Elm for turning? Belt sander for sharpening?

Re: Elm for turning? Belt sander for sharpening?

Dinyar Chavda

>Re stationary sander---check out http://www.hdv.net/ and go to the section where Herm talks about using a belt sander to sharpen all his tools. Lots of other good info on his site, too.

Dinyar

Re: reeding

Ken Grunke

>Elm is great for turning, needs sharp tools. Can also be very pretty. Grab it!

I use a belt sander for skews and parting tools, but prefer a wheel grinder for gouges because with the concave bevel it's easier to hone between grindings.

Just make sure the belt moves AWAY from the tool, not into it.

misplaced subject!

Ken Grunke

>Sheesh!

I didn't notice that a subject from a previous post I made days ago had been placed in the subject box. Something to watch out for in the future!

Re: Belt sander for sharpening? (long) *LINK*

Brad Vietje

>I'm a big fan of both ! Elm is a beautiful wood, and sanding belts (inverted, mind you -- this is absolutely essential) are my absolute favorite way to sharpen. But controversy abounds ....

I occasionaly chime in with unconventional sharpening views, and ask people to think outside the box a bit (well, inside the bowl, actually), and even to look at a sharpening system that uses an inverted 4" belt sander with a buffing wheel for de-burring or honing (below).

In talking with Alan Lacer, he says the principal reason to put a hollow grind on a skew is so it can be easily honed by hand, and the hone will have two points on which to sit for proper maintenance of the bevel geometry. Flat bevels will work just as well, but aren't as good for honing by hand, as they are likely to get rounded into a convex bevel. (Of course, as you hone more and more, you are developing a very small flat bevel just behind the cutting edge.)

Here's the controversial part: I posit that you don't ever need to hone a skew or gouge if you can get a very keen tool with a sand & buff system that uses a fine belt. This system will produce just as fine an edge as a honed edge, but a flat bevel. Most people hone their tools, in my view, to save the tool steel that they don't want to grind away, because honing can maintain an edge without removing very much metal -- fair enough, and certainly true. I still maintain that if your sharpening system removes the absolute minimum tool steel, and you get a very keen edge, you just don't need to hone at all, except to put a burr on a scraper, or a similar reason. The facts are this: unless you hit screws or gravel, the diference between a sharp tool and a dull tool is less than half a thousandth of an inch (0.0005"). If you can consistantly sharpen and hone a tool by removing no more than this, you can sharpen that tool 2000 times for every inch of tool lost.

If you sharpen with an inverted sanding belt, you can put a buffing wheel on the same shaft that drives the belt (both travel away from you and the edge), charge it with tripoli or emory, and hone the tool in less than a second. The entire process of sharpening and honing a skew is 5 to 7 seconds, once the system is set for your bevel angles, and tool length. A curved, or radiused skew is no different -- it is rocked against the belt, producing a perfect, single facet bevel every time, in seconds. In my experience, many people make a mess of putting a hollow grind on a curved skew, if you look real close. The concavity just isn't consistant from one point on the edge to another, and ends up being different every time -- an unpredictable tool.

I'll attempt to post a link to a site with a sand-buff system I like a lot. I have no financial interest in this fellow's sales. I have used this system, borrowed this system, and demonstrated it in Albany a few months ago. I think it is simply the easiest and fastest way to take the stress out of sharpening that I have ever seen. He sells these systems for about $ 350.00, or $ 375 postpaid, and you can even make your own adaptation with a little inginuity, as I have.

We can go round and round about the suitability of convex, flat, or concave bevels, and no doubt, the opinions will fly on that topic, which deserves to be debated on its own merits.

Safe Spinning,

Brad Vietje

Thetford, VT


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