Ultimaker Mark2 - The Smart Dual-Extrusion Upgrade

[tinkergnome 927]

45 minutes ago, georgp said:

picks head 2 but then prints everything else with head 1

 

@georgp - if sliced with Cura - it's a combination of two things:

- the start script ends with the first extruder

- for some reason Cura adds it's own tool change command before the start script, but not afterwards

 

I don't know if it is possible to change the start script dynamically depending on the used extruders, probably not.

I think the easiest way would be to add a second printer in Cura (exclusively used for this case) and change the start script.

So that it will only prime (and use) the second extruder.

 

The following is untested, only to give you an idea:

 

G90 ;absolute positioning
M82 ;set extruder to absolute mode
M107 ;start with the fan off
M200 D0 T0 ;reset filament diameter
M200 D0 T1
G28 Z0; home all
G28 X0 Y0
G0 Z20 F2400 ;move the platform to 20mm
G92 E0
M104 T0 S0
M190 S{material_bed_temperature_layer_0}
M104 T1 S{material_print_temperature_layer_0, 1}
T1 ; move to the 2nd head
G0 Z20 F2400
G92 E-7.0
G1 E0 F45 ;purge nozzle
G1 X60 Z0.2 F5000 ; move away from the prime poop
G1 X20 F9000
M400 ;finish all moves
;end of startup sequence

 

[ultiarjan 1,223]

On 2/24/2020 at 11:10 PM, Whom said:

Also just found a great trick using "terrain to STL" and switching the shell extruder to a different colour for contour lines. 

 

NICE! I think I'll steal that idea someday..

[georgp 0]

@tinkergnome

 

Thanks for your quick reply but the script doesn't seem to work. 

It just starts to print with head 1 and doesn't even pick up head 2. 

[navigator 24]

I just use the standard 'single head' um2 profile/slicing within Cura and just mount the 2nd head before starting the print.

 

You just have to take care that the print head remains within the Mark2 area so it doesn't crash into obstacles. 

[georgp 0]

Thanks for your reply. I already tried this but it's just not printing. There is no filament coming out in this case. 

[navigator 24]

2 minutes ago, georgp said:

Thanks for your reply. I already tried this but it's just not printing. There is no filament coming out in this case. 

Strange as works fine on mine 🤔

 

When I get time I'll post my start/ stop gcode bits to see if anything there may help you. 

[georgp 0]

I just tried "normal" cura start and end scripts but it will always print with head 1. 

 

Sorry i just don't get there...

[navigator 24]

Right, I've just checked and running 17.09 firmware on my Mark2 with Cura 4.4.1 and normally just use the UM2+ setup with no problems by just loading Head 2 prior to start the print.

 

Here is my start/stop script I use which may be helpful for you - Gcode flavour Marlin (Maybe it's this that helps? - as can't really see anything else out of the ordinary!)

 

G21 ;metric values
G90 ;absolute positioning
M82 ;set extruder to absolute mode
M107 ;start with the fan off
G28 Z0 ;move Z to bottom endstops
G28 X0 Y0 ;move X/Y to endstops
G1 X25 Y25 F3000 ; bring extruder to the front
G92 E0 ; zero the extruded length
G1 Z0.3 ; lower
G1 X35 E20 F225 ; purge nozzle with 20mm of filament
G1 X45 Y25 F2100
G92 E0 ; zero the extruded length again

 

M104 S0 ;extruder heater off
M140 S0 ;heated bed heater off (if you have it)
G28 X0 Y0 ;move X/Y to min endstops, so the head is out of the way
M84 ;steppers off
G90 ;absolute positioning

 

[georgp 0]

Thanks! No this works!

[hakkattakk 1]

Hi,

 

I bought an upgrade-kit from AliExpress with the Mark2 board. However the "AWG 18 wire" and "Molex cable for the temperature sensor" (I think it's a molex kk 254 cable, but I can't find that anywhere either) was not included.

 

I just cut some wire from another PT100 to use instead of the AWG 18 wire, I guess that should work, but I don't have any cable to put in the temperature sensor input. Are there any benifits to connect these cables at all on the Mark2 board, or can I connect the cables from the print-head directly on the Ultimaker board instead? 

