duet3 and e3d ToolChanger and Motion System

Danal

@smece said in duet3 and e3d ToolChanger and Motion System:

that duet3 was more intended for cnc machines like mills and lathes and not really for 3d printers so that duet2 will still be major printing electronics...

The drivers on Duet2 or 3 are OK for desktop CNC. The Duet 3s built in Trinamics that are 24V at 3 or 4A, totalling to just under 100 watts. (and watts are what really matter, both for heat limitations in the drivers and torque in the motors). That will drive Nema17s on a machine that is a few inches in all dimensions, and a very small spindle (CNC needs a lot more force than 3D Print, depending on size of bit, etc.).

Even a medium small 'shop' CNC far exceeds 100W. Example: My CNC Router that is 24x60x5 (inches) runs motors at 70V and 350 to 400 watts. Of course Duet can drive external, like the Geckos, but it seems odd to pay for a board with built in drivers and then ignore them.

Anyway... I'm not sure what Duet/Escher/DC42s ultimate roadmap looks like... but I believe that Duet3, particularly with its tool boards, will be a solid 3D print presence for a long time.

TC

@dc42 Hi, I was planning to use Hemera with Duet Wifi and Duex5. Is there a reason not to do it?

jannau

I'm currently building a E3D tool changer with a Duet 3. A couple of caveats:

wiring kit requires recrimping and motor wires might be replaced
mounting holes are incompatible
sensorless homing will require tuning, I opted to add mechanical end stops for X/Y

I will only use 2 tools until extension board or the tool boards come available. You will need at least one external stepper driver if you want to use the Duet2. 5 internal steppers allow only 1 tool since 4 steppers are needed for motion and the tool changing lock.

A Former User

@jannau thanks

I did not put wiring kit on the list I like to use my own cables and crimp them myself, kinda had it with shitty alu cables and bad connectors
mounting holes for electronics or for something else? wrt duet itself I kinda plan to put it separate from the printer anyhow so this is also not a problem
did not plan to use sensorless homing neither .. I kinda hate how inprecise it is, I'm thinking of making limit switches with piezo disks or I'll go optical, will decide.. but endstops for sure .. real ones

I totally forgot they use one driver for the toolchanger so yes, with duet alone without extension no room for second tool ... now, luckily I have bunch of TB6600 drivers that are stand alone so I can take step/dir from the expansion port directly there, or I can use some of the stand alone drivers I made with TMC2130 that should work too ... or I can use some of the closed loop steppers I have for test, again can go to exp port directly so I think I can manage to get it to run somehow on day one .. issue only is I'm not going to order duet3 till the expansion card is ready for shipment as I doubt duet3d can ship it to me cheap and I kinda hate to pay the shipping and handling twice ... so I'll hack it somehow with duet2eth first and then I'll order duet3 and redo it when times come

A Former User

looking now, duet2 + duex5 is 5+5=10 drivers, duet3+duet3expansion is 6+3=9 drivers, how come the expansion for duet is not at least 4 drivers if not 5 ?

deckingman

@smece Because with Duet3, expansion boards can be daisy chained. So you can add many additional boards and thus very many additional drivers (and heaters,end stops, fans etc).
Edit. And the existing 3 Channel expansion board is the first in what may become a family of expansion boards, depending on demand.

A Former User

@deckingman had no clue, great, thanks

dc42

The reason we chose 3 for the first expansion board is that in a single CAN message we can fit the parameters for 3 stepper drivers.

A Former User

@dc42 said in duet3 and e3d ToolChanger and Motion System:

single CAN message

hm, I missed this, need to go check D3 schematic .. so extension boards for D3 are on can bus, not dir/step like on D2 ? interesting, I always wondered how they sync movement of can bus drivers without a "start / clock" line

dc42

@smece said in duet3 and e3d ToolChanger and Motion System:

interesting, I always wondered how they sync movement of can bus drivers without a "start / clock" line

The main board periodically broadcasts its time (in ticks since start-up, where 1 tick is 1.33 microseconds) and the expansion boards use this to convert the start times of incoming movement commands to their local tick count.

