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Posted · Ultimaker 2 Dual extrusion

Paint them for a test. In serial production you may (partially) anodize them if it works... the amount of radiated heat should significantly more than double up... but maybe you tried that already?

 

...and, how about using a more powerful fan, like this?

http://www.yeahracing.com/catalog/yeah-racing-hacktronic-tornado-high-speed-ball-bearing-25mm-htn304-p-3471.html

Instead of the standard fan's 3CFM, it gives 5.1CFM. Together with anodizing the aluminum parts, the heat dissipation should easily double?

 

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Posted · Ultimaker 2 Dual extrusion

...and, how about using a more powerful fan, like this?

http://www.yeahracing.com/catalog/yeah-racing-hacktronic-tornado-high-speed-ball-bearing-25mm-htn304-p-3471.html

Instead of the standard fan's 3CFM, it gives 5.1CFM. Together with anodizing the aluminum parts, the heat dissipation should easily double?

 

A stronger fan might increase the heat transferred by convection.Usually the amount of heat transferred into air is quite limited. So a stronger fan might not help very much, but it would certainly make the printer louder.

 

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Posted · Ultimaker 2 Dual extrusion

A stronger fan might increase the heat transferred by convection.Usually the amount of heat transferred into air is quite limited. So a stronger fan might not help very much, but it would certainly make the printer louder.

 

Hmm... On the other hand, for some reason Ultimaker chose pretty much the most powerful (and noisiest) more or less mainstream fan which was available. For instance, Papst does not produce equally powerful fans in that size, AFAIK. I came to think of a stronger fan also because of the simulations in this post:

http://umforum.ultimaker.com/index.php?/topic/5953-idea-on-underextrusion/?p=54477

Maybe having more airflow also around the Teflon part would help? One reason why I'm so interested in the topic is my closed printing chamber - where the temperature could (and kind of should) become higher than normal ambient temperature.

 

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Posted · Ultimaker 2 Dual extrusion

hallo een vraagje wanneer kan ik de Ulimaker 2 dual extrusion kit verwachten. :mrgreen:

 

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Posted · Ultimaker 2 Dual extrusion

@scoobydoo apart from the fact that this is an english forum, you might just want to read the full 1.5 pages this topic is long and then you didn't have to pose the question...

 

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Posted · Ultimaker 2 Dual extrusion

I'm not sure there will be an upgrade kit for single extruder UM2. Maybe. Maybe not. Maybe the dual extrusion machine will be called UM3. Maybe UM2 plus. Or UM2 dual extrusion.

Would be really bad news for the UM2 users.. Is this reliable or just an assumption?

 

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Posted · Ultimaker 2 Dual extrusion

It's an assumption after thinking what strategy UM is following with the UM2 (it's not made for tinkerers).

One problem with an upgrade kit is e.g. to keep the CE declaration valid.

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Posted · Ultimaker 2 Dual extrusion

(And it is the alu plates that are conducting heat. They are acting as radiators, and when there are 2 hot hotends in there they have to radiate for both, which they cannot handle)

 

Water cooling!!! :cool:

I might actually be serious.

 

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Posted · Ultimaker 2 Dual extrusion

It's an assumption after thinking what strategy UM is following with the UM2 (it's not made for tinkerers).

i see. maybe true - but as i want to rather do things with my printer than on my printer that's ok for me..

in the end the UM2 is an genius construction.

But dual extrusion was more or less signalized. I still believe the guys as UM will manage it somehow.

 

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Posted · Ultimaker 2 Dual extrusion

(And it is the alu plates that are conducting heat. They are acting as radiators, and when there are 2 hot hotends in there they have to radiate for both, which they cannot handle)

 

Hi Daid. If this is still a problem, and in case nobody's noticed this solution yet, you might pass this idea along...

While staring at my printer just now, I realized there's all kinds of cubic real estate available on the front of the printhead. A new set of aluminum blocks, with a second radiator and fan on the front, with both front and back fans blowing *out*, not in, will not only provide enough cooling but also should help suck some cool air in to the teflons as well, rather than cooling them with preheated air the way we're doing right now.

Just a thought. If the problem's already been resolved, then disregard.

Steve

 

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Posted · Ultimaker 2 Dual extrusion

While staring at my printer just now, I realized there's all kinds of cubic real estate available on the front of the printhead. A new set of aluminum blocks, with a second radiator and fan on the front, with both front and back fans blowing *out*, not in, will not only provide enough cooling but also should help suck some cool air in to the teflons as well, rather than cooling them with preheated air the way we're doing right now.