 

This is the kit I bought: https://www.aliexpress.com/item/32827637039.html

 

EDIT: It worked fine 🙂

 

Thanks!

Edited March 3, 2020 by hakkattakk

[Perchik 2]

Any chance you'd be willing to share these JSON files? I'm interested in doing a similar adjustment.

 

 

On 9/3/2019 at 2:04 AM, Whom said:

My new .json file, using only extruder 1

My new file using extruder 1 and 2.

 

 

[Whom 7]

On 3/5/2020 at 6:20 PM, Perchik said:

Any chance you'd be willing to share these JSON files? I'm interested in doing a similar adjustment.

 

 

 

Of course, I attached it but added PDF to the end else it would not upload. I also have a custom start wipe procedure that copies the UM3 and poops a blob directly onto the glass. You have to replace the Mark2 file in definitions so remove the 4.5 from the start of the file name. Let me know how you get on. It's pretty finely tuned to my machine so if you're a few mm different in your home position you'll have clashes. 

4.5 Mark2_for_Ultimaker2.def.json.pdf

[CCA1 15]

On 2/28/2020 at 6:47 AM, georgp said:

I just tried "normal" cura start and end scripts but it will always print with head 1. 

 

Sorry i just don't get there...

I have confirmed this to be true. No matter what you do it will NOT print with just the second head while using the standard Mark2 info. The only way I could get it to work was to allow it to print the skirt or brim with the first head and then and only then will it print the entire rest of the part with the second head.

 

If you know how to change your start and stop scripts, apparently there is a fix that Navigator has provided. I have not been able to confirm this as working for me yet as I have to now search about how to change start and stop scripts when I am using a different G-code flavor.

 

Struggle struggle struggle.  Nothing but struggle at every turn.

[CCA1 15]

On 1/15/2020 at 10:21 AM, dfrez said:

 

Most likely magnets not strong enough. I had the same problem, even with "N52" rated magnets I got from eBay. I ended up buying the same rating of magnet from a more reputable source and they are significantly stronger, even though they are supposed to be the same "rating". 

Annnnnnd now my magnets aren't strong enough to hold the heads together anymore. (sigh) The slightest move towards the back of the machine and the heads separate from the "pressure" of the bowden tube. Worked fine for a while. Not no more.

 

dfrez - Would you be willing to share where you got your "stronger" magnets from?

 

Thanks,

 

struggle struggle struggle

 

 

[CCA1 15]

On 2/28/2020 at 10:37 AM, navigator said:

G21 ;metric values

G90 ;absolute positioning
M82 ;set extruder to absolute mode
M107 ;start with the fan off
G28 Z0 ;move Z to bottom endstops
G28 X0 Y0 ;move X/Y to endstops
G1 X25 Y25 F3000 ; bring extruder to the front
G92 E0 ; zero the extruded length
G1 Z0.3 ; lower
G1 X35 E20 F225 ; purge nozzle with 20mm of filament
G1 X45 Y25 F2100
G92 E0 ; zero the extruded length again

 

Navigator - So, I'm in Cura Preferences and I select my printer "Mark2 for Ultimaker"  I then choose "Machine settings" Inside here I can see:

Printer

Extruder 1

Extruder 2

Under "Printer" I can see at the bottom it sais "Start G-code on one side and "End G-code" on the other. Nothing is under any of it and there is no way to click on it to put anything under it. So that begs the question, "Where do I add the info?" So then I select the "Extruder 1" option. It Appears as though I can add start and end codes here. Great! I copy in the start code you provided. It doesn't ask to save anything so I assume it saves it and then I have to change some setting in Cura so that it asks me to re-slice the project. (otherwise there is no way to re-slice it) I then look at the G-code and there is no change. ?

So I save the project and re-start Cura thinking it needs a re-start after changing this. ..........Still no difference.

 

So, with everything I've done, what am I doing wrong?

 

Thanks,

 

struggle struggle struggle

 

[tinkergnome 927]

36 minutes ago, CCA1 said:

Under "Printer" I can see at the bottom it sais "Start G-code on one side and "End G-code" on the other. Nothing is under any of it and there is no way to click on it to put anything under it. So that begs the question, "Where do I add the info?"

