best diamond wheel grit for woodturning

[blackhawk]

I am looking at purchasing one of the diamond wheels for my woodturning tools, mainly bowl gouges and scrapers.  I am leaning toward the coarse (360 grit) stone.  This is because my woodturning mentor uses CBN wheels on his 1750rpm bench grinder.  He uses a 220 grit CBN wheel for his final sharpening and his tools feel razor sharp off the 220 grit wheel.  He has tried higher grit CBN wheels, but likes the 220 grit.

Does anyone have any experience with the different diamond wheel grits for bowl gouges and scrapers?

[AKMike]

Here is a tip from Glenn Lucas's July 2017 e-zine:

"The new Tormek diamond wheels go on sale this month. They are offering three wheels which are coarse 360 grit, fine 600 grit, and extra fine 1200 grit. Having tried and tested each of them, if I was to choose one for every day fine sharpening of my woodturning tools, it would be the 1200 grit. Make sure your jig settings are accurate so that you hit the right spot every time.

It achieves an incredible edge in seconds. I recommend using it with water and their anti-corrosion additive, this helps keep the wheel clean and prevent magnetic filings sticking to the tool edge. The wheels stay flat with no dressing and are a dream to use. I have been using the 600 grit for over one and a half years  with superb results and was keen to try the 1200 grit.  If you have to reshape your tools then an additional purchase of the coarse wheel would be a good idea. It is quite effective at material removal.

Make sure to read the instructions as there are some great tips how to easily prolong the life of your investment."

Glenn is a world class woodturner, and was a beta tester of the diamond wheels for Tormek. I tried to find a link to that e-zine, but couldn't find it.

Glenn's website: https://glennlucaswoodturning.com

Glenn is also a Tormek Friend: https://www.tormek.com/usa/en/about-tormek/tormek-friends/

Mike

[Ken S]

Excellent post, Mike. I wonder if the common preference for stopping with a coarser wheel is a leftover from before diamond wheels became available. with uniform jig set up and faster cutting diamond wheels, sharpeningtimeis reduced. It is now easier to use sharper tools.

Ken

[AKMike]

Given how quick it is to resharpen turning tools with the Tormek, and how little metal is removed from the tool,  both Glenn Lucas and Nick Agar recommend frequent touch ups, so the 1200 grit diamond wheel works great for that. If you let your tools get very dull, or you reshape your tools often, then you're going to need a coarser wheel. If you do reshape often, it's probably cheaper in the long run to buy a second tool.

Mike

[blackhawk]

Mike - Do you use the 1200 grit diamond wheel?

[Ken S]

Another excellent post, Mike. I totally agree.

I like to imagine a two axis graph. The horizontal axis is tool use time. The vertical axis is percent of sharpness. The starting time is the full sharpness with the grinding wheel and honing wheel (if used).As the tool is used, the line moves to the right (with use) and down as the tool dulls. When the tool reaches a certain amount of dullness, and the tool is sharpened, the vertical axis returns to the original high point. If we take the average sharpness, the average sharpness will increase as we sharpen more frequently. Higher average sharpness translates to cleaner turning.

Jeff Farris also made the recommendation to purchase another tool already shaped instead of trying to reshape the original tool on the Tormek turning DVD. He also adds that in the possible case where you decide you prefer the original shape, there is no need to regrind.

Like Mike, I hold both Glenn Lucas and Nick Agar in high regard.

Ken

[AKMike]

Mike - Do you use the 1200 grit diamond wheel?

I have the 1200 grit wheel, and if I was turning as often as I would like to, I would definitely be using it. My local club brings in two expert turners each year and I always sign up for classes. (Stuart Batty and Sam Angelo this coming Spring - looking forward to it.) It seems that is when I get to do most of my turning for the year. I take my Tormek to the classes, but I use the SB stone graded fine for that, mostly so I don't have to educate the other class members on the proper use of the diamond wheels.The other class members mostly use the clubs' high speed grinders, but some enjoy trying out the Tormek and its jigs.

Mike

[Ken S]

I believe one reason for a general preference for high speed dry grinders may be because Tormek has only recently included fvaster cutting diamond wheels in the lineup. Even the SB blackstone has only been in the lineup for ten years, and Tormek has offered very limited instructions for it.

Ken

[Twisted Trees]

Said it before, but it is appropriate to repeat here... in woodturning you should sharpen often so you are only ever polishing and refining an already sharp tool, so fine is good... re profiling is tool-making not woodturning! for that a different approach is appropriate.

[Ken S]

Well stated and well worth repeating, TT. I remember chopping the dovetails for a class project Shaker candle box in a hand cut dovetails class. I could feel my chisel gradually becoming dull. As a turner, you can feel the same thing with your turning tools. I think that end user feeling is vital for a sharpener.

Ken

[blackhawk]

I have one other concern before purchasing the diamond wheel.  What if your tool rest is slightly out of square with the wheel?  With a stone wheel you can simply dress the wheel with the TT-50 and you are square to the tool rest.  Since you can't dress the diamond wheel, do you just have to live with the out of square condition? 

This wouldn't make much of a difference sharpening gouges, but definitely would affect wood chisels and plane irons.

[Ken S]

Just like any other Tormek product, I would return a diamond wheel which was out of square.

Ken

[blackhawk]

But, what if my shaft or universal support is out of square instead of the diamond wheel?

[Ken S]

I suggest you contact support (support@tormek.se). They are located atthe factory in Sweden where every new Tormek and every Tormek sent in for repair is tested. You will not find more experienced Tormek technicians than support.

Ken