JeffSimmons wrote:


If I measured/calculated right, this should only be about 1/3 deg. difference, not the 1+ deg. difference you said you're getting.

One other thing you could try, is to mount a knife, measure the angle, then turn the WE around and remount the knife,,, see if the error "switches sides", or stays the same. This will help show if the error is in the WE or not. I'd try this with a knife with flat sides, so you're less likely to introduce a mounting error.

cbw

Confirmed your math. I did the trig with measurements that included a knife mounted where the bevel was 4.25 inches from the base of clamps.

Tan = Opp/Adj where the measurements on the left side were 4.25\2.09 and the measurements on the right side were 4.25/2.06

Left = 2.0334
Right = 2.0631

Calculated inverse tangent to get the missing angle (at the bevel) and got:

Left = 63.82
Right = 64.14

This is about 1/3 of a degree difference. Not sure where the other 2/3 +/- of a degree is coming from. Wherever it is, it's consistent...

Maybe I am just consistently doing the wrong thing!

Interesting, you guys have another player here working on a SC vise.

JeffSimmons wrote:


well, that is nice math but... can you measure the angles and tell us what they really are on this blade? a goniometer measurement would be best, but you can estimate with an angle cube and the WE rods themselves (no paddles installed), or a careful use of a straight edge, this would be helpful

.. this is perhaps not an angle issue or an issue with the WE, but is a good example of blade asymmetry as a result of sharpening technique. See Ken S excellent vid that discusses this in detail :

The key concept of this video is that one can adjust blade asymmetry simply by adjusting how much you grind on either side of the knife and it is completely unnecessary to change angles when adjusting asymmetry. Stated another way, you can have extreme blade asymmetry while at the same time having exact and identical angles everywhere and on both sides of a blade.

OK, this popped into my head driving. So haven't thought it out too far but.....

If its technique, spin the WEPS around and mount the knife from the back, so right is left and left is right and sharpen a knife. YOu know, mounted like normal just the WEPS backwards.

If its your left hand technique or whatever, should show it no?

Like I said, just popped into my head, but then again, my head is firmly up my rear in most cases so take this idea with a grain of salt

Well, Dan did make the point that grinding on one side more that the other can make for a larger bevel even with both sides at the same angle. So you can match bevel widths by grinding for a longer time on the side that is shortest.

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Ken