Page 1 of 1

Gcode? How to delay the start of the print ?

Posted: Thu Feb 18, 2016 11:26 pm
by Konky
This is the original gcode used by s3d at the beginning:
M907 E1400 ; increase extruder current
G28 ; home all axes
G1 X20 Y10 F3000 ; bring extruder to front
G92 E0 ; zero the extruded length
G1 Z10 ; lower
G1 E19 F200 ; purge nozzle quickly
G1 E26 F60 ; purge nozzle slowly
G92 E0 ; zero the extruded length again
G1 E-5.5 F400 ; retract
G1 X190 Z0 F9000 ; pull away filament
G1 X210 F9000 ; wipe
G1 Y20 F9000 ; wipe
G1 E0 ; feed filament back


I'm new to gcode.
My problem is that the hotend is not ready when the print starts.
Cura (UM2) waits for good 5-6 seconds in the beginning and creates a long string of filament before it starts printing.
S3D nearly immediately starts after heatup, the filament is not out yet so the beginning is a dealbreaker.

How can I add a delay of additional 3 seconds where it just sits in left outter corner and extrudes filament ?

Re: Gcode? How to delay the start of the print ?

Posted: Fri Feb 19, 2016 6:56 am
by CompoundCarl
Personally, I would just use a few skirt outlines in your slicing settings. That's the most reliable way I have found to get the nozzle reliably primed.

Re: Gcode? How to delay the start of the print ?

Posted: Fri Feb 19, 2016 1:47 pm
by Konky
I can try that but it will create crap inside print area in worst case.
The best way I used was just letting it float for a while and when it start moving you "hold" the end of the floated filament.
That way the print starts perfect with only a very thin line of filament pointing in the direction you wanted.

Re: Gcode? How to delay the start of the print ?

Posted: Fri Feb 19, 2016 11:24 pm
by Konky
I tried that and had still quite a lot of print failures.
The problem is this:

The print head starts drawing the skirt, it's not properly extruding filament because of the short launch time.
The skirt does not stick and once the head moved in one circle the skirt is ripped off partly and is dragged into the middle of the print zone.

So for me the skirt does more damage than good.

I think this is mainly because of wrong gcode settings for ultimakers, it just needs to extrude filament a few more seconds and it would be perfect.

Re: Gcode? How to delay the start of the print ?

Posted: Sat Feb 20, 2016 12:05 am
by Konky
I've solved it like this (old call is commented out and replaced)
gcode is simple after all

;G1 E26 F60 ; purge nozzle slowly
G1 E40 F60 ; purge nozzle slowly (longer)

Re: Gcode? How to delay the start of the print ?

Posted: Mon Feb 22, 2016 4:51 am
by atunguyd
I think you are addressing the wrong problem here, to me the real problem is why your skirt is not adhearing to the bed even if it is under extruding.

My print starts the skirt with nothing and then over about 20mm I start to see a very faint skirt which slowly starts to become more solid.

What bed are you using? I recently switched to using 3deez on my bed and havent looked back.

Re: Gcode? How to delay the start of the print ?

Posted: Mon Feb 22, 2016 5:23 pm
by Konky
I'm using a heated glass bed with blue tape on it (sticks very well)
The problem I had was that the first part of the filament does not seem to stick at all.
After spitting out a few cm more the filament sticks very well.

I guess that the ABS that is left in the nozzle tip does not have good properties anymore.
It will work with a skirt but I had cases that the filament that did not stick was dragged into my print, destroying the first layer

I kinda solved it with longer extrusion at the beginning

Re: Gcode? How to delay the start of the print ?

Posted: Sun Jun 12, 2016 3:31 pm
by Thomas_783
I have the same Problem at every print.
The Nozzle seems to be clogged at every start.
So less or no Material is coming out of the Nozzle at the start.
If the start goes wrong the whole Print is affected or failing.

The Wait command is:
G4: Dwell
Example: G4 P2000 ; (P time in milliseconds – S time in seconds.)



I changed the Code to wait 3 Times and purge the nozzle slowely.
G1 E19 F200 ; purge nozzle quickly
G4 P2000 ; Wait for 2000 mSec
G1 E26 F60 ; purge nozzle slowly
G4 P1000 ; Wait for 1000 mSec
G1 E26 F60 ; purge nozzle slowly
G4 P1000 ; Wait for 1000 mSec
G1 E26 F60 ; purge nozzle slowly

G Code description:
http://reprap.org/wiki/G-code