I've read a few things on the web that drew my attention to a lesser known feature of the A4988 drivers. Delta printers tend to show artifacts or ripples on prints. The A4988 drivers have a mode that can be used by grounding Rosc (IC pin 13).
I decided to lift a heatsink on the unused Z2 stepper driver, and find out if it's easy to ground Rosc. It turns out, it's not super easy but if you can solder (or even just remove) SMD resistors, then bridge the gap with solder, that's what it takes.
I highly recommend trying the suggestion from user rq3: Leave the resistors on the board, just add solder on top to bridge them.
I began by taking photos then removing the Trigroilla Pro motherboard to work on it. Then I located and traced the Rosc pin to "R49_"... X, Y, Z and E. This resistor seems to connect between Rosc and Gnd, so bridging it is what I did.
I didn't get it right on the first try. One motor worked. I had the Z motor endstop in the probe endstop socket. After that, one motor still wouldn't go. The logical reason for that is if the solder bridge didn't make proper contact. It turns out, if Rosc is left floating that motor driver won't rotate. It will simply hold the motor in place.
I haven't confirmed if this did actually set the Rosc mode properly, but the printer still works afterward so I'll leave it like this.
A video of soldering is here: https://www.youtube.com/watch?v=blBsU985R-c&feature=youtu.be
The resistors are below the heatsinks, which stay in place.
Overview of the stepper chip: Thu_Jan_09_15-43-10.jpg
Chip closeups: Thu_Jan_09_15-40-42.jpg and Thu_Jan_09_15-40-35.jpg
Tracing the PCB track and via: Thu_Jan_09_15-42-11 is the top side
PCB from underneath, tracing the vias: Thu_Jan_09_15-41-41
Those last two photos are meant to indicate pin 13 goes to a via, then on the other side of the PCB it heads down to another via before emerging at R49.
There's a Gnd via to the right of the Rosc one. Both are right above the resistor (Thu_Jan_09_15-40-26.jpg and Thu_Jan_09_15-39-56.jpg)
Does anyone have suggestion what I could buy to replace the hot end heat break / throat from a PTFE through to an all-metal? I swapped this $2 piece on my Ender 3 to make it an all-metal hot end, but I can't really find anything fitting for the Predator. I would not bother to replace the whole shebang.
yesterday i got my Predator. I have assembled it and level the bed with the automatic levelling module.
Now i have the prblem, that the distance to the bed is not the same on the whole Plate. It is Always on the left higher and on the right the nozzle scratches the plate.
No matter which model i want to print, and no matter how big it is. The Printer is always on the left edge of the model to high and on the right edge it scratches the Surface. (See the Picture). and the difference between left and Right becomes bigger and bigger
No my first thought is to localize if the Problem is an mechanical or a Software Problem what do you think guys?
Thank you for your help