Instructables

Id like to build a small test tube heater with nichrome wire. Where do I start?

I would like it to be variable from ~100C-400C and have minor experience in electronics.

iceng1 year ago
Take an old toaster apart for the nichrome wire and wind it around a ceramic tube that can accept your Pyrex test tube.

Power the tape from a variac or phase lighting controller through a step-down transformer 120:40 and start heating.

To maintain a temperature get an omega PID control.

And it wouldn't hurt to wrap glass fiber insulation around the heater.

A
iceng iceng1 year ago
BTW solder wont work, use ceramic wire twists or split bolts
to connect copper to nichrome..
frollard iceng1 year ago
+1

And as always with electricity; even a third of line voltage can be dangerous if not respected; if in doubt, don't touch a running circuit because the energized nichrome will happily conduct current as well as heat into a human body :D Always unplug before adjusting.