Thoughts on the Diamond Wheels vs. Traditional Grindstones

[RichColvin]

Hi there,

I'm new to this community.

My plane irons and chisels are all A2 steel.  The plane irons some 4.5mm thick.  Obviously repairing nicks in these blades means that a lot of metal needs to be removed.  I've tried the Blackstone but, whilst a fine stone, takes forever to grind away A2.

My question is, will the new Diamond Stones from tormec be up to the job? Never cheap in the first place.  More expensive still when I bought a Blackstone wheel. These diamond ones???

Charles,-

I agree with Rick.  The DC250 is much faster for reshaping than the SB-250. 

Kind regards,
Rich

[Ken S]

Just a quick trip back to wheel dimensions: I have one of the non Tormek wheels with a 254mm width and slightly more than 50mm thickness. (It crowded my original T7 water trough.) I do not think it was manufactured to metric dimensions. My guess is that someone unfamiliar with the Tormek living in a country using Imperial dimensions ordered 10" x 2" wheels.

Back on topic: I agree with Rick and Rich that the DC-250 is faster for reshaping than the SB-250. The DC cuts continuously with a satisfying grinding sound and feel. I find it cuts faster in the vertical position. Be sure to use light grinding pressure to protect the wheel.

I am not the person to ask about the SB. People I respect have gotten good results using it. I have never gotten it to well, something I attribute to operator error and lack of good instruction from Tormek.

The DC does not cut as fast as a high speed grinder. It is up to the job if one has a bit of patience. I like the DC.

Ken

[RickKrung]

...snip...
I agree with Rick.  The DC250 is much faster for reshaping than the SB-250. 
...snip...

I do agree with Rich, the Tormek coarse diamond wheel (DC-250) is faster than the Tormek Blackstone (SB-250). 

However, I did not say this and the point of my post was that a much cheaper and faster yet alternative to the DC-250 is a Norton 3X grind stone.  My statement was (emphasis added) :

...snip...
I have found the Tormek coarse diamond wheel (DC250) wanting when a lot of steel needs to be removed.  When I am faced with needing to remove a lot of metal, I go to a more traditional grindstone, the Norton 3X, which is ceramic alumina designed for heavy metal removal. ...snip...

For $60 plus shipping and some work to adapt it (drill out some PVC pipe), you can have a wheel that removes metal faster than the DC-250. 

I received both the 64 and 80 grit Norton 3x wheels from Ken S., but I screwed up when I made the bushings.  Somehow, the steel I made the bushing from for the 64 grit wheel was NOT stainless, so it rusts, so I don't use it.  The bushing for the 80 grit wheel IS stainless, so that is the one I use and even it is faster than the DC-250.

Rick

[RickKrung]

...snip...
The DC does not cut as fast as a high speed grinder. It is up to the job if one has a bit of patience. I like the DC.

Ken

Ken's and my posts crossed in the wires.  Again, I do agree the DC cuts faster than the SB.  But... again...  The Norton 3X wheels cut faster yet. 

And to clarify something that may not need it , my use of the Norton wheels is not on a high speed grinder.  Rather, they have been adapted for use on the Tormek, extremely slow speed (by comparison) and wet. 

Rick

[Ken S]

...snip...
The DC does not cut as fast as a high speed grinder. It is up to the job if one has a bit of patience. I like the DC.

Ken

Ken's and my posts crossed in the wires.  Again, I do agree the DC cuts faster than the SB.  But... again...  The Norton 3X wheels cut faster yet. 

I agree totally with Rick. The Norton 3X wheels are the fastest cutting wheels I have ever used on my Tormek.

I started working with the 3X wheels because I was looking for a true coarse grinding wheel for the Tormek. I like the concept of the SG wheel, which can be varied from coarser to finer with the stone grader. It makes a very practical one wheel machine and has been my go to wheel for sharpening. 220 grit is not coarse. 46 grit, as in the 3X, is coarse. It allows fast cutting while preserving the water cooled, dust and spark free Tormek environment.Tormek has never made a coarse wheel. The DWC-200 and DC-200 are Tormek's wheels which come closest to being coarse wheels. They are designed for the Tormek, and work well with the Tormek. I should note that Tormek only recommends the DC-200 for dry use, and only with the T2. (I have used it dry with the T4 very successfully.)

I have a standard test for grinding wheels. I place a metal lathe cutting bit in my square edge jig set for thirty degrees and grind for a timed five minutes. The amount of metal removed tells the story. I ground through the entire edge of the metal lathe bit in five minutes with the 3X 80 grit. I ground the same amount with the 46 grit in four minutes. Regretfully, I did not keep good records. Both the diamond and CBN wheels performed respectably, but not as well as the 3X. The SG performance was not too bad. It outperformed the SB.

My conclusion: My first choice for a totally compatable coarse wheel is the DC-250. It does not cut as fast as the 3X. It is 250mm, an exact, direct for for the Tormek, and designed to work wet.

Based solely on quick cutting, my first choice is the 46 grit Norton 3X. It has some drawbacks. It is only available in 8" (200mm) diameter. The wheel will eventually wear with use and need occasional truing/dressing. Rick, with his machinist background, made a proper bushing to mount the wheel. For me, since it is a coarse wheel, I was content to roughly ream out a piece of plastic pipe. Not perfect, but adequate. The 46 grit 3X wheel gives a lot of fire power for fifty dollars. It will work on either size Tormek.

Ken

And to clarify something that may not need it , my use of the Norton wheels is not on a high speed grinder.  Rather, they have been adapted for use on the Tormek, extremely slow speed (by comparison) and wet. 

Rick

[Ken S]

Rick,

Many thanks for your information.  I left my Karl Holtey plane irons in store for two years and the A2 suffered very badly.  So much so that I decided to order two new blades for my 98s. What an expensive mistake.  Fortunately the planes are made in stainless steel.

I have been wondering why your A2 Holtey blades chipped. Have you been sharpening them at the recommended 30° bevel angle for A2?

The 98 is a smoothing plane. As such, your shavings should be very fine, around .001" thick. The smoothing plane is only used anter the jack plane does the heavy lifting and the jointer makes the board level. The role of the smoother is like the role of the 8000 grit polishing stone in sharpening. If used correctly, I don't understand the blade chipping.

Please do not midinterpret this post as criticizing you. My only desire is to help solve your problem.

Ken

ps here is a link to the Holtey 98 smooth plane.

http://www.holteyplanes.com/planes_No98.html