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Posted · Ultimaker 2 Dual extrusion

A little bit OT:

"Theta" - A printer with up to four heads. And they can print simulaniously. ô.O

Polarkoordinates seems to be a better concept for multi extruder.

http://3dprint.com/13310/theta-3d-printer/

 

One bad thing is, that the resolution changes depending on the position on the build plate.

 

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Posted · Ultimaker 2 Dual extrusion

I was also choosing the UM2 in the promise it was soon be possible to print with two nozzles. And I still hope it will come and that the answer to the problems is not an UM3.

But what I don't get regarding all the temperature discussions. If it's to hot, why not simply turn down the temperature of the other nozzle for a moment - sure, this will reduce the printing speed but I could totally accept this.

So heat up both nozzles to e.g. 180C, then continue to heat up the printing nozzle to 220C, when you switch to the other nozzle, just stop heating the non-printing nozzle.

It's hard to understand that the temperature is a problem here...

Netsrac

 

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Posted · Ultimaker 2 Dual extrusion

I guess the problem is not primarily temperature (intensive quantity) but heat (extensive quantity).

 

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Posted · Ultimaker 2 Dual extrusion

I am off to the London 3d Print show where I believe Ultimaker will be on hand. I will be asking about the dual Extrusion Kit

 

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Posted · Ultimaker 2 Dual extrusion

Since some of their employees already replied here I sincerely doubt that you'll get different information there :)

I'll be sure to bother them somewhat myself when I pass their boot.

 

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Posted · Ultimaker 2 Dual extrusion

What Blizz said. Oh and what dim3nsioneer said ;)

Some more in depth stuff on the heat problem; The warmth with a extra head on a stand by temp (say 170 ish) will increase the temperature of all parts in the head. From what I understood is that a so called heat break is required. If the temperature above the heat brake goes over the glass transition temp, you have a problem. With one hot end powered, you remain well under that temperature. With two, you go slightly over it. And yes, this will probably work when not using PLA (say ABS). But as mentioned before; we're still stuck with a lot of people using PLA, so it has to work for them. If we don't it will cost a boatload of support question and disappointment (and disappointment with people who already spent money is worse imho).

 

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Posted · Ultimaker 2 Dual extrusion

From what I understood is that a so called heat break is required. If the temperature above the heat brake goes over the glass transition temp, you have a problem. With one hot end powered, you remain well under that temperature. With two, you go slightly over it.

 

This part is clear and well described in your posts. Forgive me for insisting, but there's something I don't fully understand... There are a few design flaws in the original UM2 print head which certainly contribute to the problem:

 

  1. There is no heat insulation at all between the nozzle block and the lowest aluminium block. The heat is radiated pretty efficiently over the couple of millimeters gap.

     

  2. The rear fan - not the strongest one - blows forward. Its airflow gets heated by the heat sink before it hits the PTFE isolator.

     

  3. Surfaces which are supposed to radiate heat are not black anodized - and they are smooth.

 

Fixing points #2 and #3 help to convey the heat away from the parts that should be kept cool - but fixing point #1 would actually reduce the need for heating. There are insulator materials which could be placed between the nozzle block(s) and the lowest aluminium block - which would reduce heat transmission from the nozzle unit to the print head significantly. There is also physical connection through the stainless steel isolator, yes, but the radiation component is not insignificant.

What am I trying to say is - if the temperature goes "slightly" above the glass transition temperature using 2 hot ends, I find it strange that particular problem couldn't be fixed without making major changes.

I personally would be ready to accept "known issues" for the first release of dual extrusion.

 

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Posted · Ultimaker 2 Dual extrusion

Like I said before; I only have a limited grasp of the problem. I do know that they did some of the things you suggested, but apparently they are not sufficient (Because if they were, we wouldn't be having this topic ;)).

I do know that one of the concerns is that because the UM2 is much much less a DIY machine, you will need to test your upgrades a lot more (which can easily double or triple the development process). That's why I still recommend the UM original for tech savy users, or those who want to achieve the bleeding edge.

