AndersE
Posts: 220
Joined: Sun Feb 02, 2014 4:40 pm

Retraction bug. (2.1.1) and extrusion bug.

Wed Jul 16, 2014 6:29 pm

I like to have a z lift when printing, but i have noticed that it will only raise z IF extruder retraction is also set to something.

So if retraction is 0 and z-lift is set to 0.20 the nothing will happen.
If retraction is 0.1 and z to 0.20 THEN it will lift.

Very annoying.

The next thing is: i have set up startscript so it will extrude 10mm filament at beginning.
But it randomly run extruder backwards 10mm instead.

G1 E10 F300 ; purge nozzle

SimGa
Posts: 5
Joined: Mon Jul 21, 2014 12:54 pm

Re: Retraction bug. (2.1.1) and extrusion bug.

Mon Jul 21, 2014 2:40 pm

The issue that your extruder randomly retracts instead of extrude is based on the absolute positioning system.
If you extruded some material before you start your new print(and G1 E10) the extruder would get back to the position 10mm( Position is reset every start of the printer)

So there is an easy solution to get rid of this problem:

Instead of:

Code: Select all

G1 E10 F300 ; purge nozzle
you have to use:

Code: Select all

G91; set to relative positioning
G1 E10 F300 ; purge nozzle
G90; set to absolute positioning

User avatar
KeyboardWarrior
Posts: 480
Joined: Thu Jun 19, 2014 5:02 pm

Re: Retraction bug. (2.1.1) and extrusion bug.

Mon Jul 21, 2014 3:28 pm

AndersE wrote:I like to have a z lift when printing, but i have noticed that it will only raise z IF extruder retraction is also set to something.

So if retraction is 0 and z-lift is set to 0.20 the nothing will happen.
If retraction is 0.1 and z to 0.20 THEN it will lift.

Very annoying.

The next thing is: i have set up startscript so it will extrude 10mm filament at beginning.
But it randomly run extruder backwards 10mm instead.

G1 E10 F300 ; purge nozzle
Change the retraction to .01 mm, that's infinitesimal small and will trigger the retracts. For your starting script, need more information. What printer are you using, what does the entire starting script look like?

AndersE
Posts: 220
Joined: Sun Feb 02, 2014 4:40 pm

Re: Retraction bug. (2.1.1) and extrusion bug.

Mon Jul 21, 2014 4:08 pm

This is all i have on startscript:

G28 ; home all axes
G29 ; auto bedlevelling
G1 E5 F300 ; purge nozzle

AndersE
Posts: 220
Joined: Sun Feb 02, 2014 4:40 pm

Re: Retraction bug. (2.1.1) and extrusion bug.

Tue Jul 22, 2014 4:46 am

Thanks, i will try that instead..


SimGa wrote:The issue that your extruder randomly retracts instead of extrude is based on the absolute positioning system.
If you extruded some material before you start your new print(and G1 E10) the extruder would get back to the position 10mm( Position is reset every start of the printer)

So there is an easy solution to get rid of this problem:

Instead of:

Code: Select all

G1 E10 F300 ; purge nozzle
you have to use:

Code: Select all

G91; set to relative positioning
G1 E10 F300 ; purge nozzle
G90; set to absolute positioning

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