Using solely extruder block stepper motor & it runs HOT!

#1

Hi guys,
If you are using only the stepper motors on extruder block, I would suggest you to switch back using both motors and adapt to what MartinKing’s solution.
http://zeeproforums.technobly.com/uploads/default/original/1X/d9176b3c3d92244a3de5a90e7c7a1821aa04a641.PNG

You see, the stepper motor driver on the bottom of the board
which looks like this

Have a knob that can be varied to provide different current and this can be tuned using a voltmeter with output is in mV.

Tuning them is quite a pain, that’s why I believe using MartinKing’s attachment is prob a cleaner solution.
If you are careful and have lots of patience you can follow this guide to tune them.

For the Z axis you need about 0.3-0.35mV (through testing)
X Y axis you need about 0.25 mV (someone from ZeePro told me)
and the Extruders were tuned at 0.4mV, because it is driving two steppers
But if you are only using one of them, you want to also tune it down to 0.25mV.

#2

Good info,thanks Winston! RepRap Stepper motor info

I_TripMax= Vref/(8*Rs)

One question though, why not just plugin both motors? The bottom feed still doesn’t come into play as far as I can see. The stepper driver is just tuned to see two sets of coils. Personally I think I’ll be tuning mine for one :smile:

#3

Ya, having both plugged in and use MartinKing’s attachment to ensure the filament feeding is prob the way to go. haha I stripped everything out that wasn’t needed when I was debugging these salvaged units I got from cragslist, that’s why I didn’t have them plugged in.

#4

I only use my top motor but leave the bottom ones plugged in just to keep thing balanced. I might retune mine when I get around to using Octopi but its working good for now and I don’t want to break it :smile:

Thanks for the information