@Jacotheron Finally had a chance to test this with Fusion 360 and it is working for milling. Thank you!

Saw this posted on reddit and wanted to share:

YouTube link

I'm building a tool-changing printer with two independent z-axes (one for each tool).

The Duet thinks there is only 1 z-axis at any given time, so I use M584 to switch stepper outputs during tool changes.

(dc42 suggested this method here: https://forum.duet3d.com/topic/16609/multiple-z-axis-and-complex-tools-possible)

Is there a way to get each Z axis to move in sync during a print?

For example:

Printer homes and both axes home to their endstops. T0 & T1 Z-height are both at 0

T0 starts the print and completes Layer 1 & 2

Tool-change to T1

T1 Never moved from its homed position (Z=0) so it will crash into the print.

Does anyone have insight to ensure that both T0 & T1 move upward as the print progresses?

Ideally, each tool would move to some intermediate position defined in Tfree, and the return to the correct z-height for printing when it becomes active again.

Thanks!

In the photo, T0 is on the left, T1 is on the right.

Hey, exactly what @Jacotheron said. Here are a couple of post processors found on the forum, but you can search for others too. You'll have to try some out and see what works best for you. If you find one that works, you may also need to manually edit the Gcode to add or remove commands as needed (I have to do this).

I've used this with success:

https://github.com/mwinterm/fusion_post/tree/master/DuetCNC

I tried this but it didn't quite work for me:

https://github.com/guffy1234/mpcnc_posts_processor

Search google for how to import a post-processor into Fusion360

@taconite Hey any thoughts about preventing heat-creep after a (hot) tool is placed back on the carousel?

@JoergS5 There may be hope... I contacted the author of that topic in March and they said the linear rails had been sent off to be EDM'd.

@bot I too have been dreaming about using linear motors in a build. I've heard they can sometimes be salvaged from old electric typewriters from the 80's like the Daisy Wheel or Brother EM series. But I don't know if those are suitable for a printer.

I had an issue like this that was caused by a poor ribbon cable connection between the Duet and Pi. It usually required that I reseat the cable before DWC would work again, but It was also somewhat unpredictable.

I replaced the ribbon cable with some jumper wires and the issue hasn't returned.

@oozeBot

My deviations show -0.117/0.315mm and I get ok results.

Somewhere on the forum I read that larger deviations may require a higher Z-axis acceleration setting so that the printer can move up or down fast enough between probed points while printing. If that's true, then I'd guess that it shouldn't be a problem unless your Z-axis mechanics aren't suited for big velocity changes because of backlash in the z-carriage, etc.

Saw this posted on reddit and wanted to share:

YouTube link

@deckingman

Thanks for the feedback, i've been following your progress now!

I'm still mulling this over and recently came across this video for a 3 in 1 out hotend that looks fairly standard but seems to have some inserts at the end of each heartbreak. I don't know if this set up works, but it seemed strange enough to mention here.

https://youtu.be/P5il1b7b5i8?t=581

I saw this video from Robotdigg and thought it was interesting.

I'm trying to piece together how the printer works. It is not enclosed and the heated bed only reaches 120C.

They print a part in PEEK using an ooze shield and show adjustment of some fan speed during the print. My guess is that they blow hot air on the part, but there's no mention of this in the video or on the product page.

RobotDigg HT Printer

It's clear that they are printing the PEEK in such a way that the crystallinity is low which probably helps a lot with the warping. The part is also pretty small.

even if they aren't using a hot air blower, does anyone think that would be a viable method for printing high-temp polymers?

@oliof How exactly does this work? If I define a virtual axis and then set a position (using G92, I presume) how then do I use that position as a variable?

I've seen people refer to "hidden axes" before.. is that the same as a virtual axis?

@plasticfactory Yikes! I saw your Config.g on the E3D forum. Can you post your latest config.g here?

When I built my TC, I noticed that the E3D-supplied config.g has G10 offset commands for each tool under the M563 tool definitions (with X Y Z = 0). And then the G10 commands appear again at the end of the config with the actual, measure offsets. There's probably a good reason for this, but my config.g just has the offsets set directly under each tool definition.

When you switch between tools using the console (Sending commands T0, T1, etc.), do the XYZ coordinates change to reflect your offsets?

And also, how did you set your offsets? I'd assume that the vernier scale printing would be out of the question if your offsets aren't respected during a multi-material print?

@taconite Thanks for the links!

Also, check out the posts about a TC Delta on this page: https://twitter.com/deltamaker

Does anyone have insight into what is currently out there and whether any designs are viable for color or material mixing?

@taconite Thanks for the reply!

Is the tool-changer "carriage" set up as an additional axis? How does it increment along with the Z-axis?

@oozeBot

My deviations show -0.117/0.315mm and I get ok results.

Somewhere on the forum I read that larger deviations may require a higher Z-axis acceleration setting so that the printer can move up or down fast enough between probed points while printing. If that's true, then I'd guess that it shouldn't be a problem unless your Z-axis mechanics aren't suited for big velocity changes because of backlash in the z-carriage, etc.

@smoki3 Here's the tpost3.g to turn the spindle on:

; tpost3.g
; called after tool 3 has been selected

;ASMBL on
M280 P7 S80

;mesh levelling on
G29 S1

and the tfree3.g to turn the spindle off:

; tfree3.g
; called when tool 3 is freed

;Drop the bed
G91
G1 Z4 F1000
G90

;mesh levelling off
G29 S2

;Drop the brush
G1 A45 B45 F5000

;ASMBL off
M280 P7 S40

;Move In
G53 G1 X304 Y150 F50000
G53 G1 X304 Y180 F50000
G53 G1 X304 Y230 F50000
G53 G1 X304 Y243.5 F5000

;Take a Photo
M98 P/macros/Camera

M106 P0 S0

;Open Coupler
M98 P/macros/Coupler - Unlock

;Move Out
G53 G1 X304 Y150 F50000