Hi there, just a word of warning: Last week I had to exchange the Z-axis driver on my 2yo Fab Mini V2. First, it started missing steps, which I attributed to my increased z speed setting (2 mm/s) but reducing this did not help for long. Then, the z-axis quit moving in the middle of a 1h+ PLA print job.
I found the z-driver UNL2003A has failed, and after replacing it, the z-axis moved ok agin. While testing, I noticed the new chip running quite hot and glued a small heat sink on it. I also checked the motor windings, all 4 are at about 30 ohms, so not the problem. Now, while printing, I measure up to 60 C on the heatsink, no matter if the case fan is running or not!
I believe, the problem began when I started printing ABS with a shroud around the printer to keep it warm. Not a good Idea!
Hi, for the M200 stepp driver modifications are possible. Due to the similar motherboard layout I am wondering whether anybody in this group already did that and can report improvements in terms over better and more silent prints.
I have modded my stock heatbed to heat a little bit faster.
The result was a 80W heatbed, thus requiring a 120W power supply. The stock one will power off if used with this mod.
The mod itself is pretty simple if you are handy with a soldering iron.
I have split the heatbed resistor coil in two and soldered the halfs in parallel, thus obtaining two times the power and two times faster heating time. See picture for details.
ABS prints very good now.
on my printer I have the problem that on longer prints (>4h) the extruder fails to forward the filament and stops printing. Especially when retraction is turned on.
I figured out that this might be because of the stepper motor of the extruder which gets extremely hot. My theory is that the forwarding gear for the filament also gets too hot and then melts it a little bit which causes the feeding fail.
I placed a cooling fan right above the stepper motor where the filament gets into the tube. That solved this problem for me. Right now I am looking for a more elegant solution, I ordered some smaller fans and heat sinks.
Perhaps someone has the same problem, this might be also a solution for you.
I've looked all over to try and find a video or guide to tighten the belts on this thing.
My circles have a clear deformation with 2 flat sections for the circle but I cannot for the life of me figure out how to tighten it without completely disassembling it.
any help would be great.