 

I got this setup ready for testing last night:

http://umforum.ultimaker.com/index.php?/topic/6307-um2-twin-tornadoes/

Now I need to find time to perform some tests...

 

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Posted · Ultimaker 2 Dual extrusion

I think both Kris and 3Poro have done tremendous work toward understanding UM2 hotend heatflow, in particular in regards to teflon temperatures. This work provides a pretty good foundation for improved hotends, whether single or dual, factory or aftermarket.

Kris' thermal simulations are a must-read for anyone thinking of improved teflon cooling.

 

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Posted · Ultimaker 2 Dual extrusion

I just noticed that the estimated realese date for the UM2 dual extrusion kit was listed as "Mid 2014" and now it's "Late 2014".

I don't want to sound like I'm complaining, but REALLY!!!!! That is disapointing to say the least.

 

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Posted · Ultimaker 2 Dual extrusion

Maybe Ultimaker thinks it is better to solve the existing issues with the UM2 such as the feeder problems before bringing a new piece of hardware onto the market which might cause the same issues again and some more in addition. I do.

 

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Posted · Ultimaker 2 Dual extrusion

When I think of the former product description, 2013, before my purchase:

WiFi Ready? / Prepared for dual-head Printing?

In this case, this machine does not even have internal storage for a couple of G-code files. / No useful computer connectivity, this is good only for firmware updates.

And worse, spare parts are unfortunately still not quickly and easily available.

I miss official statements to anyone interested in a simple way accessible, no more and no less.

Markus

 

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Posted · Ultimaker 2 Dual extrusion

I just noticed that the estimated realese date for the UM2 dual extrusion kit was listed as "Mid 2014" and now it's "Late 2014".

I don't want to sound like I'm complaining, but REALLY!!!!! That is disapointing to say the least.

 

Like said above, we could release a broken product right now. But that's not how we do things. We adjusted the estimate as soon as we found out there was a huge issue with the dual-extrusion setup.

I know it sucks. I wished we had all material super printing with a brain interface. But reality is a bitch sometimes.

 

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Posted · Ultimaker 2 Dual extrusion

The problems we are facing for dual-extrusion UM2 are mechanical right now, not software. Due to a mis-calculation the teflon gets too hot with 2 hotends in there.

[...] we found out there was a huge issue with the dual-extrusion setup.

 

Which part of the Teflon gets too hot? Is it the lowermost part of it inside the hollow stainless steel isolator bolt - or the visible part right above the bolt?

When I faced a meltdown due to Pt100 failure, my PTFE part was slightly malformed in the way it didn't fit anymore to the stainless steel isolator properly. It look very much like what Kris describes in this photo: http://picload.org/image/liacpoo/picture_t3.jpg

...of course, in my case the temperature of the nozzle unit got probably a bit out of scale.

I have experimented a bit with additional cooling:

http://umforum.ultimaker.com/index.php?/topic/6307-um2-twin-tornadoes/

If I had a need to cool the printing head further, I would probably add a thermally resistant plate under the lowermost aluminium block (right above the nozzle unit). Now the nozzle unit radiates heat more than necessary to the aluminium block right above it.

 

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Posted · Ultimaker 2 Dual extrusion

Which part of the Teflon gets too hot? Is it the lowermost part of it inside the hollow stainless steel isolator bolt - or the visible part right above the bolt?

When I faced a meltdown due to Pt100 failure, my PTFE part was slightly malformed in the way it didn't fit anymore to the stainless steel isolator properly. It look very much like what Kris describes in this photo: http://picload.org/image/liacpoo/picture_t3.jpg

...of course, in my case the temperature of the nozzle unit got probably a bit out of scale.

I have experimented a bit with additional cooling:

http://umforum.ultimaker.com/index.php?/topic/6307-um2-twin-tornadoes/

If I had a need to cool the printing head further, I would probably add a thermally resistant plate under the lowermost aluminium block (right above the nozzle unit). Now the nozzle unit radiates heat more than necessary to the aluminium block right above it.

 

Exactly that. However, even with "turbo" cooling, the internal temperature is still too hot with dual-hotends. (Pretty much put the large blower-fan of the UM-Original electronics on it to test)

We have an pretty awesome heat-camera that we borrowed from Daniel, makes razor sharp thermal images at close range, which is awesome to help in this aspect. However, every "quick" fix we tried didn't work. So we are looking at more invasive changes to fix this.