 

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Posted · Ultimaker 2 Dual extrusion

I've been in the market for a 3D printer for a while - UM1 was too early for me but UM2 ticks so many boxes.

I'm no engineer nor have I been up close with the product but I would like to hear from engineers especially, on a scale of 1 to 10, how feasible is it realistically to get a rock-solid solution to dual extrusion to work on the UM2? Does the current layout lend itself to this or is it like trying to fit a square peg in a round hole? Do we have the materials and technology to make this work so that it's just a matter of getting them to play nicely?

I know Ultimaker are doing all they can and I don't mind waiting a little - I'm just looking to make the investment a little more futureproof.

Thanks in advance

 

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Posted · Ultimaker 2 Dual extrusion

As far as I'm aware, the info is old. I don't think aerogels have been considered as heat guard.

On the rock solid side, it really, really depends what you want. Multiple materials? Multiple colors? Is fixing the model afterwards okay? Do you mind if a print can fail because of a cold second nozzle (I've had prints tipped over by the cold hot end)?

That being said; There is no technological reason why this isn't there yet. But there are so many points of failure and a whole range of posibilities on how to fix them. Its a 'simple' matter of finding a set of configurations / options that fixes these problems (The problem overlaps with software (Oozeshield, wipetower, heat / cool down procedure, calibration), hardware (raising hotends, plugging them to prevent ooze, switchable hotends, etc) and material (Make material ooze less, change material so it prints better, etc).

 

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Posted · Ultimaker 2 Dual extrusion

I know a ton of things can go bad from the moment you have 2 nozzles working on the same head but I was under the impression that as far as the UM2 was concerned issues were still about hardware and mostly about not spreading heat from one nozzle to the other. I might have missed a few posts here and there.

And yes the news about aerogels is not news but some are a lot more resistant than what they used to be therefore making them potentially better suited.

 

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Posted · Ultimaker 2 Dual extrusion

Wait!..... NOW the software is a problem too? :)

You know what would be cool.... posting some more positive results of hurdles that have been overcome. It's just flat out depressing that every time I check this forum every other week or so, that more and more problems are listed, and no good news. I'm trying to think of any good news and I can't remember any off the top of my head. Will have to go through all 7 pages again and see if I can find any.

Also, could you coat the inside of a metal extruder with teflon (similar to a frying pan) I mean, low friction, nothing sticks to it, very high heat. Surely someone has though of this, so there must be a problem with that too?

P.S. Squeek Squeek

 

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Posted · Ultimaker 2 Dual extrusion

If heat conduction is a problem, would using an aerogel insulation blanket directly above the heater block fix the problem, or would a solid plate of about ~5mm thickness be better?

I found a cheap potential solution, Pyrogel-xt blanket , is it worth a shot to try it and DIY dual extrusion?

http://www.buyaerogel.com/product/thermal-wrap-tw350/

 

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Posted · Ultimaker 2 Dual extrusion

damn, i didn't see this thread, i buy the ultimaker 2 for the announced dual extruder. :(

any news ultimaker team ?

 

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Posted · Ultimaker 2 Dual extrusion

If heat conduction is a problem, would using an aerogel insulation blanket directly above the heater block fix the problem, or would a solid plate of about ~5mm thickness be better?

I found a cheap potential solution, Pyrogel-xt blanket , is it worth a shot to try it and DIY dual extrusion?

http://www.buyaerogel.com/product/pyrogel-xt/

 

Wasn't the conclusion about aerogel that the maximum operating temperature was something like 100C? I know this was talked about a few pages back. And most heat is conducted trough the metals, air is a horrible heat-conductor anyhow.

 

damn, i didn't see this thread, i buy the ultimaker 2 for the announced dual extruder. :(

any news ultimaker team ?

 

Latest news is that the R&D team just moved to a new building, so we are no longer sitting with 4 people in an office fit for 2. And, that we're working on the dual-extrusion, as well as looking into what is the best soluble support material.

