TAZ parallel printing

We’re working on another dual extruder modification and have a hacked up prototype for you to try out. Parallel printing involves mounting a 2nd extruder and feeding both the same print commands. You end up with twice the parts printed in the same amount of time, which is great for anyone like us who is making a lot of something

Our simple hack allows you to mount a 2nd extruder 100mm along the x axis from your normal extruder. After loading the dual extruder firmware (here— > http://devel.lulzbot.com/TAZ/Dual_Extruder-TAZ/Dual_Extruder-V0.75/), you can control the temperatures of the nozzles individually in pronterface (switch between extruders by sending T0 and T1 commands). You can then print from g-code made for a single extruder with a bed size of 125x280. The extruder motors are wired in parallel, so they need to be fairly close in their extrusion rates.

I’ll have a full write-up soon, but here’s a quick parts list and some pictures to get you thinking.

Printed parts:
1 single bearing holder
1 x carriage
1 extruder mount
1 x-carriage guide

3 M3x12 bolts
15 M3 heat set inserts
3 m3 washers


This is looking great!! How long until a quad-struder? :wink:

This is just fantastic. It looks really easy to set up. Quick way to double production! :slight_smile:



the quadstruter has some merit, using 1013s dual setup it could be possible with some creative wiring

How do I wire this so that it receives the same signal? Is it just cloning the first or do you have to change the gcode or something? Do you have to worry about exceeding the amperage of the stepper driver?

You should be able to just splice the two hot ends and Extruder stepper motors in together, so they move as one.

I was just wondering if it the total current draw would be too much. Not so much worried about over loading the circuit as I am dividing the total current between two. I’m assuming there were no issues with the torque needed to extrude.

I was really looking to make this work for my Taz 5, can anyone help me out as the link as listed above: http://devel.lulzbot.com/TAZ/Dual_Extruder-TAZ/Dual_Extruder-V0.75/ no longer works?

Here’s the current directory: http://devel.lulzbot.com/TAZ/accessories/dual_extruder/parallel_printing/ You should be able to get the bearing mounts from your sdcard.

I’m curious to see how much the extra weight/momentum affects the prints. Are surface quality & dimensional accuracy compromised using the same speeds that you would with a single extruder?

What about feed variations from one hobbed bolt to another.

We find that with the new tool heads, the hobbed bolt/Estep variations are rather minimal.

Can you do this with the dual extruder and the software used for that?

I have been looking for a gcode that will tell it to activate T0 and T1 at the same time but everything I have run into so far says that gcode is based of singular tool operations.

How did u get the second extruder to mimic the first one all I need is for it to send the same extrusion commands not the movements since the heads are connected and will be moving as one unit

Heya, finally had some time to get back to this and have hacked together an updated version for my TAZ 6! I’m calling it the twoolhead. Get it? Like TWOolhead? I’ll show myself out…

Here’s a video of the startup sequence, I apologize in advance for the vertical filming and commentary: https://youtu.be/lPKugOK1ME8

Source for all the custom bits is available here: https://github.com/coloradoprintingproject/twoolhead, the rest of the parts are stock components from the latest mini toolhead available here: http://devel.lulzbot.com/mini/accessories/dodo/

Aside from the obvious update to hexagon hotends and a newer extruder, this updated version uses the same mount as the rest of the TAZ accessories so you don’t need to dismantle the whole x axis to install the thing. Also it’s using separate stepper drivers (E0 and E1) to drive the two toolheads instead of just splitting the E0 circuit like the original prototype did.

Pretty stoked on how this turned out, I’ll post progress as it’s made :slight_smile:



It’s definitely possible with the current dual, but you’ll be limited to pretty small parts. There isn’t a gcode command for that, you’ll either need to modify the firmware or the wiring (or both).

On the original prototype the 2 extruder steppers were just wired together in parallel, so no firmware tweaking was needed. On the latest build a friend of mine helped me get the firmware to just send the same command to both steppers by creating a PARALLEL_PRINTING definition in the firmware. TAZ 6 firmware is posted in my github repo (https://github.com/coloradoprintingproject/twoolhead), I don’t currently have firmware for anything other than the TAZ 6.

Hope that helps

Very cool! nice work!


I’ve made a bit more progress on this, files are up for a stiffened version of the twoolhead. mmm beefy.

Here’s a video of the actual printing, it’s running basically stock high speed profiles with the acceleration turned down to 400mm/s^2 (not sure if this is needed or not)



Following up with a long overdue update!

Over the last few months I’ve iterated a whole lot and produced lots of twin parts. The 3rd generation twoolheads are performing well on both TAZ 5 and 6’s.

I’ve also started a company called the Colorado Printing Project dedicated to developing open source production printing technology, and am pretty stoked to announce that in the near future I’ll be crowdfunding a limited release of twoolheads through Crowd Supply! Hopefully the twoolhead will be the first small step in a long journey toward 3D printing being a more serious option for mass production :slight_smile:

Please follow along with the campaign if you’re interested: https://www.crowdsupply.com/colorado-printing-project/twoolhead

twoolhead install walkthrough