Messages

I have been mulling over TGBTO's comments on convexing. In my opinion, his ideas seem more applicable to the professional than to the home axe user. Just after sixteen minutes into the online class, Sebastien makes an interesting comment. He states that when he wants to use his axes for splitting instead of convexing the edge, he just makes the angle broader. We have seen this before when users were concerned about hollow grinding. To counteract the hollowing effect, they would just add three degrees to the bevel angle. With his axes, adding a few degrees to the bevel angle is not really the same as convexing; however, for occasional home and general use, it seems an adequate substitute.

Ken

Good thoughts, Rich and Rick.

I hope to test for the practical limits of grit changing. The stone grader goes back to the days when the SG-250 was the only wheel available. I have long felt that the 220 and 1000 numbers were arbitrary and certainly not "digital" (either/or).

I purchased six diamond plates with grit ratings from 80 to 2000 from Amazon. The last plate finally arrived today. A logical place to start seems to be with the scratch pattern of the fine side of the stone grader on the bevel of one of my test chisels, what Tormek calls "1000 grit". I have no way of accurately testing grit number, nor do I especially care. The Tormek method of using the fine side of the stone grader will be my
designated fine grit.

Using Wootz' three times the diamond grit to determine the stone grit formula, I will start with one of the middle grit plates and determine which plate approximates the stone grader "1000 grit". Then I progress one at a time through the finer grits. I expect to reach a point where a finer grit no longer produces a finer grit on the grinding wheel. The finest diamond wheel which produces a grit change on the grinding wheel will become the fine grit limit with the SG wheel.

If my 2000 grit diamond plate produces any change in fineness of the grinding wheel, I will order a 3000 grit diamond plate. (After I ordered my diamond plates, I became aware of the 3000 grit plates.)

I will then perform these same fine grit limit tests with the SB and SJ wheels.

I would like to make two points clear: First, I do not consider this level of attention practical for most knives. I think it might possibly make sense for one's best clients and knives. Atthis point, it is only a possibility, not a certainty. Second, I have no intention of being critical of Tormek for sticking with the stone grader. Tormek has knowledge and experience leagues beyond mine.

This initial test will give me an idea if further tests are practical. My shop time is very limited. Please be patient. I will post results when they are available.

Ken

Tgbto,

I respect your thoughts as an experienced. However, with the AX-40, I don't see where any of us have enough actual work time with it to offer more than initial impressions. I will look forward to reading your thoughts after hours of use. I will also anticipate your thoughts on flat grinding with the AX-40.

Ken

Rick,

I'm glad you are back in your new shop!

Ken

Rick,

And here I thought dental floss made my knives sharper   

Ken

I just watched the new online class. I am impressed with the new AX-40 axe jig!
Once again, the Tormek Development Team has cleverly built on innovations from previous other jigs to build a better product. Well done!

Ken

Baz,

I have a young friend who is presently studying to be a welder. I was particularly impressed by your comment that your very smooth sharpening technique came from having previously been a welder. (I noticed the same smooth control with Wootz.)
Your comment struck a chord with me; I think about it whenever I sharpen knives now.

Ken

I believe the dental floss clips may have originally been an influence on the development of the BESS clips. However, it seems to me that flossing and BESS measuring have different product requirements. Dental floss, being used in the mouth, must have stringent sanitation requirements. BESS test filament must have stringent breaking control. Consistent breaking pressure control for dental floss and test filament sanitation seem like secondary priorities to me.
I can see possibility of dental clips as a replacement with the economy tester with 25 gram accuracy. That should provide enough accuracy to detect a burr for home use. Industrial users might require greater accuracy.

One of the skills machinists acquire through experience is sophisticated, consistent touch. I'm sure experienced BESS users like Wootz developed a similar consistency with filament tension and testing technique.

Ken

In case anyone is having difficulty finding the new online class, here is a link:

https://www.youtube.com/live/5cll8S5zx8E?si=2NQs8P00naKRFO_6

Ken

Thank you for posting, Hugo. We are eagerly awaiting online class #25 tomorrow
(Sept 17 at 9:30 EST).

