The C-Bot has been a lot of fun to play with. And slightly dangerous: “Quick” five hour prints can easily cost close to $20. And while it’s been good at printing large vases and shelves, I’ve not been happy with it’s small-scale detail. The biggest problem is the 1.0mm E3D-V6 Volcano nozzle leaving blobs all over the place. But after a good… 12 hours of making test prints, I’ve finally got it to a place where I’m starting to get happy with the results. Below I’ll walk though the details.
All of the vases and shelving I’ve made (here, here, & here) have been printed at 45mm/sec, in PLA, at 250 degrees. Which is way to hot for PLA, but I learned that when slicing in Simplify3D’s ‘vase mode’, at that speed, if lower temps are used, the print will delaminate into a slinky when done.
For whatever reason, 45mm/sec was a very important speed in my head, so I spent days trying to calibrate the nozzle at that speed. But it’s been hard. So finally today I brought it back to 30mm/sec, and finally, with a ton of fiddling, got some good results. The slicer terms I discuss below are based on Simplify3D‘s settings.
Compare prints A & B (500 micron layers you see there), each 40mm across:
Same model, same orientation, different print settings.
For the life of me, I couldn’t get rid of all the zits on print A: Even though I had retraction enabled, whenever the hotend would come to the end of a segment, I could physically see a bit of filament extrude out. No amount of additional retraction, ‘wiping’, ‘coasting’, or ‘extra restart distance’ would solve the problem. Finally, in the ‘Advanced’ tab, I checked on ‘Perform retraction during wipe movement’, and print B was born. At this point I easily had a small bucket full of test prints, so I was pretty happy, and may have lol’d a bit.
From there, I gave the Make 2012 Torture Test a try again: I’d done it before, and… I didn’t take a pic, it looked like my printer had thrown up all over the place. So while the below image looks pretty sketchy compared to some finely-tuned .4mm nozzle machine printing at 100-200 micron, for this beast, I’m pretty happy:
(Note, I intentionally didn’t show the back : The rainbow arch did fail. But it almost made it… )
Based on all of that, here’s the highlights of the Simplify3D settings:
- Gizmo Dorks Gray PLA, printed on glass covered in wood-glue slurry.
- Nozzle Diameter: 1.0
- Extrusion Multiplier: 0.9
- Extrusion Width: Manual : 1.0
- Retraction : On
- Retraction Distance: 10mm
- Retraction Speed: 60mm/sec
- Wipe Nozzle: On (This pairs with the wipe setting in the Advanced tab, below. Weird they split the settings into multiple tabs…)
- Wipe Distance: 3mm
- Primary Layer Height: 0.5mm
- Top Solid Layers: 3
- Bottom Solid Layers: 2
- Outliner/Perimeter Shells: 1
- First Layer Height: 75%
- First Layer Width: 110%
- First Layer Speed: 75&
- Extruder: 210c
- Heated Bed: Off
- Fan turns on, on layer 3.
- Default Printing Speed: 30mm/sec (printing at faster speeds requires hotter print temps to get the filament melted in time)
- X/Y Axis Movement Speed: 60mm/sec
- Filament Diameter: 1.75mm (as measured, pretty spot on)
- Only Retract When Crossing Open Spaces: Off (this speeds things up, but lowers outer shell quality when only printing with one shell).
- Force Retraction Between Layers: Off
- Perform Retraction During Wipe Movement : On (this is where the magic happened)
So now that I have it working at that speed, next up will be to see if I can get similar positive results, but faster!