12" I3V Build

[Dustin B]

Solved my issue. Apparently mattercontrol won't do anything the same size or smaller than the nozzle diameter. Model was 0.4mm walls, changed the nozzle diameter to 0.39 and it slices fine. So I made my own quick model with 0.5mm walls which worked fine from the perspective of getting it to print.

However I'm at a bit of a loss again as the gcode says my extrusion width is 0.4mm but the resulting object is measuring 0.8-0.85mm. I'd just re-done the e-steps test and verified my values before this print so I can't see it being out that far.

Put a multiplier of 0.48 in and end result was a 0.45-0.5mm wall thickness.

So confused.

[Dustin B]

Same results with PETG, 0.8mm.

Also ran the e-steps calibration with PETG. First 100mm was under by 2.5mm. Adjusted on the LCD and ran again then I was over by 3.5mm. So I put it back to the original value before running the calibration print.

When I reran the e-steps on PLA it was spot on. Am I making a mistake expecting pretty good consistency on the 100mm extrusion, or does that indicate something might be slipping?

The other thing I found a bit odd was that no matter what layer height I set the extrusion width stayed at 0.4mm in the gcode. Is that a quirk of MatterSlicer? Does slic3r let you set the width and then it controls the extrusion rate to get it?

[Dustin B]

Found this which is quite interesting and answering a lot of my questions about layer height vs extrusion width with a given nozzle diameter.

https://groups.google.com/forum/#!to...as/2FG_gUxa_fE

Looks like MatterControl was asked to allow setting the extrusion width, but hasn't done so and leaves it matching the nozzle diameter. So you could cheat by lying about your nozzle diameter to get close to the same effect as being allowed to specify the extrusion width.

The bigger issue I still have though is why I'm getting single wall prints that are double my nozzle diameter. Wonder if I just didn't notice it actually did an inner and an outer wall.

[Dustin B]

Response from MatterHackers:

Walls less than or equal to nozzle diameter: Not printed
Walls between 1 and 2 times the nozzle diameter: Overextruded
Walls greater than 2 times the nozzle diameter: Correct width

MatterSlice's handling of thin walls is something we definitely want to improve.

I'm going to try making a model that has 1.2mm wide walls for my 0.4mm nozzle and see how this calibration technique works with that.

[Dustin B]

Learnt the hard way couple days ago that you need to pay attention to where you run the USB cable from the Rumba. Too close to a motor wire and you'll get some very unhappy and frustrating results until you get it routed away from the motor wires.