Ultimaker Mark2 - The Smart Dual-Extrusion Upgrade

[tinkergnome 927]

19 minutes ago, CCA1 said:

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

 

I'm not aware of an easy way to switch between different start scripts in the printer definition.

I would add two separate printers to Cura - one for single extrusion prints and another one for dual prints.

 

[navigator 24]

That's what I do, as stated earlier - use standard UM2+ (Marlin flavour) for single head prints (Head 1 or 2 depending which head is mounted before starting print) and standard Mark2 profile for dual prints.

Only takes seconds to choose between them!

 

[henry-tong 2]

40 minutes ago, tinkergnome said:

 

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? 🤷‍♂️

 

Yes I turned the extruder off and it still uses it. I then went to the machine settings and set the machine to only have 1 extruder and the same thing happens. I'm guessing I need to delete the code manually?

 

I've attached the code for your reference.

MFORU_LEDLampholder1head.gcode

[CCA1 15]

2 minutes ago, navigator said:

That's what I do, as stated earlier - use standard UM2+ (Marlin flavour) for single head prints (Head 1 or 2 depending which head is mounted before starting print) and standard Mark2 profile for dual prints.

Only takes seconds to choose between them!

 

 

So how would my machine know to run the second feeder if I want to run the second head ONLY?? As I stated prior, the Standard UM2+ only knows there is 1 head and 1 feeder. At least that's how I understand it. (which might not be saying much lol)

[navigator 24]

Good question, but I don't know the answer to that one!

Maybe it knows which head is mounted and just uses the feeder for that head but calls it head 1?

 

All I know is that it works fine - presume as it is Marlin being used and not the built in UM2 code?

 

[CCA1 15]

19 minutes ago, navigator said:

Good question, but I don't know the answer to that one!

Maybe it knows which head is mounted and just uses the feeder for that head but calls it head 1?

 

All I know is that it works fine - presume as it is Marlin being used and not the built in UM2 code?

 

OK I tried it. Manually changed the extruder to extruder 2. Wrote out my program using Ultimaker 2 Extended + profile.  (mine shows G-code flavor as Ulitmaker 2 not Marlin)  didn't work.

 

Then changed my G-code flavor to Marlin and it DID work, albeit it ran my carriage into the front left corner of my machine causing my belt to skip a few cogs.

[navigator 24]

You have to be aware of Mark2 space limitations if you have 2nd head mounted, but has never caused me any problems.

Get that sorted - presume it was during priming stage? and you'll be good to go 👍🏻

[CCA1 15]

Yep, During priming. Gonna look into it and see what/where to change that.

 

Thanks

[navigator 24]

Have a look at my script which works fine for my setup  - all depends on how far your head2 sticks out!

Just change the x/y values to suit your needs for prime position.

 

[CCA1 15]

4 minutes ago, navigator said:

Have a look at my script which works fine for my setup  - all depends on how far your head2 sticks out!

Just change the x/y values to suit your needs for prime position.

 

I just looked at the start script and the only measurements for a Y move (I assume this is a Y move, going to the front of the machine? X moves would be left and right?) are....

"G1 X15 Y0 F4000 ;move X/Y to front of printer"

[navigator 24]

I would think you need to increase the Y value - try mine and then work from there: G1 X25 Y25 F3000 ; bring extruder to the front.

 

[CCA1 15]

Yours works much better.  ; )

[yyh1002 60]

15 hours ago, tinkergnome said:

 

I'm not aware of an easy way to switch between different start scripts in the printer definition.

I would add two separate printers to Cura - one for single extrusion prints and another one for dual prints.

 

 

15 hours ago, CCA1 said:

 

So how would my machine know to run the second feeder if I want to run the second head ONLY?? As I stated prior, the Standard UM2+ only knows there is 1 head and 1 feeder. At least that's how I understand it. (which might not be saying much lol)

 

I haven't used the latest Mark2 firmware. I'll share my understanding based on 17.10.1.

The problem with printing with Head 2 only is caused by both the firmware and Cura. 

The firmware takes T0/T1 command and change active extruder without doing switch gesture when it doesn't know head position (head not homed/motor released).

When printing with head 2 only, Cura puts a T1 code to the very beginning of the gcode. The firmware changes the active extruder to Head 2 accordingly, but doesn't actually do the gesture. No matter how many T1 you put in the start code, the firmware already thinks it's holding head 2. Then it start printing with head 1. 

 

The fix is to ask the firmware to ignore any T0/T1 command when head position is unknown.

@alexjx did the trick for DXU firmware based on 17.10.1 Mark2 firmware. 

Line 3658 in Marlin_main.ccp: (The latest UM2Marlin by tinkergnome no longer have this part)

https://github.com/yyh1002/Ultimaker2Marlin-DXU/blob/096c3348782ae575e5ee0e6826900935a1ee8370/Marlin/Marlin_main.cpp#L3658-L3665

    if (!(position_state & (KNOWNPOS_X | KNOWNPOS_Y)))
    {
        // head not homed
        // active_extruder = nextExtruder;
        SERIAL_ECHO_START;
        SERIAL_ECHOLNPGM("Header position not yet known");
        return false;
    }

I then use the firmware with a "smarter" start code in Cura which only involves "initial extruder nr"

Quote

;material_bed_temperature={material_bed_temperature} material_print_temperature={material_print_temperature} material_print_temperature_layer_0={material_print_temperature_layer_0}