I'm actually being pulled off Cura development to assist on dual-extrusion.

 

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Posted · Ultimaker 2 Dual extrusion

I'm actually being pulled off Cura development to assist on dual-extrusion.

 

If this doesn't mean dual extrusion gets the absolutely highest priority... !?! :eek:

 

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Posted · Ultimaker 2 Dual extrusion

thanks for the answer Daid, good idea ot research on soluble material. glad team moving on a bigger place.

i believe soluble material on support with 100% infill is the way to get full quality everywhere.

 

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Posted · Ultimaker 2 Dual extrusion

Well 100% infill would probably be overkill but as long as every side/top/bottom touching the other material has a well made surface it should provide a good result.

In the mean time, I use wet sanding on PLA more and more. Most of the time, big overhand with supports can come out pretty nice to the touch.

 

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Posted · Ultimaker 2 Dual extrusion

Wasn't the conclusion about aerogel that the maximum operating temperature was something like 100C? I know this was talked about a few pages back. And most heat is conducted trough the metals, air is a horrible heat-conductor anyhow.

Latest news is that the R&D team just moved to a new building, so we are no longer sitting with 4 people in an office fit for 2. And, that we're working on the dual-extrusion, as well as looking into what is the best soluble support material.

I'm actually being pulled off Cura development to assist on dual-extrusion.

 

Nope, the Pyrogel-XT blanket is rated for industrial use up to 650°C/1200°F and I was thinking about the 5mm thick version.

 

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Posted · Ultimaker 2 Dual extrusion

This part is clear and well described in your posts. Forgive me for insisting, but there's something I don't fully understand... There are a few design flaws in the original UM2 print head which certainly contribute to the problem:

 

  1. There is no heat insulation at all between the nozzle block and the lowest aluminium block. The heat is radiated pretty efficiently over the couple of millimeters gap.

     

  2. The rear fan - not the strongest one - blows forward. Its airflow gets heated by the heat sink before it hits the PTFE isolator.

     

  3. Surfaces which are supposed to radiate heat are not black anodized - and they are smooth.

 

Fixing points #2 and #3 help to convey the heat away from the parts that should be kept cool - but fixing point #1 would actually reduce the need for heating. There are insulator materials which could be placed between the nozzle block(s) and the lowest aluminium block - which would reduce heat transmission from the nozzle unit to the print head significantly. There is also physical connection through the stainless steel isolator, yes, but the radiation component is not insignificant.

What am I trying to say is - if the temperature goes "slightly" above the glass transition temperature using 2 hot ends, I find it strange that particular problem couldn't be fixed without making major changes.

I personally would be ready to accept "known issues" for the first release of dual extrusion.

 

If the next big announcement isn't the dual extrusion upgrade, then I will try out the Pryogel-XT blanket for myself, because if it does perform as well as advertised, and possibly added in conjunction with installing a small fan infront of the print head to reverse the airflow, than it would be a very cost effective solution. The blanket costs $30 for a 30cm x 30cm x 5mm square and can handle extreme temperatures

 

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Posted · Ultimaker 2 Dual extrusion

If the next big announcement isn't the dual extrusion upgrade [...]

 

I would be surprised if dual extrusion upgrade was announced anytime soon. I believe there are problems with the current print head design in case of high print temperatures (printing something else than PLA) - not to talk about additional challenges related to having two extruders. The PTFE material was changed recently, but the new material doesn't seem to solve the problem - it still wears off fast with ABS.

At the moment it might make sense to have the two extruders simply dedicated to different materials - the current design for PLA and some "all-metal" design for ABS/PC/etc... However, Ultimaker has much more ambitious targets for the dual extrusion launch.

 

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Posted · Ultimaker 2 Dual extrusion

i try to understand the issue for my personnal culture (i'm totaly newb in 3d printing) :

two heads carry to much heat so it will hard to contain a good temperature for pla, is that ?

 

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