Several Questions on Design Choices

Hello all, first post. I am ramping up to make a V2 (printing parts now), been on my wish list for a long time. I’m prepping to buy several of the other components and had a few questions I’m hoping you experienced experts could weigh in on based on your previous experience.

  1. Control Board: I was planning on using the Pen/Laser Controller from Bart but it’s currently sold out. I’ve been eyeballing the Jackpot as an alternative; I’d like to support Ryan and it has extra capability if I ever wanted to use it for another project in the future. I’m not finding any showstoppers, but am I missing anything that would make the Jackpot a bad match for a ZenXY?
  2. LED Strips: I’m planning on putting in an addressable RGB strip; was planning on a white but like some of the builds I’ve seen here that can have a gradient around the table. Is there a recommended LED density you guys have found looks good (or has anyone found a low density that starts to look blocky)? The planned work are is ~24" x 42".
  3. LED Control: For controlling the LEDs, is this something that can be run in parallel with the single ESP32 on FluidNC? My plan was to run a second ESP32 with WLED, but that’s another board to have in there. I’m doing some more digging here.
  4. Enclosure: I’d like to enclose the bottom of the table for noise, keeping dog hair out, keeping toddlers hands out, etc. Has anyone had issues with items overheating if left running for several hours? Alternate plans are some vents or a machined aluminum heatsink that would extend out of the enclosed volume.
  5. Bottom Plate Thickness: How thick a bottom plate (between the magnet and the ball) have you guys had success with? To try to combat sag I can go with glass (1/4" or 3/8" but it’s expensive, thought I can probably find a used/free mirror around). Alternative is 1/2" to 3/4" melamine, but I’m concerned on the distance for the magnet. Given the size I feared hardboard/HDF would sag too much given the thinner sizes it’s found in.

Any helps you guys can provide is appreciated, I’ve finally convinced the wife after years and stoked to start.

Thanks,
Joel

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  1. I like the len/laser board it’s small and pretty much exactly what the project needs. The Jackpot is a good fit, just a few more dollars. It’s also small, so should be fine.

  2. Density will somewhat depend on the working size, and depend a lot on your tastes. Sorry, I can’t help much here.

  3. WLED is a popular choice, and the ESP32 is small. I didn’t do RGB so I just needed a switch…

  4. I enclosed the electronics, but left the belt and mechanism exposed, because they look cool. Note the motors do.stick down lower than everything else. Generally, the Zen can run at very low motor current, and therefore doesnt generate a lot of heat. The most heat my first (actually beta) build ever gets is the V1pi that runs it. The motor drivers.and motors stay cool. (Motors are set for about 100mA, IIRC.) The one with the pen/laser board I’ve never measured, but the board is stuffed inside an Ikea tabletop. It just has a 2.1×5.5 mm DC jack and the motor and endstop wires coming out near the corners. That one runs patterns that take up to 14 hours to run their course.

  5. As thin as possible. Mine is 1/16" hardboard. Just a little thicker than posterboard. The beta build uses 1/8" hardboard. Magnetic fields dissipate as the square of the distance, so double the distance, a quarter of the strength. 1/8" tempered glass should be able to be quite large and not sag, I’d think. From the performance of mine, I’d not really want to go more than 3/16". I prevented sag in my builds by putting the hardboard under tension. There is an outer frame on the box holding the baking soda medium, which puts stretching force on the hardboard. Not much, but enough. The 1/16" hardboard has stayed flat for a couple years now, and I expect a few more years’ service.

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I think the jackpot makes sense. It is a bit over powered, but it is available and if we can make it standard, it would solve that issue (out of stock, many versions of the pen board).

In my table I used 60 pixels per meter. I like the ws2815, which are individually addressable and are 12V. The wiring is a little bit more complex, but the power only needs to go to one end. The only ones I would definitely watch out for are the ones that keep 3 pixels per controller, so they are only controllable in triplets.

WLED is the way to go. FluidNC won’t be able to match the beauty of WLED anytime soon. And an extra ESP won’t break the budget. There are some other good (I think) design decisions baked into that table, like putting the leds a bit further from the edge.

