Setting up 3D printer that does not use filament

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So you have a 3D printer, and you want to configure your slicer so it can create g-code for it. The most obvious data is the size of your print envelope, but a less visited problem is how to deal with pellet printers or past-based extruders.

Your printer for sure can respond to your commands, so after a while, you have a good understanding of how the amount of material needed to get your desired line width at a given layer height. That ratio would be the number of steps/mm the extruder needs to print the sort of lines that you need. Now you just need to tell your favorite slicer that. If you are like me, and your favorite slicer is PrusaSlicer, please be warned that a 1200 mm cube is its maximum print envelope (that was a no-go for one of my concrete printers). 

On the other hand, Cura was happy with a larger volume (but I have not asked or tested their max volume). However, I was expecting the "filament diameter" in the extruder configuration in Cura to be the number I could play with to set the proper extrusion ratio. I was surprised that changing that number did not affect the extrude values of the print moves (I am not a regular Cura user). I saw I could change the flow percentage, which will affect the extrude values, but it will also mess with the preview (as the flow decreases, lines become thinner, which is not desirable). 

So, I settled with the extruder's steps/mm settings on the printer firmware and would accept Cura's calculated extrude numbers. I will set my printer's extruder scale so it works. Wish me luck!


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