Pause to change filament colour?

Adrian52

@blitzreg Yes I do small extrudes from dwc until the new filament is coming through properly, then retrieve dangling filament just before hitting resume. Generally gives a seamless transition.

dc42

@blitzreg, this line in resume.g:

G1 R1 X0 Y0 ; go back to the last print move

should have a Z0 parameter too. But I'm not sure that is causing the problem.

BlitzReg

@dc42 Ok, after it has paused and I change the filament and before I hit resume. I manually click on retract about 2mm. If I don't when it goes to resume it pushes out to much filament at the first start and leaves a glob. If I do a 2mm retract before I hit resume then it comes out perfect.

BlitzReg

@blitzreg my extruder is the Titan Aero with a Volcano. I like the extruder but its a real pain changing out filaments in it and too often when you pull out the filament then the hole gets blocked and impossible to get the new filament back in without disassembly
of the extruder.

dc42

@blitzreg said in Pause to change filament colour?:

@dc42 Ok, after it has paused and I change the filament and before I hit resume. I manually click on retract about 2mm. If I don't when it goes to resume it pushes out to much filament at the first start and leaves a glob. If I do a 2mm retract before I hit resume then it comes out perfect.

Check your pause.g and resume.g files. Generally you should retract in pause.g and extrude the same amount in resume.g, but if you hot end oozes a lot you may need to extrude less than you retracted. Don't forget to put M83 before the retract and extrude commands in case you were doing a print in absolute extrusion mode.

BlitzReg

@dc42

; pause.g
; called when a print from SD card is paused
;
; generated by RepRapFirmware Configuration Tool on Sun May 20 2018 02:01:02 GMT-0700 (Pacific Daylight Time)
M83 ; relative extruder moves
G1 E-10 F3600 ; retract 10mm of filament
G91 ; relative positioning
G1 Z5 F360 ; lift Z by 5mm
G90 ; absolute positioning
G1 X0 Y0 F6000 ; go to X=0 Y=0

BlitzReg

@dc42 Just want to say "Thank you" for all the help! This is my first build and there is a lot to learn! I'm already planning a second build and duetwifi will definitely be in that machine also! Just a great board! I use 3D Printers in manufacturing fishing tackle. I own a fishing tackle company. www.wwfishingtackle.com. Thanks, Larry