On Sat, 16 Aug 2008 13:50:59 -0400, Wes wrote:
James Waldby wrote:
What temperature does this run at?

The block has 2 ea. 175W heaters [...] I set the controller for 450F

I was wondering how a kalrez o-ring would help your situation?
[...] Material Kalrez® Perfluoroelastomer Durometer Hard
[...] Highest Temperature Range +501°F to +600°F
[...] I cut and pasted that from the mcmaster carr website. Pretty spendy
though
AS568A Dash Number 109
[...]4079 +32° to +600°F 9568K421 $36.83

I wasn't aware of hi-temp o-rings like that, so hadn't considered
using them. Even so, for the next version I don't plan to use o-rings
but instead will attach a short close-fitting end-piece to the plunger.
My main concern with current version isn't the sloppy fit (.001"), but
instead that the plunger cools the block as it enters. Like the mold,
the plunger heats by conduction, but since I don't cycle it very fast,
the effect isn't significant at the moment. Anyhow, with an endpiece
a little wider than the plunger this effect would be reduced and possibly
I could lower the temperature setpoint somewhat.

-jiw