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Diamond Hotend, Duet Wifi, Mini Kossel, RepRap firmware

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I do not own an Ultimaker printer but have adopted Cura as my preferred slicer because it is so awesome.

Sorry if that is bad and happy to donate for using it.

Anyway, it has been a long driving goal of mine to print a 3D Benchy boat in color. Until now, the only Slicer I know of that is able to work with mixing extruders and virtual tools is Slic3r.

Unfortunately, Slic3r cannot assemble the 3D Bency model correctly and I have not been able to achieve my goal.

Enter Cura 2.6.0 beta. At last! 3D Bency parts are able to be opened, selected and merged correctly!

Yea! Will I finally be able to print a color Benchy? Will my life finally be complete?

I configure up to 8 extruders in Cura, even assigned the appropriate color from the color pallet, on each extruder under start code I add the command to change to the virtual tool - t0, t1, t2, t3, etc.

I select each part, assign an extruder (tool) to that part, fuss with prime tower settings to remove errors on prime tower. Cool!

I export the Gcode..... Upload it to the Duet, hit print and wait.

The result was not pretty. All three extruder motors spun crazy, jamming filament in the nozzle, excessive grinding, then retracting a huge amount, pushing it back in, more extruder spinning, molten filament everywhere, look out! lol cancel, abort, stop, unplug ! haha

So, I back up a bit and try slicing a single color object with Cura and the result is exactly the same.

I back up once more to Cura 15.04.06 or whatever it was, and got the same result again.

My start G codes must be messed up, but they are the same as in Slic3r.

I will go back and retest a single object from Slic3r to ensure my start Gcodes are good.

My comments/question is does Cura look to support mixing extruders using virtual tools? The virtual tools are configured in firmware and contain mixing ratios of the three inputs. For example, T4 could be a mix of the three colors producing a specific color. T5 a different mix, etc. We can also change mixing ratios on the fly of the existing tool. Just different ways of handling it.

Thank you for reading.

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ou need to do several things: comment out M83 in config. Insert M82 in your start.gcode.

  • You need to use Volumetric printing. Both in RepRapFirmware and use Marlin (volumetric) Gcode Flavor.
  • Insert M200 P1.71 in config.g and startupg.code
  • Setup all your filaments to be 1.1284mm (instead of 1,75mm) now you run volumetric.
  • Enable firmware retract in config.g M207 S1.5 F3000 - this only works if you use Volumetric Gcode in Cura, or Cura doesn't send the right gcodes.


*Where I learned about dimensions to enter: http://forum.seemecnc.com/viewtopic.php?t=7924

*A blog-post I wrote about all of this (working on a new one) - https://betrue3d.dk/using-duet-with-cura-and-diamond-hotend-and-firmware-retract/

Problems so far (mains):

  • Seems Cura only really manages to print 2 colors.. it _does_ use more colors, but if you use more than 2 colors on 1 layer, it only goes to the Prime tower for 2 of the colors... meaning its causing a lot of.. muddle things in the print..
  • You need to set all 5 temperature settings pr filament the same (ie: 200c) or the printing process stops a lot.. say, if first layer was set to 205 instead of 200, it does wait for it to reach 205 whenever it changes to a new color.. even if it is in layer 20.
  • Waiting for temperature changes etc takes place at last position of the printed part, and not some logicial place like the wipe tower.
  • Some very, very slow moves takes place the first few layers from the printed parts to the wipe tower... I have not been able to figure out, where this very slow move speed comes from.. also not entirely sure why it makes these moves - it's not just slow movespeed for first layer

Edited by Guest
It didn't like my lists with urls.

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