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George Conklin
03-25-2014, 1:56 PM
Sorry if this has been covered before, but this will be another opportunity to practice your typing skills:D
I understand the benefits of the CBN wheels such as the wheel doesn't get smaller balance is better and your tool doesn't heat up, but I'm curious about the edge that this wheel produces. Is it better than a standard type grinding wheel?

Larry Matchett
03-25-2014, 2:02 PM
You get a much better edge especially on harder steels like the powdered steel in Thompson Tools.

Roger Chandler
03-25-2014, 2:21 PM
Believe what Larry just said! ;) Superior edge is what I call it!

John Keeton
03-25-2014, 2:48 PM
Just read this recent thread (http://www.sawmillcreek.org/showthread.php?215703-Sharpening-System-Overhaul).

Thom Sturgill
03-25-2014, 2:55 PM
Cindy Drozda had a blog article (http://cindydrozda.blogspot.com/) about CBN and high vanadium content. Basically, the vanadium carbides can not be cut by AI wheels, rather the carbides (microscopic) are simply knocked out of the steel so rougher edge (on microscopic scale) and not as long lasting since the vanadium provides wear resistance. CBN is designed to cut the carbide, thus sharper edge and better wear resistance. All of the HSS we use today has some vanadium (M2 - 2%, M4 = 4%, V10=10%) and to get proper mixing is powdered metal according to Doug Thompson. Otherwise you would get detectable lumps of vanadium in the steel.

BTW, Cindy converted to buying Doug's steel and grinding it to make the tools she sells. She also now sells a CBN wheel.

Ralph Lindberg
03-25-2014, 3:40 PM
As noted, the CBN produces a cleaner cutting edge then a friable wheel

That being said, not everyone prefers a clean edge. Mike Mahoney for one prefers the serrated edge of an friable wheel.

Me, I like the cleaner edge

Scott Hackler
03-25-2014, 3:47 PM
As a person that is obsessed with a razor sharp edge on my tools, I have honed micro bevels on my tools for years. Straight off the AO wheel that comes with the Woodcraft grinder. I just didn't like the edge off the AO wheel. Now that I have Dave's CBN wheel, I do not hone immediately off the wheel, but because I am lazy and impatient... I do still hone the edge 3-4 times before I go back to the grinder. I can hone a sharp edge in less than 10 seconds and it takes me a minute or two to do the grinder thing.

I really like my CBN wheel and recommend it for anyone wanting a very clean and sharp edge, with NO burning of the steel and no stinking dust from the dressing of the wheel.

Reed Gray
03-25-2014, 7:35 PM
I found it interesting that in the recent Doug Thompson sharpening video, he does all of his sharpening with more standard wheels, and very coarse. I had CBN wheels before Doug was making his tools, so I don't really have any experience with the harder metals on aluminum oxide or the newer ceramic wheels. The old CBN wheels I have look like the Diamond one from Woodcraft (3/16 thick matrix of abrasive and a binding agent on an aluminum hub), and they left a highly polished bevel, even the 80 grit. The electroplated wheels like D Way also leave a nice polish as well. Some day, I may have to experiment.

Scott, with platform sharpening, it takes about the same amount of time it does to hone. Yes, it really is that fast and that easy. Learning, quoting Yogi Berra is "90% mental, and 10% in your head".

robo hippy

Tom M King
03-25-2014, 8:18 PM
Yes. not to mention faster. many times faster. I forgot to say Smooth, so I added the picture below. I sat the machine screw on the head first, but that was too easy so I turned it over onto the other end. Then when that wouldn't budge, I grabbed the closest thing at hand, and it was the old forged nail. When that wouldn't move I found the coin in my pocket. I had bought a Dewalt grinder, but it didn't do the wheel justice so I sent it back and ordered the Metabo.

Scott Hackler
03-25-2014, 8:55 PM
....
Scott, with platform sharpening, it takes about the same amount of time it does to hone. Yes, it really is that fast and that easy. Learning, quoting Yogi Berra is "90% mental, and 10% in your head".

robo hippy

You mean a platform like the RoboRest vs the Vari-Grind jig? :) (been meaning to order one of either your rest or Stuarts, just haven't taken the time to do so...)

George Conklin
03-26-2014, 9:28 AM
Thank you all for your kind responses:)

Jason Ritchie
03-26-2014, 4:21 PM
For me it has changed my turning drastically. Part of my issue was getting a consistent grind and the other issue was getting my tools sharp enough. You don't need a CBN wheel probably to get a consistent grind but I'm sure it helps. I was having to adjust my V-Arm after every couple sharpenings because the crappy Harbor Freight wheel was shedding so much material between sharpening and dressing. It was a constant battle. I think my case represents the the extreme as I came from a poor sharpening setup and went to the ultimate setup. I have dealt with tear out and rough cuts for years and had to so much sanding to get a decent finish. I always had to start with 60 grit to remove the tearout. I have done 4 bowls since my sharpening makeover and was blown away at how sharp the tools were. I was able to do a shear cut successfully for the first time to remove tear out. It was like magic really. I'm now kicking myself for not doing this sooner. I just re-sharpened my skew chisels and set them aside for honing but reached for one on a project before I got the chance and it cut just like I had honed it! Amazing I tell you. If anyone lives in my area here in NC and wants to see the CBN wheel in person you are always welcome in my shop. Bring your tools and see for yourself.

J.D.Redwine
03-26-2014, 4:46 PM
Will the next best thing be laser sharpeners?

robert baccus
03-27-2014, 12:11 AM
I hone with diamonds.