In article ,
"Bushy Pete" wrote:

KISS!

Assuming you are only doing these on a low production level basis,
(homebuilt!) and price is paramount, why don't you sit and watch a
thermometer and switch on and off the heater?



Hope this helps,
Peter


Peter, I had occasion to learn about temperature control a few years
back when we were developing test equipment for food laboratories. More
sophisticated temperature control algorithms (e.g. PID) were developed
because On/Off controls, whether manual as you suggest, or automated in
some way, simply do not hold temperature. (That's why people who cook
use gas stoves. Turn an electric burner off and it will continue to
transmit massive amounts of heat energy to the food for another fifteen
or twenty minutes.) Unless your process is unaffected by temperature
overshoot and fluctuations of 20 degrees F or more, flipping the power
to an electric heater isn't adequate. The OP is building a bicycle, not
an airplane, but I'm sure he doesn't want his carbon fiber frame
disintegrating at 60 mph.

Smitty Two