Well it took 4 days to dry sufficiently to do a test on the coil. The plaster felt relatively dry finally and room temperature (not cool to the touch from evaporation).
I did a number of graduated tests of the heater starting at 30 watts, using the variable power supply. Temps were kept below 200 to start with in order to dry out any remaining moisture.
There was also some odor from a small amount of smoke as the tape, which held the original coil in place, and the small residue of release agent vaseline burned off. I did this outside on the porch for ventilation. All went well and the heater was a success when tested up to 90 watts, at 12 volts.
This was below the temperature where the stainless wire glows. I.believe that would be somewhere around 150 watts, as estimated earlier with wire tests. I'm really happy with the result, and I was able to run my No. 83 hot air engine on the heate in a test. (see that thread here:
https://www.madmodder.net/index.php/topic,13865 ).