A Former User

@dc42 so you broadcast "local time" so that all modules can sync their time, and you send step commands (start at time X, do Y steps at speed Z ?? ) .. or you fill some "registers" on the dbus client that converts to commands? I have some tiny, tiny experience with MESA cards on ethernet and even less experience with modbus drivers...

dc42

The main board sends the specification of the move. This is the scheduled start time, number of ticks for acceleration, number of ticks at steady speed, number of ticks for deceleration, start speed percentage of top speed, end speed percentage, number of microsteps for each drive, and which drives have pressure advance applied. The move specifications are sent about half a second before they are due to start.

A Former User

@dc42 cool, I'll check out the firmware to see how it works, I should have some time during holidays (for us xmass is in january so tomorrow the party starts and ends in mid-january ) to use to get acquainted, expect questions

anyhow, a friend just surprised me with a duex5 (a prc clone he purchased and never used) so I'm fully covered till duet3 expansion board is ready for me to order them both

one additional question, how does the thermal sensing work on d3 + expansion? I have some semitec ntc's that go up to 300C that I love to use as I know them good and have ton of them (I needed exactly them for some project 9-10 years ago and semitec wanted to sell me only 300pcs and I needed 2 ) so I'm using them everywhere, I think I still have ~50 of them .. I know a lot of ppl go for PT100 but I paid arm and a leg for these ntc's I wanna use them everywhere I can

dc42

@smece said in duet3 and e3d ToolChanger and Motion System:

one additional question, how does the thermal sensing work on d3 + expansion? I have some semitec ntc's that go up to 300C that I love to use as I know them good and have ton of them (I needed exactly them for some project 9-10 years ago and semitec wanted to sell me only 300pcs and I needed 2 ) so I'm using them everywhere, I think I still have ~50 of them

If they are 100K NTC thermistors then reading them up to 300C will be no problem on either the main board or an expansion board.

A Former User

toolchanger arrived, I ordered a duet2eth+duex5 from e3d for now to get everything working and I'll go with 3 when expansions are avaialable .. no motors here need more than 24x2 so I think this will be ok for now

Danal

@smece said in duet3 and e3d ToolChanger and Motion System:

with 3 when expansions are avaialable

Wait for toolboards.

A Former User

@Danal said in duet3 and e3d ToolChanger and Motion System:

@smece said in duet3 and e3d ToolChanger and Motion System:

with 3 when expansions are avaialable

Wait for toolboards.

what are toolboards?

Danal

Toolboards are somewhat like a 3HC expander, except they are physically smaller, and have one of everything. One stepper driver, one heater mosfet, one thermal sensor input (actually, a couple), two fans (heatbreak and part), a few general I/O, and so forth. They are CAN attach.

Therefore, your tool changer can have two power wires, and 4 CAN wires, running to each tool. Instead of 10 or 12 wires.

Tool boards are currently in final beta, to be pre-order in the next couple of months, and general order soon after that.

https://duet3d.dozuki.com/Wiki/Duet_3_Tool_Board

A Former User

@Danal said in duet3 and e3d ToolChanger and Motion System:

and have one of everything.

assumed so but was unable to find the link coooooool ... definetely no reason to rush with d3 order, d2 will get the job done more then adequate and then I can move to d3 ... knowing myself I'm going to now dump my major test system and make something between my cubebot and this toolchanger but so far I dislike the corexy.. we'll see with bit more time with toolchanger maybe it grows on me .. currently my cubebot is operating with 2 independent X axes but will see how corexy shows up in real usage and how this new head changer thingy shows up before I decide to move on to new build... I surely have another 7-8 months to play with it before I can start making anything new (on some huge project attm that's supposed to be done before september, so ideal time to use TC as is without "improving" it ) ...

anyhow what's much more interesting to me is the whole synchronous CAN movements, need to get that out of the firmware, as I had serious issue making something like that (over modbus but same thing) last year for some project, I had to introduce the "trigger" line and changed the "standard" modbus to some ugly custom monster I'm really not happy with.. and it was 2 axes only!!! so I'm stealing the ideas from RRF as soon as I .... (I did take a peek in the source and it's not "my way of doing things" so it will take bit more time to figure everything out but hey.. that's why we do share the source so we can all learn )

A Former User

@Danal hm, who's designing this tool board, I'd love to make some changes :D... I was planning to make one "huge board" out of duet2 + duex5 + "some upgrades" but looking at this concept now I like it more with a ton of can slaves and fewer wires .. but I'd love some "minor" changes to make it more versatile