 

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Posted · Ultimaker 2 Dual extrusion

We have an pretty awesome heat-camera that we borrowed from Daniel, makes razor sharp thermal images at close range, which is awesome to help in this aspect. However, every "quick" fix we tried didn't work. So we are looking at more invasive changes to fix this.

 

What epsilon do you use for the thermal images of the printhead as it is bare Aluminium?

 

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Posted · Ultimaker 2 Dual extrusion

Daid, Sander, do you think either of you could get a github repository set up for the dual extruder design work, or is that something the community should initiate instead? I know this raises some difficult issues. I think "not yet" is a valid answer, but I also think it's worth talking about the big, smelly elephant stomping around in the room.

I think it's not correct to beat ourselves up over past decisions; we all do the best we can with what we know at the time, and try to learn from that experience. For the current situation, a post-event analysis could go something like this:

 

  1. If the UM2 design had been done as an open project, then we would have seen more people working on dual extruder designs from the beginning, that thermal error would have been caught early, and Ultimaker would probably be shipping dual extruders today.
  2. Paradoxically, the post-production STEP dump enables verbatim copycats, while the file format and timing both prevent the sort of collaboration which would make the UM2 a better product overall (what does a pull request on a STEP file mean?) This combination gives users and the company the worst attributes of both the open and closed source development processes.
  3. A more transparent design process would address these issues, increase confidence, lead to more sales and lower support costs, etc.

As a business owner myself, I know IP-related decisions are scary, fraught with irreversible pitfalls, have implications throughout the business, and are impossible to make in ways that satisfy everyone. I also know that some customers will just never be happy, no matter what you do. :wink:

The question is, should we try a more open design process now? Designing a subassembly like the dual extruder head would be a good test of the process, with limited risk. The other obvious candidate would be a new feeder mechanism, which is already in play and needs to be touched for the second extruder anyway.

 

There are still problems which would need to be overcome -- for instance, file format would need to be something more upstream than STEP, and would probably collapse to openscad or freecad as a lowest common denominator, which I'm sure will make anyone scream who already paid thousands for something more capable. And so on.

Steve

 

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Posted · Ultimaker 2 Dual extrusion

Yes, I want it too ...

I wrote before:

It had a dual extrusion kit can be offered only on an experimental basis, with no functional warranty.

Then, in the end no weeping and wailing.

And better yet, maybe a working solution would be already existent.

Markus

 

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Posted · Ultimaker 2 Dual extrusion

Exactly that. However, even with "turbo" cooling, the internal temperature is still too hot with dual-hotends. (Pretty much put the large blower-fan of the UM-Original electronics on it to test)

We have an pretty awesome heat-camera that we borrowed from Daniel, makes razor sharp thermal images at close range, which is awesome to help in this aspect. However, every "quick" fix we tried didn't work. So we are looking at more invasive changes to fix this.

 

I'm actually rather surprised the 2nd hot-end makes such a big problem, as the original UM2 printing head leaves so much room for quick fixes. One quick fix I made in my hack (which I forgot to mention in my original post) was "burning" the stainless steel isolator:

Printing head assembled

...as you can see, the hollow bolt is not shiny but it's rather dark - which again is good for heat dissipation.

AFAIU, there would be sufficient space underneath the lowermost aluminium block to add thermal insulation. The absorption of radiated heat from the nozzle unit(s) should be possible to bring down quite a bit without major changes.

Also, the contact area between the Teflon part and the stainless steel isolator would be possible to make significantly smaller.

I believe you have tried many tricks already, but at the same time I'm always cautious about "more invasive changes" - as they normally come with side effects.

 

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Posted · Ultimaker 2 Dual extrusion

What epsilon do you use for the thermal images of the printhead as it is bare Aluminium?

 

I forgot, but we black-painted some areas first, because the reflective surfaces didn't give accurate measurements. Then I calibrated the epsilon on a black-painted heater-cartridge.

I'm no longer directly involved in the whole mechanical part (finally) so there is little I can say/do more.

 

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Posted · Ultimaker 2 Dual extrusion

Like said above, we could release a broken product right now. But that's not how we do things. We adjusted the estimate as soon as we found out there was a huge issue with the dual-extrusion setup.

I know it sucks. I wished we had all material super printing with a brain interface. But reality is a bitch sometimes.

 

 

Assuming the recent problems will be solved by the end of the year:

Will the solution be sold as add-on kit for the current UM2 or will the UM2-design be changed?

If I order an UM2 now, will I be able to upgrade it with a secound nozzle later on?

Best regards

Manap

 

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