So much of my design lately centers around heaters.
My regular gig, I build 3D printers for a living. The printers I have spent over a year now working on utilize heaters.
I have been using 12volt DC heaters in the form of silicone pads from China. The downside to this arrangement is that I need a large power supply. 40 amps is a lot of juice and money adds up fast in wires, connectors, etc.
So today I started working on making my own heater.
I purchased a length of NiChrome wire from the local heating supply company, and set to work.
First attempt turned out really bad.
I tried to cheese it by using regular household silicone caulk. It didn't set right and turned cuumbly.
Today's attempt was different.
I used a sheet of Mica, taped the NiChrome wire to the sheet with kapton tape, then added silicone RTV, making a sandwich of silicone RTV, mica and heater wire, with a thermistor handling the temp reading.
I had success...
Well kind of....
The thing works. Draws 254 watts at 220v AC.
Heated up to 120c no problem.
Except that the silicone is not curing properly. I think I got an old tube. It remains sticky.
So tomorrow I'll grab a tube of new silicone rtv and hope the catalyst in it will get the other stuff to cure as well with another layer on it.
It is just a prototype and although it is the shop machine, so I do use it to make stuff.