u/higgs8

So I print a lot of TPU as well as ABS. Unfortunately, as I found out, you have to do a cold pull before printing with TPU otherwise the hotend will clog, learned the hard way.

Now the official cold pull procedure is quite complicated, and there's no way I'm going to do it every single time I print TPU:

• Disconnect the AMS cable
• Disconnect the AMS PTFE tube
• Remove the AMS
• Remove the glass top
• Remove the hotend cover and cable
• Remove the PTFE tube
• Heat up extruder
• Cut a piece of ABS, push it into the extruder
• Extrude
• Cool down the extruder to 100ºC
• Extrude in reverse
• Put back the cover, reattach the fan connector, with a 9/10 chance it won't work
• Insert the TPU and finally now you can print

I've come up with a method that achieves the same thing entirely in software:

• Load a filament from the AMS from Bambu Studio
• Extrude a bit (on printer)
• Cool down the hotend to 100ºC (printer)
• Extrude in reverse until it looks like the extruder isn't grabbing anything anymore
• Unload the filament from Bambu Studio (it will "cut" the filament but it will not longer be in the cutting path)
• Load TPU from external spool

Would there be a way to write G-Code that could do all this automatically?