How To Turn Plastics - RIDGID WL1200 Owner's Manual

How to Use Your RIDGID Wood Lathe (continued)

How to Turn Plastics

Types Of Plastics
There are two general groups of plastics. The first in-
cludes all phenol plastics molded under heat and pres-
sure. Bakelite and Formica are examples. In the second
are all catalyst setting plastics of various bases sold under
such trade names as Lucite, Catalin, Cast Bakelite, Marb-
lette, Tenite and Trafford. Those in the second group are
most generally used for craftwork. They are easy to turn,
being a little harder than wood but much softer than any
of the soft metals.
Mounting The Work
Rods can be mounted between centers, using wood
mounting centers. When the spur center is used, slots
should be sawed across the work.
Use Of Wood Turning Chisels
Standard wood turning chisels are excellent for turning
plastics by means of scraping methods. The tool rest
should be slightly below center and the chisel handle
should be held a little higher than the cutting edge to give
a negative rake. Scraping tools should be used. The area
contacted by the tool should be kept to a minimum. A
large contact area, such as the full edge of the spear-point
chisel, will cause chatter and probable chipping.
Properly worked, the chip comes off in a continuous rib-
bon. In cold weather, plastic may become brittle and
should be tempered in warm water for about ten minutes
before turning.
Use Of Formed Tools For Production And Similar
Operations
When a number of identical pieces are to be produced, all
having a distinctive surface pattern, preformed tools will
speed the work and assure uniformity. Patterns like those
illustrated can be created by grinding thin (.020 to .010)
gauge aluminum strips. A holder, like the one shown, can
then be used to support any one of your prepared strips -
and guide it against the workpiece.
Polishing Plastics
Start with sanding. First use 150-grit dry paper to remove
tool marks; then finish off with 150-grit and 400-grit pa-
pers, in succession, used wet. Press lightly to avoid over-
heating and marring of the work. Buffing gives the final
polish, using the polishing compounds commonly sup-
plied for this purpose. Do not press too hard or hold wheel
at one spot too long - keep moving around - otherwise the
plastic might become heat marked.
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