

I have white AO wheels and my biggest irritation is that they all too quickly load up with metal and need to be dressed all the time. I've been lucky not to have any wobbles or vibration issues. The less expensive WC slow speed grinder that I bought about 5 years ago has done just great. And except for that loading up so have the wheels. Sounds like I might be in heaven with a CBN though!

[Bob Bergstrom]

I was able to find one cheap that had been resurfaced on the bay, it is a 5" but works for what I wanted it for. The biggest plus for the CBN wheels is now that a lot of the new super tools (hard powdered metal) and the use of carbide a lot these days, and the CBN wheels sharpen these materials much better, or in the case of carbide is the only thing besides diamond or some of the green silicone carbide wheels. The CBN wheels are great for fast material removal when shaping tools or fixing one that was damaged in some way.

As most of us who turn are toolaholics, another tool or sharpening thing is just a ++!

Jeff

Don't know if grinding carbide is a good idea on cbn wheels.
Here is a quote from their web site. " You should only grind high speed steel on a cbn wheel. Do not use it for mild steel or carbide".



http://www.d-waytools.com/images/CBN%20INSTRUCTION%20SHEET.jpg

[Prashun Patel]

The biggest benefit is convenience. If truing and balancing is not an issue for you, I dont think its worth the investment. I will submit though that I thought my a o wheels were fairly well balanced until I got a Cbn. Then I found out what true was. That improved my cutting edges. If you are sure yr wheel is as true as a Cbn then I dont think you will notice improvement in cutting edge.

[Clint Baxter]

One other advantage to the CBN wheels from Dave is the width. You're getting a 1-1/2" wide wheel where the 8" AO wheel is only 1" wide.

Clint

[Ralph Lindberg]

Let me tell a couple stories (Dave is a local and in the club)

Last month the DW and I were taking a two day class from Eli Avisera. At the start of the day Eli was talking about sharping tools and said "Dave has changed the way tools will be sharpened, forever"

At one point she walked over to the grinding station, which had two D-Way CBN wheels, when she finished she walked over to me and told me "as soon as we can afford them, we are going to get them"

The day after the class was the Olympia Turning club one-day Symposium. This year the prime demonstrator was David Ellsworth. The wheels on the grinding station where also D-Way. David stated that they gave the best finish off the wheel of any system he had seen and that he had converted his own grinder.

On the flip-side, Mike Mahoney was through last year, he stated he didn't like the smooth edge the CBN wheels gave the tool, he preferred the more serrated edge the AO wheels give.

Personally, I believe that the better the quality of the edge, the better the quality of the cut and, hopefully the finer sand-paper grit you can start sanding with.

Lastly, the DW is getting a CBN wheel for our anniversary (the up-side of being married to another turner)... She is also getting a piece of jewelry as I may be crazy, but I am not stupid

[Reed Gray]

I don't feel that they give a superior edge, although, I do prefer the burr on my scrapers to what I could get with a Aluminum oxide wheel. You can get similar edges on your other tools with Al O wheels or any other matrix type wheel. If you have a wheel on your grinder now, use it up and get a CBN wheel when you need to replace it. You could just bite the bullet and do it now because they will become the standard for the woodturning industry/hobby. They will outlast by far, any comparable $ amount you will spend on any other wheels out there, as in you will wear out several of the Al O wheels before you come close to wearing out the CBN wheel. You never have to clean it. It will never change shape. It comes spin balanced. You can not crack or chip it. If you over tighten the nut, you can not crack the steel hub. There is no dust from cleaning the wheel. There are steel filings that will land on your bench, so a plastic baggie with some magnets in it will get most of that. If you lay a tool down by the grinder, after sharpening, and then pick it up, it will have a metal dust beard. A tap on some metal will demagnetize it, or you can get a demagnetizer at the big box stores. I had some matrix type CBN wheels maybe 6 or so years ago before the electroplated ones came out. One of them still has about half the matrix left on it, and I was turning 700 or so bowls a year. I now have Dave's wheels, and love the extra width. Once you get them, it is like variable speed on your lathe, you never want to go back.

robo hippy

[Greg Bender]

I also had a myriad of CBN questions that have been addressed here. Now I have one more, I guess most owners have one cbn wheel,which grit is the best choice for a first purchase? I've seen 80 and 180 ,are there any other grits available?
Greg

[Dave Mueller]

I just got one from Dave at D-Way and am really pleased with it. If you buy one, get the correct bushing for your grinder. It does not appear that there is any runout between the bushing and the grinding wheel so their relative orientation doesn't matter. However, when you mount the wheel, there will probably be a big difference in the runout between the bushing and the shaft of your grinder. At the initial orientation, I got about 0.022" side to side and 0.018" radially. I put a mark on the end of the shaft and on the bushing and then rotated the bushing about 15 degrees and measured again. Keep doing this until you find the minimum runout. Mine had a "sweetspot" of about 10 degrees arc where the runout was approximately 0.002". At this point, it ran true without any vibration. This adjustment is critical because you cannot true the wheel to balance it. I got the 180 grit, which is plenty aggressive enough. I think the 80 grit would be too rough. At AAW, I talked to Dave from D-Way and he said he has been using the the wheel he had at the show for about two years and it still worked.
Dave

[Reed Gray]

If I was to get only one, I would get the 180, but I do have both. The wheels are fairly coarse when new, and do break in a bit, but the 180 really removes steel fast. Only a light touch is needed.

I do get a minimal amount of sideways run out on my wheels, and I have a Baldor grinder. The problem seems to be more that the bushings/flanges/washers that come standard on the Baldor grinder are about 3 3/8 inch wide, are made for solid faced wheels, and don't seat as well against the smaller 1 1/2 inch hubs on any of the other CBN wheels out there. The run out is almost totally absent when the wheels are up to speed. I don't have machine shop tools so can't give .00whatever measures, but if I lay a gouge on top of the wheel as it spins, like you do on a bowl blank to see if there are any flat spots, it stays on. Thus far, all are 80 and 180 grit.

robo hippy

[Matt Owen]

Thanks to all for the information and advice. I think I'll stick with the AO wheel until it wears down enough to no be usable, and then take another look at the CBN wheels. Thanks again!