Jump to content
Ultimaker Community of 3D Printing Experts
Sign in to follow this  
aperturist

Dual Extrusion Queries

Recommended Posts

very interesting, that nearly no replies are coming if one asks for special things bout UM2 double extruder. Ok I see, nobody is running one cause commercial versions still don't exist. I wonder if a tinkerer got something to run yet.... UM staff is telling that there is some progress and they plan to release something in 1stQ15. We hope the best....

 

Share this post


Link to post
Share on other sites

I have the same feeling, having seen some dual extrusion printers in action like the makerbot replicator 2x and seeing the result convinced me that it's better to wait for something that actually works flawlessly instead of having it quicker and work partially.

 

Share this post


Link to post
Share on other sites

Soluble support material. Currently there are 2 real options that people are trying to use:

1) PVA

2) HIPS

Let me talk about HIPS first. First of, it's a styrene. Printing it gives off styrene gas during printing. Wikipedia can fill you on in the details of that: http://en.wikipedia.org/wiki/Styrene#Health_effects

Limonene needs to be used to disolve HIPS after printing. Which is a biological turpentine. Nasty stuff that needs special storage and special handling.

So. HIPS? Not really something we to do as Ultimaker, as we like our customers healthy.

PVA. Great on paper. As it dissolves in water. No nasty chemicals. Prints nice. Sticks well to PLA.

However. 2 problems.

Problem 1 "Crosslinking". This is the effect where PVA turns into carbon chains at temperatures. PVA seems to degrade and the older it is, the easier it crosslinks into carbon, blocking your nozzle. Pretty much requiring you to drill out the nozzle or buy a new one. Pretty annoying, as we haven't found the parameters yet which cause this. Rolls that print fine the first day, cause problems the next day. Right now, it's pretty much "once you get it out of the bag, you have 12 hours, after that it's danger material".

Problem 2. This stuff is soft at low temperatures. 35C it's soft. With the feeder wheel reaching 35-40C during normal operation, the PVA grinds very easy on retractions.

Bonus solution:

PLA does get soft at 100C. So if we would have a 2nd material that is still 100% stiff at 100C you could use PLA as support and the other material as build material. This is just an idea that we haven't tested yet.

 

Share this post


Link to post
Share on other sites

Interesting thanks for the information Daid.

So basically before even wanting to have dual extrusion (soluble supports is the only real utility for me), we have to wait for someone to develop a reliable and usable soluble material... Colorfabb maybe? :mrgreen: Or is Ultimaker also doing research on soluble materials?

 

Share this post


Link to post
Share on other sites

Or is Ultimaker also doing research on soluble materials?

 

Where did you think the above information came from? Yes. We're looking into this. It's the main use for dual-extrusion right now. But we haven't solved the problem. (We are working with 3th parties, but sharing who those are isn't my place to do so)

Another use for dual-extrusion could be mixing 2 different materials in 1 print. Flexable materials could be interesting. But what I really hope for (but haven't seen yet) is a properly conducting filament. Not the 10kOhm/cm material that you can get right now. As a well conducting material would make 3D circuits possible. The material available right now can only be used for touch-sensing goals.

 

Share this post


Link to post
Share on other sites

I think it will take quite some time before we'll see "conductive enough" filaments - unfortunately. Until then we'll have to stick to copper paint (http://umforum.ultimaker.com/index.php?/topic/3803-ultimaker-2-dual-extrusion/?p=73337). Especially under-extrusion problems and conductive filament don't really play well together.

How about using polycarbonate, PLA and a pressure cooker? http://en.wikipedia.org/wiki/Pressure_cooking

 

Share this post


Link to post
Share on other sites

Are you allowed to tell with which parameters you printed the PVA?

 

Single extrusion. UM2. Tried various temperatures, depending on the type of PVA (we got different possible suppliers, which need different settings). I didn't do most of the tests, so I do not know the exact details, but I know various different settings where tried. These where not simple one off tests, quite extensive testing has been done, and no solution for the crosslinking problem has been found by varying the settings.

 

Share this post


Link to post
Share on other sites

T0=170°C?, Tbed=60°C? That's about it, isn't it?

If that is what the supplier recommends, most likely, yes. PVA is tricky material, and I would regard it as highly experimental if you have some. So you will have to play with it to find the proper settings. Start with what the supplier recommends and go from there. But I cannot say "if you use settings X it will print nice"

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Our picks

    • Taking Advantage of DfAM
      This is a statement that’s often made about AM/3DP. I'll focus on the way DfAM can take advantage of some of the unique capabilities that AM and 3DP have to offer. I personally think that the use of AM/3DP for light-weighting is one of it’s most exciting possibilities and one that could play a key part in the sustainability of design and manufacturing in the future.
        • Like
      • 3 replies
×

Important Information

Welcome to the Ultimaker Community of 3D printing experts. Visit the following links to read more about our Terms of Use or our Privacy Policy. Thank you!