Old vs New Formula Difference...

[Dutchman]

I don't consider it "hijacked"... I consider it an alternative.   Even for the "ordinary user" it's an alternative way for setting the USB... not really a better or worse one (nor any harder).

In my opinion it is hijacked. The formulas are used without any reference to how they are derived. How can you expect that it gives some confidence?

[Jan]

I agree with CB, that the calculator programs are good alternatives for setting the desired bevel angle via the USB height. It is important that they are offered for free, so following St. Paul we can "test everything and hold fast what is good" (1 Thes 5:21). 

Mr. Ton is right in that the authorship of formulas and approaches must be referenced when possible. 

Jan

[cbwx34]

In my opinion it is hijacked. The formulas are used without any reference to how they are derived. How can you expect that it gives some confidence?

Hopefully in actual use.

I do try and reference "where it came from"... admittedly, it got left out of this thread.  But in the long term... I'd like to see any one of these methods get adopted "beyond the forum"... where its used for the results obtained... without necessarily knowing the "behind the scenes" math.

But hopefully, credit is given where appropriate.   

[Ken S]

I think we are overlooking a couple very important things:

1) The CADD drawings may bring to light a slight inaccuracy. I do not deny this, however, I remember when Jan first posted this. Jan certainly has the math expertise to discover this. He also has the wisdom to realize that the error was not significant. What I do feel is significant is the probably increase in accuracy in eliminating the need for measuring with the Anglemaster. Measuring brings up the possibility of both human and tool error. When I applied Ton's tables to the kenjig, I deliberately eliminated the need for individual measurements, including with the Anglemaster. Any multiple measurements with a graduated rule, caliper, or protractor device such as the Anglemaster are error prone. By good measurement practice, expecting accurate measurements would require graduations considerably finer than one degree.

By comparison, the kenjig is designed to work like a gage block. Gage blocks can be made of hardened steel or carbide, designed to measure millionths of an inch. The humble kenjig is certainly nowhere near that accurate. It is, however, consistent. I have no way to test this, however, I believe that the simple, non measuring aspects of a kenjig should minimize any inaccuracy.

2) I think it is important to realize that in the same booklet as the grinding angle tables (in 2014) Ton also sounded the alarm about thick grinding angles. In both ateas, he was a forum pioneer. I am pleased to see he is finally starting to get the recognition he deserves.

Thanks, Ton.

Ken