Page 1 of 1

Purge Lines

Posted: Mon Mar 04, 2019 5:47 pm
by jvingaard
Hello,
Maybe someone can help me?
I am trying to print a purge line before every print, but are only able to print in air.

this is my start g-code.

G21 ;Set Units to Millimeters
G90 ;Set to Absolute Positioning
M82 ;Set extruder to absolute mode
M107 ;Fan Off
M851 Z-2.23 ;Set Z-Offset
G28 ;Move to Origin (Home)
G29 ;Auto Bed Leveling
G1 X0 F8000 Y0 F8000 ;Move to home

;G92 E0 ;Reset extruder position
;G1 Y10 X10 F500.0 ;Move to position
;G1 X60 E9 F500.0 ;Start purge line
;G1 X100 E12.5 F500.0 ;Finish purge line

G92 E0 ;Reset extruder position
G1 F{travel_xy_speed} ;Reset travel speed
M117 Printing…

What i really would like to do.

1. initialize the print
2. Print purge line
3. Drob bed before move
4. print

Re: Purge Lines

Posted: Tue Mar 05, 2019 12:31 am
by Vicky@Raise3D
There has one Z homing code missing after move to home.
And there have four codes being commented which are related to your purge issue.

Re: Purge Lines

Posted: Tue Mar 05, 2019 12:34 pm
by ocelot27
I like to do a little blob and then have the nozzle just move away from it and lower - its faster and cleaner and wastes less filament - something like this -

After homing:

G1 X5 Y5 Z2.5 F1000; set height and location for blob
G1 E2 F500; extrude small blob (2-3mm is usually good)
G1 X10 Y10 Z0.3 F2000; drop and move away from blob leaving nozzle clean

You can fine tune the size of the blob and height at which it is extruded to get things perfect - you don't want to do it too close or the nozzle will pick up plastic on it's sides.... and, of course, this assumes you're not printing in the location these commands.


-john

Re: Purge Lines

Posted: Tue Mar 05, 2019 7:14 pm
by jvingaard
ocelot27 wrote:I like to do a little blob and then have the nozzle just move away from it and lower - its faster and cleaner and wastes less filament - something like this -

After homing:

G1 X5 Y5 Z2.5 F1000; set height and location for blob
G1 E2 F500; extrude small blob (2-3mm is usually good)
G1 X10 Y10 Z0.3 F2000; drop and move away from blob leaving nozzle clean

You can fine tune the size of the blob and height at which it is extruded to get things perfect - you don't want to do it too close or the nozzle will pick up plastic on it's sides.... and, of course, this assumes you're not printing in the location these commands.


-john


Thanks John.
that led me in the right direction,
I ended up doing this.

G1 Y5 X5 Z0.2 F500.0 ;Move to position
G1 X60 E9 F500.0 ;Start purge line
G1 X100 E12.5 F500.0 ;Finish purge line

I really like the purge line it lays down. :-)