Home-grown spring loaded tool holder, using linear bearings?
 

Awl--

Sort of like a tension/compression tap holder, but better, if I can swing
it.

Picture a 1" tool holder of sorts, w/ a 1/2 x 1 bushing, w/ a 1/2" shaft in
the bushing, which I want to be able to slide in and out of the bushing.
Then, picture two ball bearing raceways, one on either end of the bushing,
except instead of allowing the shaft to rotate, it would allow the shaft to
slide in and out, like a linear bearing.

The bushing would actually have a few thou clearance on the shaft, and be
broached for a key, to keep the shaft from rotating, but still slidable on
the bearings.

What type of bearing would this be? It's not strictly linear, but two of
them spaced apart would perform the same function on a shaft. Any sources?

This set up, in a cat40 tool holder, w/ a compression spring, would allow a
pretty nice spring-loaded chuck for pressure-type c-sinking, engraving, etc.

TIA!
----------------------------
Mr. P.V.'d
formerly Droll Troll

Sounds a lot like the Glenn Wilson design published in the December '93 PIM. His
was R8, though, and set up for square letter punches. Really nice design, I've
been planning to make it for about 10 years now.

If you quit using that hideous name I'd scan this and either post it or mail it
to you.

GWE

Proctologically Violated©® wrote:

Awl--

Sort of like a tension/compression tap holder, but better, if I can swing
it.

Picture a 1" tool holder of sorts, w/ a 1/2 x 1 bushing, w/ a 1/2" shaft in
the bushing, which I want to be able to slide in and out of the bushing.
Then, picture two ball bearing raceways, one on either end of the bushing,
except instead of allowing the shaft to rotate, it would allow the shaft to
slide in and out, like a linear bearing.

The bushing would actually have a few thou clearance on the shaft, and be
broached for a key, to keep the shaft from rotating, but still slidable on
the bearings.

What type of bearing would this be? It's not strictly linear, but two of
them spaced apart would perform the same function on a shaft. Any sources?

This set up, in a cat40 tool holder, w/ a compression spring, would allow a
pretty nice spring-loaded chuck for pressure-type c-sinking, engraving, etc.

TIA!
----------------------------
Mr. P.V.'d
formerly Droll Troll

I'm not totally sure I understand your description, but are you looking
for a likea ball-spline? They're like a round-way ball bushing, but
the cross-section of the shaft is usually something of a triangular
shape. They allow the bushing to move along the shaft, but
simutaneously transmit torque. Very pricey though.

http://www.thomsonindustries.com/Systems.htm