How to pull/push filament with gcode?

I Hello, can you help me?

I have bowden extruder and try to write push and pull filament gcode (two different small files).
I need about 60cm pushing/pulling

I try this:
M117 push plast
G21
M82
G92 E0
G1 E600.0 F1000.0

M117 pull plast
G21
M82
G92 E0
G1 E-600.0 F2000.0

and theese:
and it doesn't works

M117 push plast
G91 ;relative positioning
G1 E600 F1000
G90

M117 pull plast
G91 ;relative positioning
G1 E-600 F2000 ;retract the filament
G90

It doesn't works on cold and hot hotend

would the G10 and G11 commands do what you need

- G10 S<1 = long retract, 0 = short retract = default> retracts filament according to stored setting
- G11 S<1 = long retract, 0 = short retract = default> = Undo retraction according to stored setting

in firmware docs.

What length it will retract?

And why my codes do nothing?

Your type of machine, particularly the firmware it is running in this case, is critical to answering questions correctly.

For most machines I'm familiar with, G90/G91 only change the absolute/relative mode for the positioning of the nozzle. Absolute/relative of the extruder drive is handled by M82 and M83.

Many firmwares have a (defeatable) protection in place that prevents the extruder drive from running if the hot end is not up to temperature. If you're running Marlin, Repetier, or RepRapFirmware, the command to allow cold extrusion should be some variation on M302. [reprap.org]

Edited 1 time(s). Last edit at 10/01/2016 02:48PM by IMBoring25.

My last sentense was about that: no hot no cold hot end doesn't works.

My firmware is RepetierFirmware (Prusa i3 with Melzi).

Can you show me example of working code where push or pull long distantion?

I need about 60cm

this works fine

Quote

M117 pull plast
M109 S180
G21
G90
M83
G1 E-150.0 F2000.0
G1 E-150.0 F2000.0
G1 E-150.0 F2000.0
G1 E-150.0 F2000.0

this doesn't works

Quote

M117 pull plast
M109 S180
G21
G90
M83
G1 E-600.0 F2000.0

any ideas?

Firmware bug?

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42
Firmware bug?

I think there is some option to ajust max move of filament (Repetier firmware)

Yep, you answered your own question. The parameter is EXTRUDE_MAXLENGTH and it's defined as follows:

Quote

When you try to extruder more then this in one move, the extrusion gets ignored. Protects for wrong defined extrusion commands, e.g. if you stopped printing and did not reset extrusion position to 0.

Either modify this in your configuration.h and re-flash the firmware or just make your longer extruder moves in multiple steps.