MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

RE: MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

shabaz — Mon, 01 Dec 2025 05:52:49 GMT

I've been working on the PCB for the control board, which will form the next blog. I could not come up with a neat way to handle the LCD, so the plan is, to have a front panel which contains nothing except a rectangular hole for the display and a circular hole for the potentiometer shaft, and nothing else.

Then, the following smaller PCB will be glued behind the front panel.

The through-hole pins protrude a bit, but they could be flush cut, or unsoldered after programming (not all will be used), or double-sided sticky foam could be used to leave a gap between the front panel and this PCB. I did consider SMD connectors instead of through-hole ones, but through-hole ones are something I don't need to purchase.

RE: MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

shabaz — Tue, 18 Nov 2025 17:10:49 GMT

The board arrived today, although I have no parts yet to build it.

The four corner holes serve no purpose when used with the Multicomp or Hammond enclosures, they are there if a DIY enclosure is made that needs the panel screwed on.

RE: MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

shabaz — Mon, 17 Nov 2025 05:22:31 GMT

Here's the draft schematic for the Control Board. I've not done the PCB design yet, so if anyone spots any errors or has suggestions, please let me know, it would be appreciated!

EDIT: I'll bring out the I2C connections, so that the SPI TFT screen can optionally be replaced by an I2C LCD.

RE: MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

michaelkellett — Mon, 10 Nov 2025 09:33:15 GMT

If you ever revisit this you might like to consider using something like this for the power switch.

They cost a bit more but you get the high side switch with low side control with current limiting, current sense and other protections all in the one package. They won't switch fast but you won't need that for heater control.

I like your schematic with connector pictures.

RE: MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

genebren — Fri, 07 Nov 2025 16:28:25 GMT

Nice project. There are a lot of uses for a settable temperature. I have used something similar as a tiny environmental chamber testing thermistors and temperature stabilizing thermally sensitive components (one such device was a light source that needed to be held at a certain temperature to produce the desired wavelength of light).

I might need to revisit this.

RE: MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

DAB — Thu, 06 Nov 2025 20:32:10 GMT

Nice post Shabaz.

I remember when we used heated crystals for frequency standards.

RE: MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

shabaz — Wed, 05 Nov 2025 23:32:12 GMT

Tidied up the text and improved a couple of the component footprints, and the updated files are on GitHub. I got the project name wrong on the board, but it's too late, it's submitted to the PCB manufacturer now.

This is going to be a white PCB since the case is beige.

RE: MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

shabaz — Wed, 05 Nov 2025 20:22:19 GMT

One other possible use-case; tempering chocolate! That needs pretty accurate temperature control so one may want to do some calibration beforehand. Also, the code would need tweaking to really focus on removing even fractional overshoot.

I've only tried to temper chocolate a couple of times, using a basic thermometer, and I've found it hard (but luckily had success). Also learned that the times you want to temper chocolate (summer time) isn't a super ideal climate for subsequently cooling the chocolate (since most homes here are not air conditioned), so you kind of have to take a leap of faith and use the 'fridge briefly even though that could so easily ruin things.

RE: MiniThermaDrive: Fun with 3D Printer Heating Elements - Part 1

obones — Wed, 05 Nov 2025 16:15:17 GMT

Hey, that looks nice
Do you think it could be used to heat a metal "pot" inside which I would place my PLA left overs from previous prints?
The idea would be to have it hot enough to be able to pour it into silicone molds, but maybe 150°C would not be enough