On 1/26/2018 4:58 PM, Mike Coon wrote:
> Not a very helpful contribution, sadly, but that chart relates to wire
> in free air (presumably). As soon as you put it in contact with the foam
> it will cool down and not cut. You really need something that is
> thermostatically maintained ...
Exactly. You can use the wire itself as the sensor - its resistance
varies with its temperature. So you just need a little circuit to
maintain a constant wire resistance. Adjustable, of course to get the
temperature that you need. I'm not enough of a circuit designer to tell
you how to do it, but I'm sure that someone over at S.E.D. would enjoy
the challenge.
Bob