Henry Segerman


http://3dprintmath.com - http://www.segerman.org - Mathematician and mathematical artist working in 3 dimensional geometry and topology.

New racks mechanism: Five axis racks http://shpws.me/QGcX Five axis racks
henryseg commented on Grid (stereographic projection) by henryseg
February 14, 2018
Grid (stereographic projection)
henryseg @shiekh Yes, LEDs don’t get near hot enough to cause a problem. Perhaps if the LED were directly in contact with the plastic I might worry.
henryseg @cpabaraboo No - the minimum wall thicknesses are right around the same value for both WSF plastic and the cast metals. Particularly up at the top, the design is right up against those limits.
henryseg @cpabaraboo I just set it available in brass and bronze. I haven't tried it in these materials, but I think it should work well, since they are cast from a wax print. The stainless steel materials I think would be subject to too much distortion in the intermediate steps to work well.
henryseg @swishgirl the issue is that standard lightbulbs are big - the effect only works well with a very small light source. Everything would be very fuzzy with an ordinary lightbulb.
henryseg @Oscelot The positioning of the light is very important to get the right effect - I think it would be very difficult to get it consistently right if it was held in with rubber bands.
henryseg @Oscelot I've thought about this, but the issue is that I don't know what kind of mount to build. If there were a specific LED light design then I could design for it...
henryseg commented on Honeycomb (stereographic projection) by henryseg
December 22, 2017
Honeycomb (stereographic projection)
henryseg @natevplas Good luck!
henryseg @natevplas Ah, I think your software is doing some sort of normal projection onto the surface, and so that pulls the design radially inwards towards the center of the sphere. So putting the light at the center gives back the right design. I use Rhinoceros, but I don't use a "wrap onto surface" command. Rather, I take the curves of the design and extrude them to a point - the north pole of the sphere. Then cut holes in the sphere according to the extrusion.
henryseg @natevplas Is your light in the center of the sphere in that image? In stereographic projection you want the light at the top of the sphere.
henryseg @natevplas If you’d be ok with the square grid, it’s up on thingiverse at https://www.thingiverse.com/thing:202774 (non commercial license). Or do you specifically want the hex grid?
henryseg @natevplas Are you thinking of printing something as a one-off for use with your particular wall fixture, or are you thinking of making multiple copies of a wired up light? What kind of light source do you have in mind? LED? Something else?
henryseg @joachim0 You'll want a very small LED with as wide a spread of angles as possible. I know these things exist, although I've never wired up one myself. Also you want to position the LED in the right position. I imagine this could be done with wires. If I were going to make it as a permanent fixture I would design the 3D print to include a mount that the LED can be attached to, although of course I can't do that without knowing what kind of LED to use.
Improved version of tetrahedral racks: http://shpws.me/OL7a Tetrahedral Racks
henryseg favorited Truncated {4,3,6} by roice3
March 8, 2017
A diamond earring and a diamond earring. http://shpws.me/O9qP Diamond earrings
henryseg commented on Triple gear by henryseg
February 17, 2017
Triple gear
henryseg @fb81847 Hi, service@shapeways.com are the people to ask about shipping questions :)
henryseg @Strawman Wow, awesome mod!
henryseg @Painmedicine1 I looked into this, for Shapeways' pilot project for interlinked metal parts. The problem is that the gear teeth come very close to each other, and so I suspect that they would fuse together. If there's a little fusing in plastic it's no problem to snap apart, but with metal you likely wouldn't be able to.
My book "Visualizing Mathematics with 3D Printing" is now available on Amazon! https://www.amazon.com/Visualizing-Mathematics-Printing-Henry-Segerman/dp/142142035X
Trailer video: https://www.youtube.com/watch?v=JIM-IWh_-n0
Book website: http://3dprintmath.com
henryseg commented on Borromean racks by henryseg
June 11, 2016
Borromean racks
henryseg @dumky If you look closely at the render, you'll see that each of the three racks consists of a long part with a separate plug.
For the past 3 years or so, I have been writing a popular mathematics book, "Visualizing Mathematics with 3D Printing". It's an accessible introduction to some very beautiful ideas - symmetry, polyhedra, the fourth dimension, tilings, knots, surfaces and so on. The twist is that most of the figures in the book are photographs of 3D prints, almost all of which I made through Shapeways. This collects together much of my work over the past few years, and explains how they all fit together!

The book is now available for preorder through Amazon:

henryseg commented on Torus Earth by henryseg
June 6, 2016
Torus Earth
henryseg @Mickanator I hadn't thought about doing relief - it could be done (at exaggerated vertical scale), although it's not as obviously natural as just doing the colours. This model came out of this paper: http://arxiv.org/abs/1605.01396 - which is primarily about 2D textures.
henryseg commented on Hyperbolic paraboloid by henryseg
February 16, 2016
Hyperbolic paraboloid
henryseg @Alex_J8y_Feingold Incidentally, you might be interested in this workshop I'm co-organising: https://icerm.brown.edu/topical_workshops/tw16-1-im/
henryseg @Alex_J8y_Feingold Well, I was going to post a Python script, but this comment box destroys the formatting... email me if you're interested!
henryseg @Alex_J8y_Feingold I've always used the Mac version of Rhino, it's had Python working for years. I hear that a Mac version of Grasshopper is currently under development.
henryseg @MaxCooper67 Yeah, it's great to design geometry with code!
henryseg @MaxCooper67 I use Rhinoceros to make my designs, together with its Python scripting interface.
henryseg commented on Hilbert Curve by henryseg
January 4, 2016
Hilbert Curve
henryseg @Gregory3 Huh, I wonder if Shapeways started showing more digits recently. Odd that I would have said 4.4cm if this page says 4.44cm. In any case, the print is so flexible and springy, that a fraction of a millimeter doesn't matter much.
henryseg commented on Figure 8 Knot by henryseg
January 1, 2015
Figure 8 Knot
henryseg @fischfluous There is a secret version of the program that allows export, you can ask the author Jack van Wijk for a link!


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