Stepper Motors to hot to touch

Hey, I have noticed that when I’m printing on my Taz 4 that the stepper motors are getting to hot to touch, probably over 100 degrees Fahrenheit. I just need to know if they are supposed to do that and how I can fix it if it is a problem. Let me no what you guys think,thanks.

The stepper motors can get warm during printing- it’s not something to worry about- unless prints start failing or shifting during printing. As long as each axis moves smoothly you’re ok.

I’m just wondering if it’s worse with a heated box? I’m pushing 40degrees in my enclosure, 10+ hour prints :stuck_out_tongue:

Anyone have any good suggestions or links on passive cooling these little Nema’s, maybe help just a bit with heat dissip. Heat sinks maybe…?

Yeah, with a stock Taz4, fully enclosed, will start to fail when the temps at the table-top and the electronics air-input get to about 45C. For me, it was the Z-axis stepper motor driver that overheated, went into thermal shutdown, and then continued to extrude 35mm worth of part height at exactly the same actual height. Part was an ugly mess at 64mm tall, but the LCD claimed it was at 100mm. This happened twice, both when the air to the electronics enclosure was well into the 40C’s.

I ended up going to some length to isolate the airflow circuit of the electronics box, and I’ve posted a pretty detailed writeup of the enclosure and the ventilation isolation shrouds at:

http://www.tctrandolph.com/dropbox/IsolationEnclosureForTaz4Printer_v0.38.pdf

The change also involved modifying a setting in the configuration_adv.h (advanced configuration) file. The setting is described in the PDF file, but it essentially turns off the Z-motors when they’re not going to be used. It has helped moderate the Z-axis driver shutdowns that I experienced.

So far so good for me.

Regards,

Thom

As a data point, I am running the “first print” test on a new TAZ 6 in an open room and the X and Y axis stepper motors on my printer and at the midpoint in the print, the temperature of the Y axis stepper was 120F and the X axis was 125F.

That just sounds too hot to be normal.

UPDATE: at the end of the print, the X and Y steppers were each at 129F

See the “heat” section here: http://www.reprap.org/wiki/Stepper_motor

Most of the motors specs give the current for two coils that will give an 80 °C rise, i.e. > they can run at 100 °C> ! When using them on plastic brackets you need to under-run them to keep the brackets from melting. With PLA’s glass transition temperature between 60-65 °C, you have to seriously under-run them! Fortunately temperature rise is proportional to power, which is in turn proportional to the square of current (P=I2R), but torque is directly proportional so you can keep temperature under control without losing too much torque. For example, running a stepper at 70% of the rated current would result 70% of the torque and 49% (0.72=0.49) of the power dissipation and thermal rise.

100C ~ 212F

129F is only about 54C

All of your motor mounts are also printed in ABS, which has a Tg of about 110c. These temps reported are all within normal operating range.