Ultimaker Mark2 - The Smart Dual-Extrusion Upgrade

[gr5 2,172]

@bradley - maybe you should do a screen shot that shows all the temperatures in cura and then show a few lines of gcode that it creates when it primes.  There may be a bug as tinkergonme mentioned.

[bradley 1]

Yes I will when I’m back from my business trip in Europe 

[yyh1002 60]

Hey guys,

Just wondering if anyone's having problem with cura 3.2 freezing.

Both cura 3.2 and 3.2.1 freeze and crash very often if I load and select a very simple model. I didn't had the issue with 3.1 at all.

Since I didn't find any recent freezing report on github, I wonder if it's cause by the altered files for mark2. And this is why I ask here. 

[bradley 1]

On 2/27/2018 at 4:17 PM, gr5 said:

@bradley - maybe you should do a screen shot that shows all the temperatures in cura and then show a few lines of gcode that it creates when it primes.  There may be a bug as tinkergonme mentioned.

 

Ok, I another look and discovered the problem.  It isn't a bug in the firmware.  It's operator error via a missing step.

 

I did not realize that many settings in cura need to set for the individual extruders or "copied" to all extruders.   Upon copying those unshared settings to all extruders, the problem was solved.

 

Thanks to all that commented.

 

*B

[bradley 1]

I am, however, seeing another an issue which I could use some guidance on:

 

The initial priming extrusions seem to get dragged into the model on the first layer.    Any way for the the heads to wipe them/ push them away, rather than dragging them in?   I noticed in the calibration print, there is a wiping motion of extruder 2.   Any way to get that to happen during extruder changes on a live print?

 

Thanks in advance,

 

*B

 

Edited March 9, 2018 by bradley

[gr5 2,172]

What material are you printing?  If you clean the glass well and you are printing PLA then the initial priming extrusion should be fine.  At least it works fine for me with pla - they always stay where they belong.

 

There is a printing kit you can get from UM that has adhesion sheets.  If you cut out a small square of adhesion sheet and place it where the prime poops appear that works for many people.  I'm pretty sure @lrodriguez does this.  There are alternate materials out there like buildtak.

[bradley 1]

3 hours ago, gr5 said:

What material are you printing?  If you clean the glass well and you are printing PLA then the initial priming extrusion should be fine.  At least it works fine for me with pla - they always stay where they belong.

 

There is a printing kit you can get from UM that has adhesion sheets.  If you cut out a small square of adhesion sheet and place it where the prime poops appear that works for many people.  I'm pretty sure @lrodriguez does this.  There are alternate materials out there like buildtak.

 

I'm printing PLA.   You suggest a good idea.  I'll try it, thanks.     I'm finding with each round of tuning, a lot of the issues I've been seeing are going away.    I didn't realize how much tuning I would need to do.   

 

*B

[georgp 0]

Hi guys. I got my Mark 2 setup to work now. I think i calibrated the 2 heads quite well but somehow the 2nd printhead prints some unwanted lines before it is moving to the right position and it's carrying the lines over the building plate which results in inaccuracy. 

Can you tell me if somebody has experienced similar or the same issue. I print with the old UM2 head as 2nd head and the new one from the upgrade kit as 1st head. The feeder and feeder motor are identical. 

Here are some pictures of the prints with it's inaccuracy at some areas. The T-Rex was printed with dissolvable PVA supports. It seems to work quite well at the upper parts but the materials got kind a mixed at the leg parts. Do you thinks this might be an issue of having 2 different heads or is it more due to the settings. 

Thanks for your help!

 

 

[tinkergnome 927]

2 hours ago, georgp said:

somehow the 2nd printhead prints some unwanted lines before it is moving to the right position

 

I'm not sure, if it is the same thing, but Cura always generates a move to the last position of the previous extruder after every tool change. That means: it does actually not "print" unwanted lines, but there are some unwanted travel moves.

If it is this, what you noticed: that's the main reason for the existence of the postprocessing script. Have you used it for the shown prints?

