It’s beautiful. Well done, sir!
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Backlit, finished perlin noise pattern, and no side lighting.
This pattern has a lot of travel from one spot, and along the edges. It really wore down tracks in the baking soda there.
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A little off topic but what ever happened to the sand table you were supposed to receive?
It is here. In the living room.
Did I miss the reveal?
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Awesome work, it looks super clean!
Now I kinda want to make one too 
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So then in principle it should be possible to make something like a lithophane to render an image, right? It wouldn’t map directly since the average sand coverage can’t be super uneven, but I’m guessing peaks and valleys (wider stepover) would look brighter than a smoother layer of sand (smaller stepover).
Maybe for a simple test, try CAM on a shape with different stepover on the inside and outside. And if that works then a lithophane is possible, although the CAM for that will probably be pretty serious.
It is really hard to predict where the baking sode/sand will end up. It won’t move very far before just bailing and moving around the ball.
For example, if I make a spiral pattern with 1/8" between spirals, I don’t end up with all the sand on the outside. It move some, but it gets saturated pretty quickly and then just puts the same amount on either end of the ball.
If you had a light circle and a dark background, you would need to move all the sand from the circle to the background and you would need to make the background without having deep tracks for the ball.
I think you’re onto something, but it would be a lot of work. This sounds like the kind of job Jamie loves to do 
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I agree, I wouldn’t expect it to be feasible to move the sand large distances. I would be counting on a nonlinear optical effect where thickness is not linearly related to brightness so the average brightness over a zone can be higher or lower even if the average quantity of sand is unchanged. This is something I don’t think is possible with reflected light (even from a shallow angle) because the average reflected light is going to be nearly the same, so you can change the texture but not the overall lightness of different zones.
I just realized I can try this with a ball and magnet in my hand to try this out. Although if it works I will have to build a full ZenXY table for it. And of course the CAM for making the “sandophane”.
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Or you could put some sand in a cookie sheet in your MPCNC and add a ball on a stick to your toolchanger. Then use mortar and spray it when you’re done. Oh, but you won’t be able to backlight it. You will need something transparent.
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This thing about lithophanes reminded me about some experiments I did some time ago with a custom sandify shape.
I added some code to plot images in a sort of “scanned” way. It is not the same level of a lithophane (if I remember I played the elephant drawing on my table but the resolution of the sand was not enough to make it appear properly). Now I know a little bit better how to use react and I see my code was not really the best… Still it may be some sort of a starting point…
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When planning my sandtable I was playing with the idea of using a light guide plate as a sand surface. This could then be edge-lit, so the mechanism wouldn’t cast a shadow. In the end i couldn’t find a sufficiently big defective TV I could sacrifice, so my table now also got the side lighting.
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Yes. I really want this in there, but I wanted it a little different and I am not sure how to fix it . I have to poke at it again. I basically changed it to do the image conversion in an import modal instead, but I never finished it. It has been there a long time. Sorry.
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Really neat design, I’m surprised by how compact the hardware is overall !
What king of control board do you use ?
Now you need to stick a webcam under that desk 
Thank you. I am using a grbl_esp32 board. The tmc pen plotter. I was thinking about trying to mount one from the wall were the bear picture is.
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Jeff, that is a stunning project! Beautiful result, kudos to the team. 
Makes me want to get back in the game and finish my own project 
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I don’t think I see it in here. How high are your lights above the sand surface? It looks like they are about 1" to the top of the strip from the surface the ball is on.
I guess more importantly what height do you think would be good? I am trying to mock something up and wanted to start with an educated guess for them.
I have about an inch total height between the glass. I think the leds are centered about 3/4" up. I can check the cad later if you like.
No that is okay. I am going to grab some lumber right now. Looking like my table will be just under 5" thick if I use a 1" LED bar. I can start with the lights at the top and move them down if needed. I really do not want to go over 5".
Thank you for offering though.
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