On Sat, 16 Aug 2008 03:01:46 -0400, Wes wrote:
James Waldby wrote:

I used aluminum rather than CRS for the heater block, and 3/4" stainless
for the plunger. Drilled a hole through the block, then bored it out
to size on a lathe. Ended up with a sloppy fit (the bore might be as
much as .001" oversize) but the viscosity of the various common
thermoplastics I've molded with is high enough that leakage around the
plunger isn't much of a problem. Given the small amount of plastic
molding I do (a few dozen parts per year) it's not enough of a problem
at present to be worth fixing.

What temperature does this run at?

The block has 2 ea. 175W heaters, one on a 500-degree-F
controller, the other manually switched and only turned on
to bring the temperature up faster when starting from cold.
Molding small parts from cut-up plastic coathangers, I set
the controller for 450F, which IRRC may be 50F higher than
Gingery recommends. My molds heat up by conduction, which
works ok for limited output of parts. If I were producing
larger parts or more parts, I'd attach a heater/thermocouple/
controller to the mold and set it for about 200F.
-jiw