(Extensions -> Post Processing -> add the "Mark 2 Tweaks" script).

[georgp 0]

I did not load that script yet. Will try it the next time. Thanks for your quick reply!

I think it's the issue for the second squirtle print. But not sure if anything else went wrong with the T-Rex. 

 

cheers

[woodpac9 0]

I need some help please I have the Ulta maker to go recently upgraded the feeder to the duel pinch sanbrother sanjiu feeder but I cannot find the settings for the motor

[Glomby 0]

So it appears like I'm still having the problem that Cura uses the standby temp for the second head. I could swear I fixed that, maybe it was with Cura 3.2.

 

I'm using the definition files for Cura 3.2 in the github, which specifically address that issue. Maybe there is a difference between Cura 3.2 and 3.2.1 now regarding this? Or do I need to change my start script now? I don't know.

 

Again I'm on Cura 3.2.1 (not Beta) and the second printhead heats up to standby temp during the priming process, when the print start everything is fine. 

[tinkergnome 927]

20 minutes ago, Glomby said:

Maybe there is a difference between Cura 3.2 and 3.2.1 now regarding this?

 

I don't think so, i use Cura 3.2.1 as well.

 

20 minutes ago, Glomby said:

Or do I need to change my start script now?

 

It depends... if Cura has imported (copied) the machine configuration from an older version, it may be not using the new start script.

You can temporary add a new (fresh) Mark2 machine to Cura and compare the start-scripts. If it doubt, post it here.

 

[Glomby 0]

5 minutes ago, tinkergnome said:

It depends... if Cura has imported (copied) the machine configuration from an older version, it may be not using the new start script.

You can temporary add a new (fresh) Mark2 machine to Cura and compare the start-scripts. If it doubt, post it here.

 

 

Oh you are right, Cura doesn't update the start script. Adding a new Mark2 creates a different script, I changed it just now and will test it with the next print but I'm positiv it is fixed now. Thanks for the swift response.

[georgp 0]

Hi, 

again concerning my T-Rex print from above. I think the main issue is, that the PLA doesn't stick to the PVA. I don't know if it's the filament itself or the settings. 

Do you have any recommendations how to deal with support PVA in Mark 2 software?

 

best, Georg

[rajilpahuja 38]

50 minutes ago, georgp said:

Hi, 

again concerning my T-Rex print from above. I think the main issue is, that the PLA doesn't stick to the PVA. I don't know if it's the filament itself or the settings. 

Do you have any recommendations how to deal with support PVA in Mark 2 software?

 

best, Georg

have you dried the PVA well, if PVA is with mositure it will not adhere to the PLA or any other material its being used for, so please make sure your materials are dried well before printing, the best way is getting a food dryer and putting the spools you want to print with in it  overnight, you might need to see the best temps for different materials, for PVA and PLA i generally use 45C max out, also the other thing is you have to play with the settings for supports, example the XY distance, the Z distance etc, this will be important some materials are ok with two layers difference some three some might like only one, this is something u get by experience and the marktweaks is a very important plugin must install for all with mark2 tool changer, hope this helps

[georgp 0]

I basically just left it on the spoolholder. Didn't know it's that tricky to print with PVA. I already have installed the MarkTweaks. 

Is there any other ways to get the PVA dry by not buying an extra food dryer?

 

cheers and thanks for the answer

[rajilpahuja 38]

45 minutes ago, georgp said:

I basically just left it on the spoolholder. Didn't know it's that tricky to print with PVA. I already have installed the MarkTweaks. 

Is there any other ways to get the PVA dry by not buying an extra food dryer?

 

cheers and thanks for the answer

A toaster oven works too, if it can do 45C, else you can turn up your build plate to 45-50C and leave it on the buildplate for 5-6 hours or overnight whichever you prefer there will be a remarkable difference :) 

[gr5 2,172]

If your PVA is wet you can tell because it kind of sizzles and pops and you can see steam coming out of the nozzle.  And condensed water nearby sometimes.  And the pva comes out snowy white due to all the bubbles inside.

