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APR 18 2023


Temp Controllers

Cabinet Fan

Z and X Fans (Y has one too)

Video trying, and failing,
to show you noise differences

There are two things I enjoy. Comfortable temperatures and silence.

So it shouldn't be a surprise that stepper motors roasting under normal use and cabinet fans trying to launch themselves into outerspace are not my cup of tea.

The manufacturer will tell you that the normal operating temperature of steppers is around 120F. Basically, almost too hot to touch is acceptable.

While the may or may not be true, I can't help but feel keeping things cool can only increase their usable life.

On top of that, I enjoy working in complete silence. Some people like white noise. Others like listening to music. I can't do it. I've tried. It drives me crazy.

If I can work in silence, and maybe increase how long my machine lasts, I'm doing it.

I put adjustable-speed 120mm fans on each motor with a temp sensor on the Z. I figure the hottest motor will be the Z, so may as well control the setup off of that one.

Then I removed the OEM cabinet fan. It's way too noisy, especially for the amount of air it moved. And it runs even when the machine is e-stopped.

So I shoved a 9" desk fan in the cabinet the best I could and put a temp sensor on that, taped between the drivers.

When the machine is e-stopped, neither the drivers nor the motors are generating any heat, the fans don't run and I can work in silence.

When the machine is at idle, I have it set so the motor fans kick on at 95F with a 4 degree overshoot.

The cabinet fan is set at 90F. They click on and off at reasonable times and, even when running, are very quiet.

I have the RPM controllers set at a speed that allows them to run for a few minutes, then click off.

Versus, say, full speed where they'll cool the sensors down too quickly and it's on-off-on-off-on-off nonstop.

Project Parts List

Stepper fans x3:

Cabinet fan:

Stepper fans controller:

Cabinet fan controller: