How sharp is sharp enough?

[Ken S]

Oof, I don't know about that.  If a knife is really dull, or the angle is slightly different, it takes a while to get a burr using just the fine-graded stone.  Heck, even the coarse-graded stone can take a long time if you don't put some muscle behind it.

I would put those knives in the very dull and the damaged category. (Changing the bevel angle of a knife or tool takes a surprising amount of grinding.) By all means, start with the coarse side of the stone grader then.
Standard Tormek technique includes "don't be afraid to really lean on it" with the SG.

Ken

[cbwx34]

Looking back at our longstanding favorite knife sharpening video by Jeff Farris, Jeff generally used his SG-250 graded fine. He didn't normally use the stone grader for knives. Unless a knife is damaged or very dull, using the stone grader is not necessary.

Yes, the SG will gradually decrease in diameter. The key word is gradually.

You may remove the grinding wheel if you choose to. It is not necessary.

Ken

Always liked this video where Jeff demo'd sharpening a chisel after he "beat it up"...

https://vimeo.com/168186177

I remembered this video too, this a.m. (The 30,000 knives video)...

https://www.youtube.com/watch?v=8zQDmQ_n7wg

Amazing what you can do with stock equipment.

[Ken S]

Good post, CB.

The real "secret sauce" is skill.

Ken

[3D Anvil]

It's skill, but at a certain point skill is limited by physics, which is why Wootz was primarily using half-speed grinders with CBN wheels for his bulk sharpening business, and why most of the people I see using Tormeks for commercial sharpening seem to supplement them with additional equipment. 

[Ken S]

Good point. I started experimenting with Norton 3X 46 and 80 grit wheels several years ago. In my opinion, Tormek has never made a true coarse wheel. I realize these wheels fall outside of the Tormek philosophy; however, I want to be able to grind faster while still having the water cooled, dust and spark free Tormek environment. I found that the 3X wheels let me do that. They are not as fast cutting as a half speed grinder. They are considerably faster than the SG. They are only available in 8". They only cost around $60 US. For my small volume needs, they fill the bill at very low cost. They work as well as any Tormek wheel worn to 200mm.
Similar wheels are available in 10" diameter. They do the job, although I do not expect them to have Tormek quality.

Wootz built up a very good trade. He could command premium prices for premium work. Sydney is a major city with meat packing plants. His clientele included custom knife makers who recognized the quality of his work enough to contract him to sharper new knives. If that is the kind of sharpening business you desire, Wootz left you good guidance.

Ken

[3D Anvil]

I didn't know him, sadly, but Wootz produced some amazingly informative research.  He seemed to have a two-track business where he used the grinders for bulk sharpening (meat processing plants), but he also had high-end business which was more Tormek-focused, because the Tormek is gentler and ultimately produced even better results.

I've ordered a 160 grit CBN wheel from SchliefJunkies which should arrive next week.  Also ordered their shaft extender for running the wheel on the opposite side.  Their prices are quite competitive, even with the shipping from Germany.  The nice thing about their wheels is that you can run them wet without any corrosion inhibitor.  Or of course you can run them dry. 

I'm thinking about Mickey Mousing some kind of jig on the FVB to place a powerful magnet above the wheel to pick up the metal dust.  I've done something similar with the KO belt grinder and it works surprisingly well.  We'll see! 

The ones I have are similar to these, and they are incredibly strong.
https://smile.amazon.com/Neodymium-Double-Sided-Adhesive-Permanent-Scientific/dp/B089D33ZL2/ref=sr_1_3?crid=2C6SYTOP6VUWW&keywords=magnets&qid=1652805375&sprefix=magnets%2Caps%2C102&sr=8-3

[Ken S]

The T1 and T2 use this kind of magnet. It works well. In "the old days" (before the Advanced Water Trough with a built in magnet), we used to tape or glue disk magnets to the outside of our water troughs. A good grade of electrical tape will hold the magnet for years. I still use a taped magnet on my T4. I used one on my pre AWT T7 before I upgraded to the AWT.

Ken

[3D Anvil]

Cool, I've reinvented the wheel again.