A circular
Form Tool Holder
© Frank Ford 2006; Photos by FF

Here's a tool I've been wanting to make for a while now - a holder for circular form tools. The circular type form tool is often easier to make than a straight one, and it has the advantage of being resharpenable (is that a word?) almost indefinitely.

I had a sizeable piece of 1-1/2" water  hardening drill rod in my scrap drawer, so I chose that diameter for my first circular form tool, chucked the rod and turned a simple form that would give me two raised beads, by plunging with a round end 1/8" wide tool:

After parting off, here's my tool blank, with a 7/16" hole in its center:

On the mill, I cut the "tooth" in my new circular form tool. With the cut significantly below center, I'd be sure to have good clearance:

My form tool, after hardening - just starting to hone the cutting edge:

Now, for the holder -

Starting with a hunk of one inch thick cold rolled steel, I squared up a block and cut the dovetail to fit my Aloris tool post:

Drilled and tapped some holes, and stuck a 3/8 NF threaded rod in with some red Loctite:

Also from CRS, I made a little adjusable clamp to keep the circular tool from rotating under load:

Bolting it all together, here's the finished tool  holder with the tool in place:

There's no height adjustment nut, so I'll make one as my first project with this form tool.

Plunging the tool straight into some brass, I had two nice little beads in just a few seconds:


After "improving" the shape a bit, I used my little rope knurl to make those raised beads more grippy and interesting to look at:

Now my tool is actually complete:

I think I'll be using this form tool to make more knobs in the future:


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