Pause to change filament colour?

Adrian52

@blitzreg The line in my previous post is it. I just use dwc, and only have one printer, so I hang around for the pause, then change the filament, and hit resume. I have also used the same method to insert captive nuts. Adrian

BlitzReg

@adrian52 I just ran your line for pause in script. I set it for layer 81. I do have a raft. So, what happened it paused at layer 84 and when I hit resume it left a 1mm gap in between two halfs. Any ideas?

dc42

@blitzreg said in Pause to change filament colour?:

Hi dc42, appreciate the help! So, if you wrote the script what would it look like? to pause at a specific layer height to change out filament? I did like where there was a popup on the screen and showed Z axis and the layer number it was currently on. What I did not like was all the blue boxes popping up on my computer blocking out everything on the duetwifi IP browser control. Changing out filament at a specific layer is where I've been beating my head against the wall!!!! I tried using S3D and make 2 processes with 2 files but the problem is getting them to line up on the Z axis. Please help and show the entire script file you would use to make it do the layer pause. I have an H800 Afinia and there you just punch in the layer numbers you want and it does it automatically. I would be nice if the duetwifi LCD under the pause had this option where you could pick a layer line number to pause at. Thanks again for your help, Larry

I would use Adrian's script,but in front of the M226 command I would insert 'M117 Change filament\n' to display a message too.

dc42

@blitzreg said in Pause to change filament colour?:

@adrian52 I just ran your line for pause in script. I set it for layer 81. I do have a raft. So, what happened it paused at layer 84 and when I hit resume it left a 1mm gap in between two halfs. Any ideas?

Have you tested your pause and resume macro files, by pausing a print and then resuming it?

BlitzReg

@dc42 I just test it and its not working right. I've posted it here so you can look at the pause and resume files.

pause.g

; 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

resume.g

; resume.g
; called before a print from SD card is resumed
;
; generated by RepRapFirmware Configuration Tool on Sun May 20 2018 02:01:02 GMT-0700 (Pacific Daylight Time)
G1 R1 X0 Y0 Z5 F6000 ; go to 5mm above position of the last print move
G1 R1 X0 Y0 ; go back to the last print move
M83 ; relative extruder moves
;G1 E10 F3600 ; extrude 10mm of filament

BlitzReg

@dc42 Looks like in my resume.g its not going right where it left off but 5mm higher

BlitzReg

@blitzreg I may have found the problem. It retracts 10mm at pause and the when it goes to resume there is a ; in front of extruding 5mm back. So when the nozzle starts to print there is no plastic until it catches up.

BlitzReg

@dc42 Ok, the pause and resume .g files are working when I click on the lcd pause and resume. But when the script runs in S3D I'm getting a 1mm gap in between the model. I put the script bellow. Not sure if its a filament extruding problem. Maybe I should prime it more until it comes out of the nozzle.

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