Duet with Hotend breakout boards

ericlmccormick · 2 Oct 2020, 15:55

I know the duet boards are designed to work with many different setups but many people use them for 3D printing. One of my biggest hassles is running all the wiring from my hotend back to the board. I would be nice it there was a variant that instead of placing everything on a single board, you have the components that go with a hotend on a breakout board. Then you would buy the main board the controls the stationary items and then add a breakout board to go along with each hotend you have. Then you would have a single ribbon cable that you could cut to length and have a clean setup. In addition to cleaning things up, this would reduce the hassle of breaking up wire bundles when you have a failed part. If you can make everything on the breakout board a screw down terminal, then it would save a lot of time trying to make and test short run cables, especially if those wires are only 5cm long. If you make a large system, you are not having to extend 7+ cables, just 1 ribbon cable. If you have a stepper motor upgrade you can just replace the breakout board and not the whole system. By having the extruder stepper controller on the breakout board you can make the main board cheaper instead of guessing how many the end user will want.

The main board would consist of
X, Y, Z1 Z2 steppers (4pin)
X, Y, Z1 Z2 end stops (3 pin)
H0/1 (bed/enclosure) Heater (2 pin)
H0/1 Thermocouple (2pin)
Case fan(3 pin)
Enclosure fan(3pin)
4 to 8 breakout headers

Breakout board would have
ExStepper - 4Pin
ExHeater - 2Pin
ExTemp - 2Pin
X and Y endstop (redundant) - 3Pin
ZSensor - 5pin (Pin + 3 Pin) for support BL Touch
Part Fan - 2Pin
Heater Fan - 2Pin

You could also have a lighter weight breakout board that has just a stepper, heater, temp and fan for those with multiple tool heads or where end stops are not on the tool head.

Luke'sLaboratory · 2 Oct 2020, 16:00

Duet 3 with CAN 1LC toolboards might be your ticket then. I'm sure there will be new, cost-effective units that include CAN as well that you can pair with the 1LC toolboards in the future. These boards break everything out into seperate units for "just" that component, and i'm sure there will be plenty of other variants that any person can use to build a super-flexible network of modules.

As for just wiring concerns, - I'll self promote (mods, feel free to nuke if not cool) and offer my dumbboards as an option - I use them on my toolchanger build and I think they're neat!
https://www.lukeslab.online/shop/dumbboardv1 -
(Molex Microfit)
https://www.lukeslab.online/shop/dumbboard (IDC ribbon cables)

ericlmccormick · 2 Oct 2020, 16:08

That looks perfect. Now they just need to make a Duet 3 lite where the main board isn't doing as much of the heavy lifting.

Luke'sLaboratory · 2 Oct 2020, 16:14

It definitely seems there's a good amount of opportunity moving forwards for splitting out the controller PCB's into whichever direction is needed! the difficult part will be deciding which configs to support first - I'm a big fan of triple-z lead screws so i'd definitely want 5 drivers just for the "main" board, but many only use one driver for z, so they'd want a smaller "main" board. So many configs!

dc42 · 2 Oct 2020, 16:15

The Duet 3 Mini 5+ will support up to 7 drivers + CAN. https://forum.duet3d.com/topic/17409/duet-3-mini-5-initial-announcement

Luke'sLaboratory · 2 Oct 2020, 16:23

@dc42 said in Duet with Hotend breakout boards:

The Duet 3 Mini 5+ will support up to 7 drivers + CAN. https://forum.duet3d.com/topic/17409/duet-3-mini-5-initial-announcement

Aha! I guess I wasn't up to date! Didn't know it also supported CAN, glad to see its been added

ericlmccormick · 2 Oct 2020, 16:28

I forgot about triple Z!
Duet Mini announcement says it won't have CAN so it won't work with 1LC toolboard.
Need something where the main board + 1 toolboard is similar spec and priced of a Duet 2 wifi
Any chance of a header that gives the Duet2wifi and Duet2Maestro CAN ability so that the toolboard can be used on those systems?

Luke'sLaboratory · 2 Oct 2020, 16:30

@ericlmccormick
DC42 designed the board - The initial announcement says it does, but further updates down the chain post the revisions and says it now supports CAN (which is what I didn't know until re-reading the chain - thanks @dc42 )

ericlmccormick · 2 Oct 2020, 16:30

@ericlmccormick I see further down that CAN has been added

T3P3Tony · 2 Oct 2020, 16:40

@ericlmccormick said in Duet with Hotend breakout boards:

Any chance of a header that gives the Duet2wifi and Duet2Maestro CAN ability so that the toolboard can be used on those systems?

No unfortunately not.