 

If the PVA isn't sticking on top of PLA - well that's normal.  Maybe try increasing horizontal expansion for support.

If the PLA isn't sticking on top of PVA then you are probably underextruding or your two nozzles aren't perfectly level with each other when printing.  It should stick just fine.

 

If you dry it on the bed be careful not to exceed the softening temp (I think it's 82C but I could be waaay off) so put a sample piece of PVA on the plate at 45C for 20 minutes under a towel and then try to bend it and make sure it acts no different mechanically than room temperature PVA.  Again - I think it's around 82C that you'll start to notice it softening so 45C is quite safe but may take many days to dry whereas at 70C it would likely dry much faster (maybe only 5 hours at 70C).

 

I have no experience drying PVA but I've dried Nylon and it takes many hours at 100C.  I think at 45C it would probably take many days.

 

Make sure to put a towel over your spool of filament as it stays hot on the bed to warm up the whole spool.

 

Never leave nylon or pva out when you aren't printing.  Bag them up when done printing preferably with a dessicant.

 

 

[georgp 0]

Thank you guys. I tried the food dryer and calibrated everything from scratch but it still doesn't work. 

Could you guys maybe share recommended cura settings for printing PLA with head 1 and PVA head 2?

 

that's my support material: https://www.3djake.at/formfutura/atlas-support-natural

 

that's my PLA: https://www.3djake.at/extrudr/green-tec-weiss

 

thanks

[rajilpahuja 38]

1 hour ago, georgp said:

Thank you guys. I tried the food dryer and calibrated everything from scratch but it still doesn't work. 

Could you guys maybe share recommended cura settings for printing PLA with head 1 and PVA head 2?

 

that's my support material: https://www.3djake.at/formfutura/atlas-support-natural

 

that's my PLA: https://www.3djake.at/extrudr/green-tec-weiss

 

thanks

I will try to make you a project file, but i don't think atlas is as good as ultimaker PVA, i have some atlas with me, will try and print something that needs a bit of supports

[georgp 0]

That'd be really great!

Yeah, next time Ultimaker PVA!

[zerspaner_gerd 382]

Hello,

 

Does anyone know now where these stupid lines come from and how to avoid them.

 

 

I would be very grateful for the right advice. ?
The previous remedies do not seem to work with Cura 3.3 anymore.

Edited May 11, 2018 by zerspaner_gerd
English picture

[marrincia 0]

Hello everyone,

 

first of all I want to thanks all the contributors for the hard and fantastic work done on the Mark2, really impressive and I am sure in the future this concept of interchangeable tools solutions will become more and more popular!

 

I have tried to read all the forum and I saw a lot of discussion about it and tried to apply various methods suggested, but I still have many problems with power shut-down and I can hardly complete a print..

 

I pre-heat the bed before starting and I have lowered the power to 100W/120W/35W/35W and still have problems. 

The cut seems to happen when the head is moving back for a tool-change (so 2 heater on + bed + max current on stepper? + some fans).

 

I drive my steppers with standard 1200mA. Is there anything I can try before spending quite a bit of money on a new power supply?

 

Many thanks again and sorry for the repetitive topic.

 

Emanuele

 

[bob-hepple 59]

Ok Sorry if this is question is in the wrong section if it is Apologies, I have finally got around to setting up my Mark two software and hardware (Docking ect.,) all went well till I started the code for calibration,  the head ploughed into the Plate,  I had set up the offsets ect for the Z both 1 and 2 heads.

 

I had the mark two working ie swapping heads ect..

 

,,,, when this happened I think the motors slipped when I did a head switch they never married up again,, when I moved the head 1  to the front the cross bar hits the parked head ( sadly this broke the docking mount, so that will have to be re printed) could anyone shine a light where I went wrong??? when the second head was parked should you still be able to bring head 1 to the front without cross bar hitting head 2....

 

Also I tried to do a pid tune on head 1 but this failed it had a target temp of 150, when I watched the screen it got above 180 and then failed saying temp to high,,, Any help appreciated....