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Marble Fountain

willmorrison.net

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61–70 of 97 posts

Re: Marble Fountain

#61

Post by WillMorr »

titanomachy wrote: post #51

The particle simulation approach to generating an organic "tree-like" support structure is super creative! If I'm understanding correctly, you defined some laws of physics and then ran a simulation with the "time" dimension mapped to the z-axis? Is this a well-known approach, or something you came up with? Either way, it produces a beautiful aesthetic. I'd love to play around with this idea.

That's pretty much it! It's the simplest method of supports I could come up with that allows for robust keepout zones. I did have a bunch of issues at first with supports blocking the path but with a little tuning it became surprisingly consistent. I doubt I'm the first to come up with it but I have not seen any similar systems.

Thank you! The emergent forms are much more interesting than they have any right to be for such a simple system.

Re: Marble Fountain

#62

Post by WillMorr »

bix6 wrote: post #40

Super cool! I would love to see a white / clear one with LEDs. Rainbow road :)

I've actually done clear prints with LEDs installed. The bottom is much brighter than the top and it just look kinda tacky. I briefly hollowed out the supports and tried running fiber optics but it didn't help much.

I'm realizing now that I tried a lot of weird shit during this project that just did not work at all or make it into the final product, I should do another video just of all my failed abomination marble runs.

Re: Marble Fountain

#63

Post by WillMorr »

fogleman wrote: post #59
WillMorr wrote: post #34

Earlier quoted context omitted.

It's specifically using SolidPython2 to generate the models. I originally wanted to do a quick code cleanup and have the specific math be much clearer but by the time it was working that was an absolutely massive undertaking. If I touch the code again I'm probably going to refactor the entire codebase and use a different 3D engine.

What did you not like about the SolidPython2 / OpenSCAD approach? What would you want from a different "3D engine" for this?

Mostly speed, I'm mostly doing large boolean unions of primitives or chain hulls and OpenSCAD chugs pretty good at large numbers of operations. Don't get me wrong, they're great tools for what they're good at. I need to do more research before I start a port, SDFs seem like the best option but I'm not 100% confident. I am considering using your SDF library though (github.com/fogleman/sdf) but need do do some experimenting/benchmarking first.

Re: Marble Fountain

#64

Post by cissou »

stavros wrote: post #53
LandStander wrote: post #17

This is a great example of a good use case for 3D printers. The smooth marble run action combined with the interwoven organic forms would be a huge PITA to fabricate with any other method I can think of, even if your just making one.

A good use case for 3D printers is random, small, custom household items that greatly increase my quality of life, much more than it is a unique sculpture.

What printer do you use for that and are you happy about it?

Re: Marble Fountain

#66

Post by ljsprague »

kazinator wrote: post #29

Designers of marble fountains who don't use computing to design the paths run into reliability issues: sometimes balls derailing out of their track. They have to observe the contraption, identify problems (balls getting jammed up or jumping out) and then guess at the root causes and make manual adjustments. That's the thing here: he has it running for hours presumably without any ball jumping out. Most of the tracks…

My naïve guess would be that you can't change the route of the ball without asymmetrical track pressure.

Re: Marble Fountain

#68

Post by rjmill »

kazinator wrote: post #29

Designers of marble fountains who don't use computing to design the paths run into reliability issues: sometimes balls derailing out of their track. They have to observe the contraption, identify problems (balls getting jammed up or jumping out) and then guess at the root causes and make manual adjustments. That's the thing here: he has it running for hours presumably without any ball jumping out. Most of the tracks…

Not to dimish the achievement, but TFA is pretty clear about the limitations of the piece:

> I was able to get it working consistently, although it did lose 2-3 balls an hour and could only run for a few hours without the motor overheating.

IMO that's more impressive to hear than if he hadn't mentioned it at all. (I would have assumed more marbles getting lost.)

Re: Marble Fountain

#69

Post by gaudystead »

cissou wrote: post #64
stavros wrote: post #53

Earlier quoted context omitted.

A good use case for 3D printers is random, small, custom household items that greatly increase my quality of life, much more than it is a unique sculpture.

What printer do you use for that and are you happy about it?

I'm not the person you asked, but depending on what kinds of quality of life improvements you're looking for, your budget, your 3D design abilities, and your tolerance for working on the printer versus printing with it, the answer will vary in terms of what works for you.

If you're casually interested, the Bambu Lab A1 combo will do most things you'd want it to do, fairly reliably, but with a closed ecosystem.

If you want something more robust, go for a Prusa, but be ready for a more hands on experience.

If you want an entirely customized bespoke with a high learning curve, go for a Voron.

Re: Marble Fountain

#70

Post by gaudystead »

WillMorr wrote: post #62
bix6 wrote: post #40

Super cool! I would love to see a white / clear one with LEDs. Rainbow road :)

I've actually done clear prints with LEDs installed. The bottom is much brighter than the top and it just look kinda tacky. I briefly hollowed out the supports and tried running fiber optics but it didn't help much. I'm realizing now that I tried a lot of weird shit during this project that just did not work at all or make it into the final product, I should do another video just of all my failed abomination marble r…

Please do! Also just some footage of the machine running from specific angles for a few minutes would be lovely! Nice work! :)
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