Dual extruder V2 is available

The Dual Extruder V2 is available for order! https://www.lulzbot.com/store/tool-heads/lulzbot-taz-dual-extruder-tool-head-v2

The OHAI kit is here: https://ohai.lulzbot.com/project/dual-extruder-v2-tool-head-installation/accessories/

We did some unboxing pics, and have them for sale as well http://i-t-w.com/blog/2016/1/5/lulzbot-dual-extruder-toolhead-v2-unboxing


Looks neat. I don’t suppose anyone wants to sell me a set of the metal bed fingers separately?

If we get some “factory seconds” in I’ll set some aside for you.

Besides printing different types of water soluble supports what else would I want to use this for. I am concerned with webbing when using two different colors in final products. I have seen some dual extrusion prints where the two colors overlap so much it just looks sometimes sloppy.

How is this head new and improved? Also the install seems very lengthy and involved. Is this actually the case or does it just look like it on paper?

Doesn’t look like there was much of a design improvement over the last dual extruder - Which I found to be terrible.

Didn’t come with fans
If you redesigned the thing and added fans, No dual fan support in cura.
Heavy. Too heavy for the gantry smooth rods and a TON of sag
Those thumb screw height adjustments for the second extruder doesn’t work. You will find yourself adjusting it every 5 minutes

Overall, this is very disappointing. As I said in the other thread, $500 will get you much more, and much better. the E3d cyclops and repetier firmware is the way to go. Add the Bondtech extruders and you got yourself a pretty sweet machine!

chriscalandro, I agree most of what you wrote, but I think there are fans included. Look at the black “cover” at the lower side, looks like ducts screwed to two fans.

Right, I just saw that.

So the only improvement is that they added fans.

Nope, change that, They added A fan. If you have ever tried to print pva with a fan, you will know what a pain it is. I would guess at least half of the dual extrude prints you would do would be with PVA - Which means you can’t use this with the fan on, which greatly affects print quality, or you will have to use it with the fan on to print PVA.

Any time frame on flexy dual v2?

  • Hexagon hotends, allowing printing of the great new higher temperature, high performance filaments. They also each have their own micro blower to combat heat creep
  • Aluminum frame eliminates flex and heat warping of the frame
  • Aluminum extruder mount plate eliminated heat warping of the flex plate and serves as a thermal barrier to the extruder to further combat heat creep.
  • Dual filament fans- you can see one sandwiched between each of the cooling ducts
  • Fan ducts on both sides are wired together allowing on/off switching for support materials like PVA without any Cura voodoo.
  • Locking all metal Z height adjuster, which should eliminate the readjusting issue

It’s an entirely different design, with a substantial development and testing behind it.

So I think what chriscalandro is saying there seems to be a single blower which is diverted through two seperate ducts (for each hotend). While this is suitable for dual extrusion of the same material (which theoretically would need the same cooling), the single fan is not suitable for dual extrusion of different filament types because they may need different cooling characteristics.

Can we get confirmation that there are two fans/blowers for the filament cooling?


EDIT: From the BOM for the Javelin on devl.lulzbot.com, there are two Kysan 24V fans. So it looks like the filament fans can be controlled independently making it suitable for multi-filament dual extrusion. Looks like V2 addresses a lot of complaints associated with the original. Good job Lulzbot! On my list behind diapers as a purchase for 2016. :slight_smile:

An ooze shield prints by default to minimize webbing. Cura makes a large retract during filament changes to also minimize oozing. Even the older dual did well with stringing. Here’s a print that just finished on a custom dual extruder TAZ 3 we built https://youtu.be/xFBn5Q1cRTY
Photo below of the finished frog, as printed, no cleanup. Default Cura 18.03 dual extruder settings with .21 layer height, wipe and prime tower and ooze shield diasabled. Note the scale for layer detail reference, this a very closeup picture of a small print that looks great from more than 5" away. Again, this is with the OLD V1 dual.

The physical install of the V2 is straightforward. Alignment is a bit of work. There’s also a learning curve to dealing with creating and managing 2 color models. 2nd extruder support material is easy though.

We’ll have a Dual V2 printing the same model on a shop TAZ 5 soon so we can demonstrate the difference. Stay tuned…

Is there a release date for the V2 Flexy-Dual extruder??

Not yet. One could buy a dual v2, a flexystruder v2, and an additional .6mm nozzle and build one from that.
Or a dual v2, a pair of .6mm nozles, and print a flexy extruder.

The original dual was a complete disaster. This looks to be a tremendous improvement. I have ordered this one and will post my findings. I hope I don’t get burned again for $500

When getting this for a TAZ 4 that has been upgraded to the v2 tool head with v2a connector, will an additional internal blower harness be needed for the second extruder connection or will I be fine just getting the v2c to v1/v2a adaptor?

So… the Dual Extruder V2 came in the mail today. It’s a monster… its looks to be well built upon first inspection. For the most part it looks like it well do well for dual color printing of the SAME filament. Because of the fan duct system, it may not do well in mixed filament prints which require different fan cooling characteristics.

Here’s a picture of the bottom of the extruder:

There are two fans which can be independently controlled. The issue is the fan ducts. Each duct cools BOTH hotends. Ideally each fan would independently cool the left and right side of each hotend.

So if printing different filament types in each extruder, the options are to block one of the duct port so that only one hotend is cooled by the associated fan or to redesign the ducts so they wrap around the hotend… which would make changing the nozzle more difficult.

I have mixed emotions about this. I have the utmost respect for Lulzbot and the engineers. While this seems like a minor over-sight… it doesn’t demonstrate the expertise I’d expect. I hope the folks at Lulzbot re-visit the duct design for the Dual Extruder v2.


I got my LulzBot TAZ 5 Dual Extruder Tool Head v2 last week and have been toiling along in the evenings trying to get it to print nicely. Installation instructions are easy to follow and the calibration squares print nicely and its possible to align the two extruders (in X-Y) without too much hassle. However, the problems start when the print is >2mm tall (Z-axis). Filament from one extruder appears to be blocking the nozzle of the second extruder resulting an incomplete messy print (‘Dual’). As you can see the the gears have dug into both the filaments (‘Filaments’) stopping further extrusion and a complete print. When I print the two colours separately the result is slightly better (‘separate’). Any suggestions would be much appreciated.



Check that your bed is level. It looks like the left side of the blue filament isn’t adhering very well.

Once you do that’ re-check that both extruders are level.

I got mine too. The other part I don’t like about the ducts is they are printed. These are the metal hex extruders and can be run at 300 c. So those ducts are not going to survive. They need to be made out of something else.

Also minor quibble my mount came with a crack where one of the heat inserts was installed and the insert was sticking half way out (the screw pulled it out and there was a gap). Looks like they didn’t get it hot enough and jammed it in delaminating the print. No big deal I can reprint the mount, but that shouldn’t happen to a $500 assembly. Where was quality control? It was very obvious. I noticed it within 5 seconds of taking it out of the box.

Yeah. I thought about the heat from the hotend and the duct. Sadly this may be a shift in the mindset at Lulzbot towards a business conscious approach.

I pay a premium for parts, I expect the engineering and quality. They’ve given us a usable part (at least my dual extruder seems okay… :slight_smile:), its up to the community to modify and improve the part the final 10%.