Continuous Printing via Pneumatic Part Ejection

Simple setup to allow shorter, small parts with larger surface areas to be removed reliably from a Prusa Mini. Also showcases the ring displays that I designed. Can be seen as somewhat of a follow up to my last video.
One kilogram of this filament is being used to print as many ring displays as possible.

[@3DPI67]

Nice build! I like how the printer controllers the actuators

[@capitankak]

Fantastic idea, great ingenuity. Thanks for sharing!

[@scruffy3121]

nice project!

[@samvzughusjcdvkauic]

Super cool build! I've seen printers where the extruder head rams into the part to clear it from the plate, may I ask why you used your setup opposed to that?

[@kennetek]

Great question, I actually have, the previous video I posted was showing the print head ramming a part off. I wanted to move away from that since it only works on certain types of parts, usually if they are tall and have a small surface area contacting the bed. The finger part can be ejected in this way, and I used to do that. However, the base is really short and has a large surface area relative to its height, which means the belts just skip instead of actually disengaging the part. That's why I built this, otherwise the simpler solution would definitely be to just use the printer.

[@rocky6344]

chat this is fire

[@AustensFabShop]

How does it automatically start the next part?

[@kennetek]

I have the slicer put the blob as custom start g-code and the ejection as custom end g-code, so each object does the full cycle, and then appended the two parts together in Notepad++, and then copy-pasted that merged block of g-code a hundred times. I think Marlin has a looping command with M808 but I am unsure if that works.
The print progress is updated via M73 commands inserted by Prusa slicer, so it always ends at 100% for each part and then resets, even though it has barely made a dent in the full g-code file.

[@AustensFabShop]

@@kennetek Ahh, okay, so you have one MASSIVE gcode file that just copies and pastes. I'm working to integrate my Desno robotic arm to remove and replace mag build plates in my X1Carbon. I'm familiar with start and end alterations with limit switches for camera time-lapses. I was just curious how you were able to get it to restart. Great concept!

[@rickywong5551]

What filament is this please?

[@kennetek]

Amolen Ebony Black wood PLA from Amazon, which is a nice matte dark gray color. A bit lighter than Polyterra charcoal black, which was one I tried to use as a substitute (much easier to print), since both are matte.

[@rickywong5551]

@@kennetek thanks appreciate it