M190 S{material_bed_temperature_layer_0}

G21 ;metric values

G90 ;absolute positioning

M82 ;set extruder to absolute mode

M107 ;start with the fan off

M200 D0 T{initial_extruder_nr} ;reset filament diameter

G28 ;home all

T{initial_extruder_nr} ;switch to the first nozzle used for print

M104 T{initial_extruder_nr} S{material_standby_temperature, initial_extruder_nr}

G0 X25 Y20 F7200

G0 Z20 F2400

M109 T{initial_extruder_nr} S{material_print_temperature_layer_0, initial_extruder_nr}

G0 X210 Y20 F7200

G92 E-7.0

G1 E0 F45 ;purge nozzle

G1 E-6.5 F1500

G1 E0 F1500

M400 ;finish all moves

T{initial_extruder_nr}

;end of startup sequence

 

The result is that I have one machine for single nozzle printing of any of the head. It automatically picks and purges the nozzle used. I set up another machine dedicated for dual nozzle print with purging of both nozzles. 

 

[dfrez 21]

On 3/24/2020 at 12:28 PM, CCA1 said:

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

 

 

I bought my N52 magnets from Apex Magnets. 

 

Clicky Click

[CCA1 15]

Thanks dfrez!!

 

They are ordered. ; )  But it sais N48?

Edited March 25, 2020 by CCA1
added info

[Whom 7]

I can never go back to single extrusion example number 4568

Printing face shields for local healthcare workers here in Canada

40 minute print, can't print at night, high manpower demand flipping prints.

Realised that PLA and PETG don't stick very well.

Modified my design to stack with a single PLA layer inbetween.

Bingo! Pumping out faceshields in easily separable stacks.

Mark2 FTW

[CCA1 15]

That's awesome!

What are they doing for the shields part of it?  Just curious.

[Whom 7]

On 3/30/2020 at 9:35 AM, CCA1 said:

That's awesome!

What are they doing for the shields part of it?  Just curious.

Overhead Projector Sheets. I spaced nubs on the shield for a standard North American 3 hole hole punch

[rdekleijn 0]

On 3/29/2020 at 9:03 PM, Whom said:

I can never go back to single extrusion example number 4568

Printing face shields for local healthcare workers here in Canada

40 minute print, can't print at night, high manpower demand flipping prints.

Realised that PLA and PETG don't stick very well.

Modified my design to stack with a single PLA layer inbetween.

Bingo! Pumping out faceshields in easily separable stacks.

Mark2 FTW

 

Looks awesome! how much space did you put between the frames ??

[Whom 7]

37 minutes ago, rdekleijn said:

 

Looks awesome! how much space did you put between the frames ??

I've changed it a bit now as we're up to 3 printers running. A UM S5, UM3 and then the Mark2. Hilariously my Mark2 is doing better than the others hahaha. We're churning out over 100 a day.

There are 2 layers that have PLA in them between each headband. But the second is just the outer edge so that the PETG gets laid down inside this. See image. It is super sensitive to the PLA you use, some stick too well, some not at all, some just peeerrffeeccttt.

 

[rdekleijn 0]

Hi, thanks for your reply!

 

I made a stack of the same model with openscad (with 1mm space in between)

 

with Cura I print with support.

 

Did you use any specific support settings?

 

Roy

[Whom 7]

51 minutes ago, rdekleijn said:

Hi, thanks for your reply!

 

I made a stack of the same model with openscad (with 1mm space in between)

 

with Cura I print with support.

 

Did you use any specific support settings?

 

Roy

No I modelled the PLA and PETG parts manually, this is my own design (because I just had to fiddle!)

1mm is probably more than you need though?

[danielkrice 4]

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

I thought I'd post another update as I've worked through a few issues specific to my use cases. 

 

I've been doing lots of ABS prints in a hot enclosure (70C+), and it seems like my magnets are getting weaker,  losing alignment or I don't know what. I was never able to reach the furthest corners without the head popping off but it got worse and worse. 

 

I modified the head and the coupling to include an additional 4 magnets and printed everything over 11 hours with a 0.25mm nozzle in ABS (fusion+ from Innofil/BASF, it's pretty good!).

 

I also beefed up the coupling to also act as a spacer for the head assembly. What I was finding was that the original design Z height of the coupling was dependant on the top height of the plastic part of the head. And this varied depending on how tight the screws were etc. My modification (which is pig ugly) is captured in the metal part of the head assembly and so is more accurately set over time.

 

It is rock solid now, I think my magnets were crappy but now I've got 7 of them I think there is a nice safety factor. 

 

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

 

One quick question for tinkergnome, why is it that you've set the maximum temp adjust to be + or - 25 in the Mark2 firmware but not in your normal UM2 firmware? Thanks again for the epic work everyone, I could never go back to a single extruder now.  

Hi @Whom,

 

Any chance you could share the modified head and coupling files?

 

Many thanks,

 

[CCA1 15]

I have just noticed that my hot end fan on my second extruder does not turn on when heating up that nozzle. However, my primary hot end fan DOES turn on when only heating the second nozzle OR heating the primary nozzle. I have many hours of dual nozzle printing done at this point, but can not definitively tell you if this has always been the case. (I strongly do NOT believe it to be the case.) Any ideas as to why this would be going on?

 

I have torn down the unit to see if wires were loose either on the fan or the board and it seems everything is nice and tight.

[tinkergnome 927]

13 hours ago, CCA1 said:

Any ideas as to why this would be going on?

 

It depends...
Is this a setup with the optional expansion board or without?
If expansion board is present and connected properly: the matching firmware variant is installed as well?