So i am also making a coreXY....

Hey! first post here. thought id share my work and get some opinions.

I 've been using a classic prusa i3 design which i made out of item parts and 3dprinted parts, everything works fine now (after a year of improvements ). I managed to print on simplify3d ABS, PC-ABS with great accuracy and success with 3mm nozzle, although i manage to make one part out of 5 due to warping. I have to practically fuse the plastic to a PEI sheet for it not to warp (and then destroy the PEI to remove the part) and again sometimes it still warps.
Therefore as this is my only issue now, i decided to upgrade stuff, and since i like the hobby of building the printer i will build a corexy sort of design from scratch, with end goal to cover the top as well to keep the heat inside.

This is my first finished design of the new printer (the bed will not be mounted like this on the lift, i will have of course screw design for leveling)







features:

- very light head, all based on 5mm bars (okay here i know its thin... perhaps i will upgrade later to 8mm)
- z axis 8mm bars, lead screw simple M6 screw (worked before why not)
- plexiglass 8mm thickness for walls, will support everything there (hopefully)
- all electronics and motors (except extruder) outside of the enclosure

I know this design will probably have a lot of flex etc, but i like the idea of making it, see what happens, and improve from there.

Issues: i need to add a top enclosure.... i could:

1. lower the whole XY so that there is space to flex the filament tube.
2. or add a membrane under the extruder motor somehow? to cover everything from walls under the XY axles and have the extruder tip outside only. that would keep even the belts outside the chamber. I didn't find any shops with membranes for this idea.
3. or create a dome style hard top?

i will try to add a flat top with everything a bit lower, and drive the flex tube somewhere on the side with a "ball" insert on the plexiglass wall to allow the tube to make angles.

Edited 2 time(s). Last edit at 10/26/2017 05:05AM by fuzion.

Interesting, but not CoreXY. Take a look at [corexy.com] to see what corexy is.

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

yeah i know... sort of corexy, i actually mean to have the xy on the head and z on bed.

a small typo, 0,3mm head

If the goal is to print ABS reliably, the machine will have to be fully enclosed and the enclosure temperature will have to get up to 45-50C. That means no PLA parts in the enclosure. How big are you planning to go with this? You may need to have additional heat, beyond that thrown off by the bed, in order to get that warm.

That mechanism is similar to the one used in the Ultimaker printers. Take a look at as many photos of those as you can find to see how they build their machines, and pay attention to the sizes of the parts, especially with regards to the cantilevered bed. Cantilevered beds tend to bounce a lot at the unsupported end unless you make the whole thing extremely rigid, which means thick guide rails or even fully supported linear guide, long bearings, and a big, beefy support structure.

5 mm rails are pretty flexible. Unless this is going to be a very small machine, you might want to consider using larger diameter rails.

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

5mm rods might be OK, but the direct drive extruder will make things worse. Go for Bowden tube extruder, that's also easier to enclose ( with all steppers outside the enclosure).
Some people use aluminum tubing or even carbon for a light gantry. There are special IGUS bearings for carbon, too...

Edited 1 time(s). Last edit at 10/26/2017 02:42PM by o_lampe.

You might want to take a look at HercuLien and Eustathios (Ultimaker style printers) on this google group. There's links to the designs and you might find inspiration and ideas you can incorporate into your design.

Edited 1 time(s). Last edit at 10/27/2017 12:24AM by lars.arvidson.

thanks everyone! i actually had lots of printing issues with bowden style. no proper retract mainly. i saw a huge difference when i went direct. and probably the first change will be the rail diameter.

that group looks helpful indeed.