Basic problem - can not get "Extrude 100" command to work properly.
Bought a pre-built slightly used R2 from a friend who prints as his business. He set up scripts to level check, start up, etc. and tweaked the firmware to print large parts fast.
I'm totally new to this, but his build and setup allowed me to immediately make really good ABS prints of small detail parts that are my focus.
As I learned more, I started calibrating and testing optimized settings and found this calibration problem:
Using ABS 1.75 filament, an E3D extruder, and "purple" Polulu driver on E, I get the following results:
A. With Gcode set at E840 (firmware and eeprom):
Print extrusion rate way too slow. Minimal first layer adhesion.
"Extrude 100" command from LCD panel delivers exactly 50mm
G1E100F120 command from laptop/S3D delivers exactly 100mm
B. E set to E1680 :
Prints perfectly - 25mm calibration box dims all well within 1% and looks great.
"Extrude 100" from panel now delivers exactly 80mm.
G1E100F120 from laptop delivers exactly 200mm.
I can not find any line in script Gcode or Marlin that relates to "Extrude 100".
Where in Marlin, or wherever, do I look to figure this out? Maybe I'm missing something really simple. (I'm also new to Marlin, Gcode and S3D)
Note that the FT5 is printing great at E1680, but the calibration disparity bugs me.
Any thoughts appreciated.