With all the fighting I’ve done with SFACT and Slic3r over the last few weeks, I decided that I needed to cut to the chase and try using the de-facto standard, Skeinforge. It’s got a reputation for being absolute hell to get configured correctly. It does have about eight point seven jillion settings, but I went through them and after 3 or 4 false starts (layer height too high, then I needed to add start gcode to reset the extruder at the start) it’s producing quite fine output. My first print suffered from a combo of design problems and me not using the Cool module, but I’m on my 2nd print and that should be fixed.
I got fed up and tore down the X axis and finally replaced the crappy Chinese linear bearings on the X carriage with printed PLA LM8UU look-alikes from Thingiverse. I also replaced them on the idler side Z axis that I disassembled to get to the X carriage while I had it off, and I weakened the Z axis anti-backlash spring on that side as well, it was way more stiff than it needed to be and was causing excess drag.
I did some rewiring to run the wires for the right hand Z motor to follow one of the top gantry bars under the HDPE tubing there, it looks a lot cleaner that way. I’m moving the Z axis junction point to the left hand side frame where all the other wires are. This leaves the rest of the frame very clean looking. I still have some cleaning up to do of the Z axis wiring. I really should print an electronics housing soon too.
Also the Y axis setscrew is digging into the Y motor support, and the Y axis seems to be a bit uneven in the prints (could be related).
I reduced the “jerk” settings in the Marlin firmware because drawing some of the circles at high speed was causing a vibration in the frame that transferred to the printed object.
I redesigned the power jack holder that I had trouble printing and re-skeined it with the cool module enabled. It’s printing slow because it was set to 60 seconds minimum time per layer, but I’m going to leave it all night anyway so it doesn’t matter. It also has more support than the original design so it’s all good.