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3D printed mirror array

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Re: 3D printed mirror array

#141

Post by intrasight »

serf wrote: post #89
intrasight wrote: post #79

I wonder if rather than "additive" you could do similar with "subtractive" fabrication. Take a wooden board and cnc mill and cut circles on the surface at the appropriate orientations.

yes, but it'd require a redesign or very special tooling. that spacing between each mirror 'pedestal' is fairly deep, it'd require a very long end-mill or a five axis machine to be able to get into those crevices. it'd be trivial to carve the needed angle into each 'mirror pedestal' , but the current design doesn't support the premise very well.. still, doable.

How about this approach. Just have a collection of wooden dowels with one end milled to be concave at one of 20 or 30 angles. Then you can assemble whatever mirror array you want by selecting and positioning the appropriate dowels. Or sold as a kit made out of plastic hex shaped rods that snap together.

Re: 3D printed mirror array

#143

Post by fudged71 »

mrfusion wrote: post #3

I was going to suggest you could use it as a home decoration to make a message everyday but it would only work one day a year?

It's possible to create artificial light with parallel rays like the sun, you just need a parabolic dish mirror. So in theory yes you could do this at home for everyday projections, just not with the sun.

Re: 3D printed mirror array

#145

Post by alok-g »

codazoda wrote: post #67
jacquesm wrote: post #30

What an absolutely amazing piece of work, and even more incredible that it worked the first time. If I had to do something like that it would take me at least three tries to get it to work and quite possibly more than three. Math, 3D printing, love, what's not to like :) And congratulations!

Even simple stuff takes me multiple tries. I don’t know how any engineer gets a design right the first time. I can build it in a 3D design app, look all around it, and STILL see something in the prototype that was not obvious in the design.

I have gotten designs first-time right multiple times in my career, and in fact more often first-time right than not. And so for both hardware and software.

For the last few years however I have gradually been loosing that and have started going easier on myself when I discover a mistake.

The requirement to get it right in the first time is more stringent for integrated circuit designers (which I have been too) as cycle times are in months. It is true that several tools are set up around this to help find issues before designs are sent out for fabrication. However, the tools are not perfect, and considerable insights, eye for detail and perfectionism and are still required to make a design work in the first shot.

Re: 3D printed mirror array

#146

Post by autoexec »

Mountain_Skies wrote: post #66
thih9 wrote: post #61

Earlier quoted context omitted.

> put it on your own roof, that way nobody can remove it I imagine you’d need a permission; just like you’d have to get one if you wanted to use a projector and project something onto parliament. (TINLA)

One of my friends used to live across the street from a federal courthouse. He tried projecting a movie from his window onto a blank wall of the courthouse. Half an hour later several LEOs were at his door asking him "politely but firmly" to turn off the projector and to never do it again.

Was it actually illegal or did they just bully him into doing what they wanted?

Re: 3D printed mirror array

#147

Post by autoexec »

gnramires wrote: post #14
_Microft wrote: post #8

I might be getting old but this is the sort of magic by technology I would like to see more of in the world instead of using tech to try putting people into fake worlds in some metaverse.

I don't think the particular metaverses available right now seem that good, but I don't share the consistent prejudices against virtual reality. Why is real reality any better? You can build awesome stuff in virtual reality as well (in fact, you can build almost anything imaginable, at a much lower cost). Keeping in touch with reality is extremely important (because we are bound by its rules after all), but virtual e…

> virtual reality is delightfully egalitarian

It could be, but I'm willing to bet it'll be primarily used to oppress and control people. The potential for things like VR and AR is great, but the reality is that it will be used against you in ways that couldn't have been possible without it.

Re: 3D printed mirror array

#148

Post by kragen »

jacquesm wrote: post #115
kragen wrote: post #109

Earlier quoted context omitted.

You might need a micron of thickness of aluminum or silver. This piece looks like it's about 300 mm x 300 mm, which would work out to 90 mm³ of silver (or aluminum), which at 10.5 g/cc would work out to 950 mg of silver. Silver currently costs US$25.25 per troy ounce, so this would be 0.12¢ (US$0.0012) of silver, or somewhat less of aluminum. Both silver and aluminum will tarnish if exposed to the air, silver more sl…

I've silvered a lot of copper plates for photography (Daguerrotypes).

Well, as usual, you probably know more than I do about what I'm writing about. Am I overlooking something significant? I don't even know if you can use the Tollens test to silver copper.

Re: 3D printed mirror array

#149

Post by vagrantJin »

arketyp wrote: post #127
berkes wrote: post #121

Earlier quoted context omitted.

A lot of art is about "the process". I mean, the resulting painting as done by Pollock or Mondriaan is pretty silly. Just splash some paint in a canvas, or draw some lines and use the "fill bucket tool" to create colored squares, right?

Yes, sure, it's about the process and about the inescapable context with postmodern conceptual art. Whether it's mere splashes I will leave aside, but Pollock and Mondrian precisely brought the consideration of the process to a new light, that's part of what makes them significant figures. Mondrian didn't have mspaint.exe, those geometries meant something different at the time. Also, I don't think Picasso would have…

> but Pollock and Mondrian precisely brought the consideration of the process to a new light, that's part of what makes them significant figures.

Oh. I thought people saw something I couldnt.

Re: 3D printed mirror array

#150

Post by elliottkember »

berkes wrote: post #121
arketyp wrote: post #114

Earlier quoted context omitted.

No knock on the artist, I particularly like the pom-pom display, but I get the sense that much of art today is about going roundabout ways, almost Rube Goldberg machine like, to achieve things could be presented in other ways with minimal effort. Sometimes this alternative mediation is interesting, but sometimes it almost feels dismissive of the metaphysical magic that is computing.

A lot of art is about "the process". I mean, the resulting painting as done by Pollock or Mondriaan is pretty silly. Just splash some paint in a canvas, or draw some lines and use the "fill bucket tool" to create colored squares, right?

Linguistically, the art is the process, and the result is a “work of art”. One of my favourite misunderstood language quirks.
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