Multi-Gantry CoreXY suggestions ?

Howdy!

Kinda new to the whole corexy genre. been playing with "simple" Cartesian printers so far.

I'm looking to build a new printer, I aim to use 3 different materials which are extruded via big and heavy print-heads.

The printed model will be heavy thus my thoughts on a core xy with Z axis bed (double Z).

Because the print-heads are to be heavy and bulky I wish to have each print-head on it's own gantry - and not all 3 on the same one.

So, question is what type of corexy am I looking at here? basically its a 3 gantry corexy, print-heads should work one after the other and not simultaneously.

Because I haven't really built a corexy so far it would be best if any suggestions pop-up regarding an existing design that I can upgrade as needed. or something in that manner...

Thoughts?

Cheers!

You are looking for a tool changer, like this one: https://youtu.be/C4KVxfeMUEw

very cool! but it wouldn't work for me cause my print-heads are way bigger- its not for your standard plastic filament.

No, an exact copy may not work, but yeah, a version of it probably would.

It's unlikely anyone can point you at an existing design that will work because 1) you provide almost no information about what you're trying to do and 2) it sounds like you're trying to do something unusual.

You're going to have to do some design and development yourself.

Don't worry, it won't kill you.

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

You can also build IDEX-style CoreXY printers using either CoreXYUV kinematics or CoreXY + an additional MarkForged style print head. If you want 3 print heads moving independently in X and Y, use CoreXYUVAB kinematics, i.e. three separate CoreXY systems. RepRapFirmware supports all of these as standard, plus lots more variations of CoreXY that haven't been built yet, with a limit of 9 independent axis motors (plus additional Z motors to level the bed if you want them).

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Depending on the relative weight it may be an option to have the bed move rather than the print heads. Other considerations of the possible spacings may determine if the heads can be fixed or moving on a gantry - that way the CoreXY part moves the bed with the heads on a gantry which can be raised with the active print head being moved into printing position and the inactive heads just raised a little to stop dragging

Mike

ok, so I did some home-work and I think I'm looking for a Carthesian (2S2M) - two sides driven by two motors (electrically coupled) printer with Z bed. I'll save the core XYUVAB for the next build David

I've attached an edited cad file based on Divyam C Parmars' "3d printer corexy model all metal" ( [grabcad.com] ).

Basically I need the bed in Z axis because the printed model will be heavy and material is flexible. I'm aiming for 3 bulky and heavy print-heads. lets say each print head might weigh around 2-3 kg. so I'll probably use MGN 9/12 rails for Xs and Ys.

Because I've never really built a printer from scratch I'm looking a suggestions on 'how-to's and fitting for this kind of setup. Any thoughts on motors for this? regarding the firmware, I guess a standard Cartesian with tool offsets should do the trick?


Cheers!

Looks like you are going for a common Y axis and 3 independent X axes. You can achieve that using Cartesian kinematics with the 3 X motors riding on the Y gantry, or Mark Forged kinematics with the 3 X motors fixed (so less moving mass).

Edited 1 time(s). Last edit at 10/12/2019 06:15AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Just an observation. You're going to have a lot of wasted space occupied by the parked gantries.
Belt stacking is also going to be a challenge.

Because of the mass of the head you may be better off using ball screws.
Above and below Y rails could make four gantries possible.
With travelling X motors on the end with the Y nut.

interesting thought, yes that might be an issue.

not sure if totally understand the configuration you suggested.. ball screws I get, not sure the setup you propose.

Sorry for the bad graphic perspective...
2 ballscrews per side. One rail per side on Y axis.
X motors travel on individual gantries.
Probably a more elegant way to arrange them.