4040 Extrusion Zen Coffee Table

In december @mrehorst kindly shared the files of his sand table Arrakis, which I liked to use as a basis for my own coffee table. In the end I redrew all parts to fit my needs, but the fusion files still were a big help, since this was my first bigger project to draw myself.
The table now finally is in a state to show it here, although i will probably still change up the optics. The size is 120*65cm. The main body is made of 4040 extrusion, the sand tray has a frame of 2020 extrusion with two smooth sides, and a bed of 6mm plywood. Additionally I added 2mm white EVA foam for sound dampening
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SK6812 rgbw LEDs are glued directly to the extrusion and are controlled by WLED on a NodeMCU

To have the maximum usable space I mounted the motor to the short side and used pulley blocks in every corner. This way I have a workable bed size of 960x435mm. Also this way I could use a bigger pulley without needing a lot of space. (Please ignore the messy cables. That’s something i still have to work on)

All moving parts are running on UHMWPE sticky table as sliding interfaces. The tension of the magnet carriage can be adjusted by screws. The axis carrier uses some felt as a spring substitute. As magnets I’m using a stack of three 12x12x12mm n52 magnets

Right now I’m using an old Seasonic TFX PSU. The controlboard is an SKR mini E3, which right now is controlled by a Raspberry and Octoprint, though I still want to have a look at Sandipy. Luckily sensorless homing is working fine for me, so i didn’t need aditional endstops. Right now the table can run fine at 100 mm/sec without being to noisy, though at least 150 mm/sec is possible.
The table now is looking like this, although I don’t like it yet too much. I glued vinyl foil to the backside of the glass and added a plywood frame. (The screw holes obviously still have to be covered.) I’m still searching for better ideas.

Finally here are some designs the table drew:

13 Likes

Amazing! Slick build. What about wood filler, sanding down and painting?

Nice build, and it looks a lot better than mine. Now I’m thinking I may need RGB LEDs.

You could paint the back side of the glass, but the vinyl is probably a lot more robust. How do you lift off the glass to redistribute the sand?

I’m planning the outer finish of the sand box to be upholstered with thin foam and covered with cloth as my wood working skills are all but nonexistent. Of course, my upholstery skills are severely lacking, too. It will probably look pretty messy by the time I’m done.

Arrakis is designed so that the drawing is close to the floor, with a deep box so the glass top will be far from the sand. When I run the machine fast it throws the sand and a lot of it will end up on the underside of the glass unless I keep the glass up high. The box forms a skirt that covers the mechanism, legs, and electronics. I’m not too happy about doing it that way because it makes the whole thing look bigger, but I have to keep the Ms. Kitty from getting under the table and chewing on the wires and belts. I’ll probably have to replace the power cord periodically because she’s bound to chew on it like she does every other cord in the house.

I’m convinced the right geometry is a deep basin (like 2") and a wide area between the work area and the leds. The trouble comes when building that cover/frame. The vinyl is a good solution. I would hope paint would be good too.

Very good work. Thank you for sharing your table.