Another big 3d printer

Hello!
During the last year and a half I have bee studying this forum while constructing and building this big printer as it is now printing, although much of it still are prototypes and in the need of an upgrade and/or change.



The printer is built with MISUMI's 2550 aluminium extrusions and uses a core-xy for movement. However, it moves the printhead in all three dimensions rather than just X and Y. This is to be able to keep the print bed still, since it is 900*900*10 mm and weighs in at about 25+ kg. The Z-axis is drive by two ballscrews each powered by one NEMA 17 stepper motor. Even though this setup uses two motors to drive the Z-axis, i have never had any problems with these getting out of sync. And if they would, it is easy to realign the Z-axis with the buildplate since it rests nice and flat on the corners which keeps the frame together.



The frame is constructed using 4mm thick aluminium corners which keeps it rigid (the table below it moves more than the frame flexes when I apply a force on the top of it). The X and Z axis moves using wheels for the V-slot system. These are not designed to be used with the MISUMI extrusions, but I have found that as long as they are well aligned with the slot in the profile, they stay there and require a severe amount of pressure to move.



I am currently having a print volume of about 800*800*850 mm. When finished it will have an enclosed and actively heated build chamber, but most likely not a heated build plate. As bed material I am currently using a sheet of PIR foam for PLA and a piece of plexi-glass for nylon and ABS (they stick better to this than to anything else I have seen).

If anyone has any comments on the design please let me know I am open to any criticism of my machine.









The printhead is still very much of a prototype and the rods will be changed for a 2040 or 2550 extrusion for more rigidity. However it will keep the dual direct driven extruders, but i might, if it is needed, modify the E3D v6 hotness for water-cooling.



One of the first prints for the new Z-axis.


Hope my English was possible to understand.
//Svensson

Very impressive! Can you post some video of it in operation?

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

Short video of the machine printing:
[youtu.be]

Am I seeing the extruder carriage wobbling back and forth or is that an effect of the fluorescent lighting and the video?

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

The wobble that you are seeing is mostly an effect of the lighting in combination with the rolling shutter in the camera. However the extruder carriage is wobbling a little bit while doing the infills. When designing the thing I did some computer simulations showing that the setup as of now would work, but the simulations didn't match the reality. So I do have another piece of extrusion on its way to replace the round rods, together with a real linear slide. In the ends this piece of extrusion will be held by the same aluminium corners that holds the rest of the frame together.

ABS will stick to PIR. See: [vimeo.com]
As far as I know, PIR will work for any 3D printed plastic because the molten plastic fills and locks into tiny voids in the foam, and PIR won't melt at any 3D printing nozzle temperature.

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

Both ABS and nylon sticks to the PIR foam. However, with this completely unheated build, and the fact that it is currently operating in a garage about 10°C warm, i did find that the shrinking of both ABS and Nylon sometimes pulled the print loose. With the plexi-glass this didn't happen, and the bottom surface came out looking almost like a mirror. But with a heated build chamber, the foam will most likely be better.