Wilson 2 Kit Issues


#1

So I have put together the Wilson 2 kit and have the bed levelled, motor currents set, and I upgraded to Marlin 1.1.8 and patched a few files to support the PICA and the rack and pinion setup, and my first layer looks pretty good.

I seem to be having two specific issues right now:

  • when heating the bed up beyond 72 C causes a heater fault and freeze
  • when I was printing a single cube (20x20) near the end of the print it had a thermal runaway, yet the temperatures shown in s3d were less than 3 degrees from what the hot end should be and the bed seemed to be fine.
  • there appear to be some lines on the print where every 4 or 5 layers you can notice it, especially on corners

I am a little suspicious of the arduino that came with this thing, I was thinking about trying to switch it out for an “official” one I have lying around.

I definitely have upgrade plans for this machine, but I wanted the stock kit to be working well first.

The slicer is simplify3d, and it is running through the usb cable.

EDIT: The ribbing seems to be about 0.5mm in pitch, which is exactly 1/4 of the leadscrew’s 2mm (effective is 8mm because of 4 start).

My configuration if anyone interested: https://gist.github.com/madebyjeffrey/87bf7d4801897b81f29a28b02921a402


#2

Have you run a PID tune on the bed and hotend?

Going above 72c on the bed can be pretty taxing. If it’s in bang bang mode it may be tripping on the way up. Is the bed insulated on the bottom?

The ribbing could also be due to the thermal expansion of the bed from bang bang mode as well, or from power droop from the bed turning off and on.

Switching to PID control may resolve your issue.

Do you notice any wobble in your rods when moving up and down the Z axis? Could try reseating the couplers.

Are the thermistors properly attached for the bed and hotend?

Do you have a part cooling fan blowing on the hotend? A silicone sock for the hotend can help maintain more stable temperatures and prevent wild swings.


#3

PID has been run on the hotend, the bed ran but failed - will have to investigate tomorrow. Best I can do regarding insulation is cork on the bottom - however it is not currently possible to adhere it.

I have changed out the couplers for the common spring type as it has less rigidity. The ones in the kit do not have any good amount of flex. Now the z axis when rotating only moves a little bit (like a small vibration). Prior to this, the kit included some large bearings meant to hold the leadscrew in place - I am not sure this is a good idea because it would force the leadscrew to move from its “natural” position.

Thermistor is SMT on the bed, the hot end seems to be quite fine.

There is a part cooling fan included and a silicone sock. Both were used in PID tuning of the hot end.

EDIT: Forgot to mention during autotune it did go above 73 without timeout. It was also about 13C in the air vs about 20C last time (at night in basement without furnace on).


#4

That narrows it down a bit. I’d say you have either a bad thermistor or maybe the wrong thermistor selected in the firmware.


#5

Thank you for posting your configuration file. I am finally getting closer to finishing my “Oldest unfinished Wilson TS kit” to be more similar to a Wilson II. I was I was concerned about getting the changes to use a PICA board and threaded rods done correctly. I am pretty excited that you posted this for us as it will prove to be a great help. My PICA is a now older REV C 24V model. I am not sure what the changes were made are in newer PICA boards so I am starting with this somewhat older model for now. I do not know, for example, if Marlin 1.1.9 may not like something it sees in my setup.

Again, I sincerely appreciate you posting your configuration file!