Sharpening Demystified..........

Stuart Ablett

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Location
Tokyo Japan
Recently at a local club workshop, one of the members brought his copy of the American Woodturner Magazine, Vol 21, No.4 Winter 2006.

There is an article by Kirk DeHeer called "Sharpening Demystified"

The fellow that brought the magazine to the meeting, asked me to read it and translate it for him, I gave it my best shot, and then we discussed the article.

It really opened my eyes to how the jig that most of us use to sharpen bowl gouges really works.

I do not have a copy of the article, nor would it be right to copy it here if I did, but I can tell you, if you can find it somewhere read it, it has a ton of info.

I did make copious notes :D

My big problem is that the wings of the grind on the bowl gouges are way too steep, way too straight, and way too long.

With this new found understanding, I've been able to cure this! :thumb:

I'll post some more pics later, I ran out of time this AM, as I had to go to the bank for the LOML.

Here is a before and after shot.......

before_after.jpg

I think you can see that the after pic shows a much better grind on the gouge, which I hope will be a LOT easier to control.

I've still got to refine the technique, but this is WAY better than what I was doing.

In a nutshell, the Mr. DeHeer says that we have to change our thinking, we need to have the angle on the nose of the tool, follow around onto the wings, with the way most of us use our jigs, you cannot get this to happen. the angle on the wing of the tool, is NOT set by the angle on the leg of the jig. The important thing is the distance from the wheel that the V-pocket on the arm of the tool rest is, combined with the stick out of the tool from the jig, and the jig's leg angle. (I can see pics are going to me needed :eek:) This is not easy to explain, or understand I bet.

Well, I'll get some more pics later this evening.

Anyway, the leg angle is set at only 23 degrees.

bad_drawing.jpg

Sorry, I got to run, I'll get back to this later.

New grinding set up below.

new_grinding_set-up.jpg
 
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