I hope you can provide some history about the present SVA-170 jig, such as when it was first introduced and if it was the first Tormek Ax jig.

Ken

Rich,

Thinking about how to do these tests, I plan to use my dozen identical 3/4" Irwin Blue Chip chisels. The chisel bevels are much larger and easily to see than knife bevels. For closer inspection, I can use my machinist's loupe. I can use masking tape on the handles to identify which chisel is which grit. As I already have these chisels, no extra cost will be involved.

My gut feeling is that trying to use half a dozen different grits may prove cumbersome. One or possibly two middle grits may prove useful.

I presently have an unusual amount of family commitments, so results may take a while to complete. In the meantime, I welcome comments and test results from other members.

Ken

Much praise has been posted about the benefits of superabrasive wheels, both diamond and CBN. The diameters do not decrease with wear and they never need truing. While these are indeed formidable advantages, the praise chorus often overlooks a notable constraint. These marvelous wheels are single grit. Standard advice given to new users is often to purchase three diamond wheels or four or more CBN wheels. We are starting to see conflicting advice given to new users who want to purchase only one wheel due to budgetary constraints. Purchasing a set of superabrasive wheels can easily double the investment in a T8. What to do?

Our late very innovative member, Wootz (Vadim of Knife Grinders), did the preliminary work on a solution. Tragically, his death cut short the development of his ideas. One of his most promising ideas was the use of diamond plates for grading the SG and SB grinding wheels. While still not universally known or accepted, we now know that the concept of using the stone grader to change the grit from 220 to 1000 (only) was an oversimplification. For years, the concept of "600 grit" has been gradually entering the conversation. "600 grit" is a grit somewhere between 220 and 1000, a medium grit somewhere between 220 and 1000, as opposed to an exact number.

Wootz also introduced the idea that using a 1000 grit diamond plate to grade the SG could produce a grit similar to 1500 grit.  Wootz also introduced using the 80 grit diamond plate to set the SB wheel to coarse without having some grains standing proud. Wootz left us some interesting ares to further develop.

I do not mean to minimize the importance of the stone grader. For the many years when the SG was the only available grinding wheel, the stone grader provided a way for the Super Grind (SG wheel) to also grind like the finer (smoother finish) discontinued natural sandstone grinding wheel.

My question for my fellow forum members is have we explored the limits of the grading potential of the SG and SB wheels? If, as Wootz said, a 1000 grit diamond plate will produce 1500 grit with the SG, will a 2000 grit plate produce an even finer grit? Or, is a 1000 grit the maximum for making the SG finer? What about varying grits with the SB or intermediate grits with either the SG or SB?

I recently ordered half a dozen diamond plates in various grits from 80 to 2000 from Amazon. At around $10 US each, they were not expensive. Three or four would provide the average Tormek home user with plenty of versatility at a fraction of the cost of a set of superabrasive wheels.

I welcome your thoughts.

Ken

Good point, John. What I do for the forum. 

Ken

I once attempted to watch a 42 minute youtube about a supposedly already reasonably sharp knife being "sharpened" with only a 4000 grit SJ-250. It was painful to watch. I gave up halfway through. Unlike the SJ, (a polishing stone), the DF diamond wheel is a sharpening wheel designed to remove metal. It is slower than the coarser DC wheel, but it is also smoother cutting. It is plenty fast for most sharpening, and rewards the patient sharpener with smoother edges and longer tool life. While the initial sharpening may take longer, a careful user will only experience this once.

Ken

Hi, HL.

No design flaws, just innovation changes. My present T7 is what I call a later one, from sometime in 2011. My original T7 was stolen during a burglary while I was moving. I had purchased it in August of 2009. I would call it one of the earlier T7s. I believe all T7s had stainless steel main shafts, a major improvement.

Between 2009 and 2011, Tormek changed to the EZYlock; the AWT advanced water trough (a larger water trough); and the annoying safety switch.

Since you are "the previous owner", I would not be concerned about past usage. I would suggest you purchase a new TT-50 truing tool. I would also suggest regreasing the nylon bushings (good housekeeping).

Ken