
How to design parabolic, hyperbolic, elliptical reflectors for 3D printing - krisraghavan
http://stratnel.com/2016/07/28/how-to-design-parabolic-reflectors-for-3d-printing/
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sgnelson
This is a nice tutorial, but it seems a bit kludgey (and I'm guessing part of
that is due to Fusion 360's "not quite a fully finished CAD system," though
they are making pretty good progress with it, and I find it's a fairly nice
program, especially for the price, (free to hobbyists) and it includes CAM
abilities.)

I would think OpenSCAD would be pretty decent at this, but honestly, I've
never tried making parabola's or similar with it.

A quick google found this openscad script for parabolas:
[http://www.thingiverse.com/thing:84564](http://www.thingiverse.com/thing:84564)

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chris_va
If you had a specific design in mind, it might actually be more satisfying to
generate the STL triangles directly. You can fit your parabola in 2D (by, say,
computing reflection angle to a fixed focal point), then just rotate and dump
out STL.

The wiki has a nice intro to the subject:

[https://en.wikipedia.org/wiki/Parabolic_reflector](https://en.wikipedia.org/wiki/Parabolic_reflector)

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pauw
Alternatively, one could use the "define curve by equations" feature. Most CAD
tools have it.

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duke360
ok for the 3d printing of the "structure" but then how to make it reflective?
do you use regular allumination chamber or what technique ? which precision
you can achieve to validate the prototype ?

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lutorm
Obviously it's for a metal 3d printer...

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sgnelson
Most metal 3d printers simply don't have the surface finish to make this
feasible, never mind cost (it'd be ridiculous).

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lutorm
I guess i should have added a ;-).

Although the laser sintering printer downstairs produces quite nice surface
finishes. Not good enough for an optical mirror, but definitely good enough
for mm-wave antennas.

