Enraged wrote:regarding your math, in the first section I think you forgot to square the (0.875/0.2)**2, it should be 19.14, which throws off your math, correct?
Correct, thanks for catching that!
Enraged wrote:I was having some difficulty understanding you math, but from the looks of it, that final Ve is actually the speed of the extruded filament exiting the orifice, and not the speed of the filament entering the extruder. Is that right?
That's right. Maybe I should have given a more detailed explanation. I had in mind the interruptions observed in the extruded plastic at high speeds by Bart and Jeremy and tried to see why this might have happened. It seems that they might have hit the stepper limit, which is 375.8 mm/s if the stepper is in microstepping = 16 and the rest of the stepper and orifice characteristics are the same.
The speed of the filament entering the extruder is the
pinch wheel feed speed, Vg.
Also, the
extrusion length per step, Lse, is calculated to see if the alterations in extruded plastic thickness, which are some times observed in other setups, can be attributed to the stepper action being discrete (in steps) and not continuous. By knowing these values one could possibly have some numeric guidance in troubleshooting print problems.