The parting tool is used to cut off (part) the
wood at a certain point while it is still turning. It is also
used to size certain locations on the wood while it is turning.
You use a pair of calipers, pre-set to the
desired size, in one hand, and the parting tool in the other.
As you cut a groove deeper and deeper into the wood with the
parting tool, the caliper is also in the groove. As soon
as the caliper will slide onto the remaining wood, you know you
have cut deep enough.
This process is repeated at each location where
you want a size established. This is a great aid in turning. It
helps you keep track of the required various sizes at all the
various locations on your piece.
Making Parting Tool
After pricing a parting tool for wood turning, I decided to make
my own. I started with a high speed steel power hack saw blade. I
ground off the teeth of the blade and then cut it to tough shape
with a die grinder equipped with a cutoff wheel.
It is not necessary to worry about rounding over the edges of the
blade because you will relieve the cutting edge as shown below. This
will get you back to full blade thickness.
The bottom of the tool as shown goes against the tool rest.
Since this is a high speed steel blade the blue on the point is of
no concern. Bluing high speed steel does not have any effect on it.
When I grind the tang to shape I want the centerline of the handle
to be above the centerline of the blade. This causes the cutting
force to hold the blade straight while parting.
For a handle, I turned one similar to the Sorby handle. Most of
the home made tools I have seen have a handle similar to what you
would see on a pigsticker mortise chisel. Kind of square and wrapped
with duct tape. Not real attractive.
They think it gives better control. I find that a good looking
handle gives good control provided that you make the centerline of
the tang above tool center.
I drilled a 1/8” hole 3” deep in the end to start the tang in. Then
I heated the tang and shoved it in. I added a little CA glue to make
sure it doesn’t wiggle.
This is my finished parting tool. It works like a champ, and I
think it looks pretty good. The wood is silk oak.
the Old Millrat in
Tips from Old Millrat - James D. Thompson