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CBN grit

Bill Boehme - thanks! for your reply. Gives me some more to think about before replacing the wheel on the Tormek, and a little research to do on the diamond wheel.

Don’t get me wrong, I like the Tormek...but it mostly just gathers dust. “Messy” is in the eye of the beholder. To use my Tormek I need to get a container of water, add it to the tray (a few times as the wheel soaks it up), redress the wheel, sharpen my tool, empty out the water, and then clean the filings from the magnets I have in the bottom of the tray (guess I could just dump filings down the drain...but I don’t).

All of that is a bigger hassle than just turning on the other grinder and sharpening (dressing wheel a little - which now I won’t need to do with cbn) and vacuuming up filings.

I like the fact that water gathers filings and keeps from being airborne, but the hassle of water and slurry in the shop (slurry includes sawdust mixing in), along with the slow speed of using Tormek, means I only pull it out for a special need that I can’t do otherwise. I think a dry wheel that didn’t require honing would mean I use it much more. Still, need to let your comments ruminate a little while. Thanks for your thoughts.
 
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I don't understand your comment about the Tormek being messy. Could it be that you are overfilling the water tray? I don't keep the Tormek close to the lathe because shavings and dust in the water would be messy, but that is a self-created mess and not inherent in the machine.

I dislike the mess of the water tray. Mine gets this sort of mud in the bottom that needs to be washed out at the end of the day and for me just filling the water tray every time I use it is a pain.

however, when I use a skew a lot it is orthodox the effort. I have the stop wheel and it refreshes the skew edge nicely.
 
The price of the diamond wheels is essentially the same as the CBN wheels.

I recognize the comment was in the context of Tormek, but how do diamond wheels compare to CBN in general?

Are they more suitable for use with high carbon steel than are CBN? Do they last as long? Perform as well? Are they available for ordinary grinders? Cost? Downsides?
 
I saw Stuart Batty a year or so ago, and he commented that a CBN wheel was good for about 6 years for a production woodturner. I will agree with that. I had a set I used longer than that, maybe, and after a while they left a glass smooth finish on the tool, but it took some effort to get an edge. Glenn Lucas made a comment that he used his for about a year and then found them a good home. For sure, they cut very fast when brand new, and a 180 grit will take off metal as fast as a 120, or maybe even an 80 grit wheel. The diamond wheels for the Tormek should last forever. We don't see diamond grinding wheels for turning tools because the diamonds break down with the higher speeds which causes heat, and diamonds don't like that... If I ever get a diamond wheel for my Tormek, I will probably just use the honing compound rather than water. It dies seem to help keep my CBN wheels cleaner.

robo hippy
 
Don’t get me wrong, I like the Tormek...but it mostly just gathers dust. “Messy” is in the eye of the beholder. To use my Tormek I need to get a container of water, add it to the tray (a few times as the wheel soaks it up), redress the wheel, sharpen my tool, empty out the water, and then clean the filings from the magnets I have in the bottom of the tray (guess I could just dump filings down the drain...but I don’t).

I have my Tormek in my garage, not my shop so getting wood dust in the water is not an issue. I solved the problem of metal filings in the water by gluing a large super magnet on the outside bottom of the water trough with Goop which is good for sticking just about anything to anything else.

Tormek_magnet.jpg

Tormek later came out with their version that had a small magnet on the inside. I bought one of their water troughs, but I like my solution far better. To clean the metal dust and grit out of the trough I just lay it on the grass in the back yard and use the garden hose with a high pressure nozzle. I wouldn't want to dump it down the drain.
 
I recognize the comment was in the context of Tormek, but how do diamond wheels compare to CBN in general?

Are they more suitable for use with high carbon steel than are CBN? Do they last as long? Perform as well? Are they available for ordinary grinders? Cost? Downsides?

The diamond wheels are not suitable for use on regular dry grinders. The reason is that the diamonds start to wear down at temperatures above 700° F. But, at slow speed (Tormek speed is 90 RPM) and especially in water the diamond wheels are ideal. The diamond wheels are also able to resharpen tungsten carbide cutters.
 
I have a 180 and a 600 CBN wheel. Once I have the shape with 180, I use the 600 for touch up, removing a very small amount of metal. Works for me.
 
The diamond wheels are not suitable for use on regular dry grinders. The reason is that the diamonds start to wear down at temperatures above 700° F. But, at slow speed (Tormek speed is 90 RPM) and especially in water the diamond wheels are ideal. The diamond wheels are also able to resharpen tungsten carbide cutters.

Will not work on plastic tub but I have magnets in zip bag on the Wolverine. To clean just hold over trash and move the magnet inside the bag slightly.
 
Thanks for all the information. I think I will try a 600, less metal to end up on the floor. Also for you hollowing turners. I am looking to buy Trent Bosch tools etc and I notice the grinding of those little bits he rolls the tool up on its edge slightly to keep the radius. And I have seen other people use the radius CBN. What is your preferred grit and style of CBN wheel (square or radius) for these type of hollowing tools. I have never hollowed or should I say never did a hollow form biggest than a box.
 
What is your preferred grit and style of CBN wheel (square or radius) for these type of hollowing tools
You will probably get answers ranging from 60 to 800 grit :)

I prefer 180, which seems to be a good balance between being able to occasionally remove some metal, and getting a decent edge. I like the wheels (and their cost) from https://woodturnerswonders.com. If you're getting your first CBN wheel, I'd recommend the "4-in-one" design that has a radius edge, and a useful flat side (also get a set of the spherical washers). I sharpen my Trent Bosch hollowing tools on the radius edge. The flat is useful for flattening the top of a scraper or sharpening the side of a box scraper, etc.
 
Thanks Dave, I have 2 CBN wheels now I have been using 180 and 80 square. I’m thinking about a 600 and maybe a 180 radius.
 
I am not a fan of the radius edges. I like the full 1 1/2 inch width, and the square corners cause me no problems. I have heard that the radius edges are primarily for hollowing bits, and that they are an idea of Dave Ellsworth.

robo hippy
 
@Dean: Unless you have a specific need for those rounded edges, stick to square wheels. You will love every bit of the large, flat area when you sharpen gouges and scrapers.
Lars
 
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