With a heated bed, the prints are not curling.

3D Printing
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1

With a heated bed, the prints are not curling. The new hex tunnels with no extreme overhangs are also an improvement.

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Nice improvement on the new hex-tunnel print!

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Thanks. Outside of the few extreme overhangs that will get hidden when the bearings are inserted, the print looked just about perfect to me. The next challenge is to keep this quality but do a faster print speed. The mechanics are not the problem; the Kossel does 300 mm/s with no problem. It’s the extruder, which is direct-drive now, and has Bowden friction to contend with. I’d like to switch back to a geared extruder at some point, but without quite as much gearing to keep the fast retracts (maybe 2x instead of 4x). Also should switch to a larger fan, say 200mm instead of 80mm, to actually cover the whole build area.

4

what are your print settings? (infill, perimeters, etc)

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3x perims, 0.35 nozzle, 0.4 extr width, 0.25 layers, 0.15 infill, 3 bottom / 4 top layers

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0.15 infill? it’s enough sturdy for printer parts? I thought about 0.5-0.6…

7

@Nicholas_Seward

I’m as surprised as you are. The box design adds a ton of rigidity, as does having well-bonded layers, as does the infill’s edge effectively adding another perimeter. I don’t think the stresses on this particular part will be too bad, anyway.

Nicholas suggests higher values for the bottom hub piece, ~0.5, which I think is being a bit conservative, but not necessarily a bad thing.