 

"Extruder Start G-code" is the wrong place.

Just increase the size of the "Machine Settings" dialog and click inside of the script frame(s). The script content will "magically" appear by doing this. It's one of several "Cura glitches" IMHO 🤷‍♂️

 

 

vs.

 

 

[CCA1 15]

14 minutes ago, tinkergnome said:

 

"Extruder Start G-code" is the wrong place.

Just increase the size of the "Machine Settings" dialog and click inside of the script frame(s). The script content will "magically" appear by doing this. It's one of several "Cura glitches" IMHO 🤷‍♂️

 

 

vs.

 

 

That worked to be able to see it and apply the code that Navigator supplied. Thank you!

 

However, it still puts head 2 away and prints with head 1? I have it printing with ONLY head 1 in the program. Not only that, my standby temp is being ignored and my material is being kept at printing temp in nozzle 2 while it prints (at printing temp) with nozzle 1. ???

[Whom 7]

My personal solution to all of this was to set a tiny tiny piece to be printed with nozzle 1 which takes 2 seconds, then the main part to be printed with nozzle 2 for the rest of the print

[tinkergnome 927]

4 minutes ago, CCA1 said:

However, it still puts head 2 away and prints with head 1?

 

Just to be sure - you have disabled Extruder 1 in Cura?

 

And don't forget the other details of @navigators method:

 

On 2/28/2020 at 5:37 PM, navigator said:

normally just use the UM2+ setup with no problems by just loading Head 2 prior to start the print.

 

[CCA1 15]

Whom - Thanks for the input. At least this shows it's something others are also struggling with. (or at least did at one time until a "solution" was found) I agree, I found that any printing (i.e. brim, skirt, etc.) done with the first head would indeed allow the second head to print as wanted. But you ALWAYS had to utilize the first head first. I was originally thinking only skirt or brim would work to allow some "pre-printing" but your suggestion of even a little  tiny separate part might be the trick for now.

 

 

[CCA1 15]

3 minutes ago, tinkergnome said:

 

Just to be sure - you have disabled Extruder 1 in Cura?

 

And don't forget the other details of @navigators method:

 

 

Well, I don't know how to disable an extruder in Cura. ??  (Why would I need to? I just tell Cura to use extruder 2 for brim AND part printing)

 

Using UM2+ setup instead of Mark2 will not run my second feeder? How will this then feed the second head?

 

I'm confused....

[CCA1 15]

loading Head 2 prior to start the print

8 minutes ago, tinkergnome said:

loading Head 2 prior to start the print.

 

Why would this work? After copying that code in, one of the first thing the machine does is put head two away?

[henry-tong 2]

Is there a way to use the Mark 2 machine settings and turn off Extruder 2 completely? Currently I do that and it will still start the print by taking extruder 2, priming it and then keeping it at the standby temp as Extruder 1 completes the print.

 

In the past I would simply use the Ultimaker 2+ profile but that doesn't work any longer for me as my flow sensor will no longer work and the print will error out. Simplest solution is to use the Mark 2 machine for all my prints.

 

Thanks in advance for the help.

[tinkergnome 927]

12 minutes ago, CCA1 said:

Well, I don't know how to disable an extruder in Cura. ??

 

There should be a checkbox with the label "Enabled" somewhere...

I use the "Sidebar plugin" - so it may be in a different position than in my screenshot - but it is there.

If only one extruder is enabled (or present), Cura no longer adds tool change commands to the gcode and the pre-selected tool should just stay active.

Personally I don't use Cura for single extrusion prints, but that's what i understood from the posts above? 🤷‍♂️

 

[CCA1 15]

Thanks Tinkergnome. I will look for this. As for my previous post about it putting the head away..... Sorry for the confusion, it appears that I somehow had extra "stuff" in the start script that I copied in. (or added to)  It now does not put the head away and does start as expected. So the new start script WILL work with this scenario.

My next question would be, Do I need to disable this script for "regular" 2 nozzle programs?

 

thanks