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Wild_Bill Wild_Bill is offline
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Default Sawing polycaprolactone (Shapelock, Instamorph, FriendlyPlastic etc)

My guess (precisely accurate definition) would be to try a bow saw, the kind
of blade with huge gullets between very long teeth, used to cut/trim
wet/green tree branches.
I wouldn't expect the surface finish to be pretty, but you may be able to
smooth the cut surfaces with a warm, flat spatula or similar item.

There are most likely different qualities of bow saw blades, so a
cheap/Chinese one from a discount or camping source may not be the best
indicator of the particular type of blade. The ones I've used have been the
cheap type, and they do work fairly well on green wood.. but then green wood
is generally wet.

The cutting action apparently needs to be very slow to avoid heating the
poly material.
You may need a cutting lubricant since a wide surface area of blade is in
contact with both sides of the material. I'd avoid most hydrocarbon/oil
liquids (not knowing what might affect the poly) and try a liquid soap,
possibly thinned with water.

I don't know about the cutting of this particular product (maybe molding the
parts would be easier), but with most plastics, the (heat) welding that
takes place behind/after the cutter or blade is generally a problem, as the
warm plastic essentially welds back together.

--
WB
..........


wrote in message
...
The would belong on rec.crafts.plasticworking if there were such a
place... but hopefully this is close enough.

I'm trying to figure out how to saw through a 3 inch diameter solid
piece of tooling that I formed from polycaprolactone - re-usable beads
of plastic that soften in hot water then can be putty-knifed to
desired shapes then allowed to cool.

As expected for a low-temperature thermoplastic, it's pretty gummy and
likes to trap sawblades. I'm not getting much actual "chip" removal
with either a woodcutting hand miter saw or a hacksaw.

Contemplating either trying to find a cable saw I think I've seen
intended for pvc pipe, or small bow saw with offset teeth of the sort
used to cut a christmas tree, or just trying to rig up something with
a hot wire and melt my way through. The cut needs to be somewhat
regular so I can re-assemble the two halves with screws and shims in
the kerf for use, but it doesn't have to be perfectly planar.

Any suggestions?