ErikZalm/Marlin — Issue #102: Strange behavior after G92 X?? Y?? command
Author: mikeq3
Created: 2012-03-06 19:57:37+00:00
State: open

After a G92 command with X Y Z E specified, Z feedrate is very slow and E commands behave incorrectly. E comands acts as if they are relative instead of absolute. Here is the start.gcode I have been using for the last 6 months. This code no longer works correctly when I installed RC2. It worked with no problems with a pull I've been using from 01/30/12. I isolated it to the G92 with any X or/and Y option. Doesn't seem to be a problem if Z or/and E is used.

G21 (MQ start.gcode)
G21 (Metric: The unit is a millimeter)
G90 (Absolute Positioning)
M109 S230 (Set extruder temp to 230 degrees and wait for heat up)
G28
G1 Z50 F2000
G92 X-95 Y-104 Z220 E0 <-- AFTER THIS EVERYTHING IS NOT FUNCTIONING CORRECTLY
G1 X0 Y0 F2000 (go back to the center)
G1 Z210 F100 (let the platform go up slightly, start slowly) <- THIS COMMAND GOES VVVERY SLOW
G1 Z0 F400 (we don't have all day...) <- AND THIS AS WELL
G92 X0 Y0 Z0 E0 (make the center the origin)
G91 (Relative positioning)
G1 Z35 F400 (lower platform for cleaning nozzle)
G90 (absolute positioning)
G92 E0 (zero the extruded length)
G1 F75 E7 (extrude 7mm of feed stock)
G1 F75 E5.5 (reverse feed stock by 1.5mm) <- COMMAND WILL NOT REVERSE FEED STOCK AFTER G92 ABOVE
G92 E0 (zero the extruded length again)
G91
G1 Z-1 F100 (rise platform again) <- IF THESE RUN AT ALL THEY ARE THE PROPER SPEED
G1 Z-34 F400 (rise platform again) <--
G90
G1 Z0.4
G21 (end of start .gcode file)