I
was watching a sharpening video yesterday which proclaimed that you could lock
your arm while sharpening and maintain the same angle when you returned to the
next grit after changing paper.
I can sort of do this, but truthfully I can't do it perfectly. I have a
really hard time with maintaining my sharpening angle, and this is why I have
always resisted a flat bevel, preferring a hollow grind first.
So this is probably old hat to most of you, but I just came up with a way to
maintain the angle while sharpening. I am certain that somebody already
thought of this because there is nothing new under the sun. But it is
original thought for me.
My primary reason for trying this was because I REALLY have a hard time rolling
a gouge and maintain the angle. My carving tool bevels are pretty good, but not
as good as I would like them to be.
My first thought was to make my jigs out of metal because I could machine them
accurately. But I wanted to do prototype work in wood first to prove my
idea. It turns out that accuracy isn't needed. I'll stay with wood.
I am pretty well impressed with this little idea.
Take a look at the picture and read the captions under them.

I turned some pieces of wood to about 2 1/2" diameter and bored a small hole in
the center while it was still on the lathe. Then I cut off slices of the
cylinder to pieces about 3/4" thick. I radius one corner of each slice
while the big piece was still in the lathe. I bored larger holes in the
center in various pieces, and on one piece I cut a slot. I drilled and
tapped each piece for a set screw.
I had doubts about whether this would work because I thought it wouldn't be
accurate enough, and it wouldn't be secure enough. I was wrong on both
counts.

Small chisels work well in a bored hole, but big ones need a slot cut for them
to fit into. It should be obvious that this will work for gouges as well
as chisels. Because the jig is round, you simply roll the tool from side
to side while dragging it across the paper.

Here you can see how I hold the chisel while sharpening it. The angle
doesn't change when going from one grit of paper to another. My fingers
hold the chisel flat while sharpening.

So how do I get the angle set? Well, a piece of paper folded once across a
corner yields a 45 degree angle. If you fold it again you have a 22 1/2
degree angle. You can use this to set your angle for sharpening, or you
could cut yourself a piece of wood or metal in any angle you want. I set
each piece by eye, then leave the jig on the tool until all sharpening is done.

I made a couple of degree wedges to aid in setting the jigs. This is one
of my gouges which just got sharpened, and it is amazingly sharp!