The only active electronics are the controller and the motors. They are all on one side. As long as you have a smooth running table, you can turn the current way down. So I don’t think heat will be a problem at all. You haven’t mentioned the size you are looking for. If it is a dining room table, you might need to keep the current a little higher, but it will also have more air to cool it.

The bottom plate can’t have any midspan supports. I think glass is best for this. Any thickness of glass that can not break over the span you are looking for is a good thickness. I bought ikea shelves for my recent table. My counter top build uses glass tops from some end tables. I used 3/32" hardboard and it sagged quickly and the magnet scraped in the middle, which sucked.

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Thank you both for your replies, that’s very helpful.

Glad to hear the Jackpot is an option. Given the $15 delta, which is actually closer to $5 since I’d be ordering parts from V1 already and can avoid two shipping charges, seems like the best option for me. My plan is to just take out and store 3 of the 2209s.

I buried the planned table size in the post, my plan is for it to be in the ballpark of 48" x 30" total, with a work area of around 42" x 24". This may change based on what size of reasonably priced glass I can find.

Appreciate your guys’ insight on the LEDs. I figured WLED was the right way, so thanks for the confirmation.

Thanks for your thoughts on the bottom plate, sounds like thinner glass is going to be the ticket for me given the size.

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I’d recommend SK6812 LEDs @ 60/m so you can do both color or ‘proper’ white as the patterns look gorgeous with a nice warm white light illuminating the baking soda. WS2812B or WS2815 are good options too but only do RGB and can only simulate white (cool white).

I connected mine to a separate Wemos D1 Mini (ESP8266) running WLED and ran it all off the same 12V power supply powering the motors and control board. I did need to purchase a large buck converter to drop the 12V supply to 5V for the D1 mini and SK6812 LEDs, which I think came out to ~6 meters total of lights for a coffee table of almost the same dimensions as yours. You might also put a capacitor on the power input for the lights/ESP as the motors can be noisy and cause weird issues without anything to smooth out the power supply.

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I should get some to try out. The white simulation isn’t great with the 2815.

Yeah I find with the warm white version of the SK6812, I can simulate most all versions of white using a combination of the white channel and some of the RGB channels. I just wish they were produced in 12V or 24V as well since you can get a much longer run of them without having to inject power, use smaller gauge wire, smaller power supplies, etc.

I would go with the jackpot imo. I think there will be a lot more input and ppl to help with that one.
I used some thin door skin for my bottom it’s a decent span and sag isn’t a thing for me. I leave mine going for a long time and it doesn’t get warm. And the bottom is all exposed and I haven’t had any issues there either.

Thanks all for the continued feedback.

I came across the SK6812s in my search as well and decided to go with them. Some are offered in a natural ~4500K white along with the warm white and cool white, but went with warm white at the moment, glad to hear it’s worked out well. For the sizes I’m estimating on the table I should be under 5 meters, and given I’m planning a loop my plan is to feed power (5V) from both ends with no injection in the middle. I found one type of 12V RGBW that was addressable on each single LED, it was an SK6812, but not as efficient and quite expensive ($80/5m).

Two power supplies then, one 100W 5V for the LEDs and one 50W 24V for the Jackpot/steppers (cheaper for two Mean Well supplies than a bigger one and a step down transformer). Got an old ESP8266 around I forgot about I’ll use for WLED.

Thanks again for all the insights, if there are any other pitfalls I’m missing please let me know. Waspjr, where did you come across the door skin? Is this just a thin wood laminate (1/8" plywood?) or something else?

For the LED and ESP power, just use a buck converter off the 24V supply. I used this one with mine and it’s driving ~6M of SK6812 just fine and can handle up to 10A: https://www.amazon.com/gp/product/B01M03288J

Thanks, already ordered the 5V power supply as well… it was pretty much the same price as having a larger 24V supply with the buck converter.

I’ve just been waiting for the hardware kit to go back in stock for awhile, think it’s stuck waiting for endstops. I just noticed earlier that there are now Pen boards on sale at the V1 store, so probably shifting from the Jackpot back over… $25 cheaper than buying from Bart on Tindie. Just need that hardware kit (I can source stuff for a good chunk more, would prefer to wait).