Re: 3D digital sundial
Bill
I've used OpenScad. It does what it says on the box. But with a steep learning
curve - unless you are familiar with programmical modelling - it's all a matter
of creating a primitive shape, scaling it, rotating it, moving it and then
adding or subtracting from what you have created before. The programming
language is java-like and rather cumbersome. I include a little picture of an
early prototype of the 3D-printered interior shell of a dodecahedral sundial.
(The dial faces will be laser engraved on thin plywood and stuck onto the
shell). Also the OpenScad code to produce this shape.
Give it a try!
Kevin
Height = 100 ;// millimeters
Arm_Thickness= 5 ;
Ply_Thickness= 2.6;
Wall_Thickness_Below_Ply = 3;
Look_Inside = 1; // ENTER 1 TO CUT THE MODEL IN HALF
// *
// D E F I N E T H E D O D E C A H E D R O N A N D P E N T A G O N
// *
module dodecahedron(height) {scale([height,height,height])
{intersection()
{cube([2,2,1], center = true);
intersection_for(i=[0:4])
{rotate([0,0,72*i]) rotate([2 * atan((1 +
sqrt(5))/2.),0,0])cube([2,2,1], center = true);
module pentagon(x_rad,thickn)
{difference() // Carve 3 sides off a Cylinder
{cylinder(r=x_rad,h=thickn+.001);
for ( i = [0 : 4] ) {rotate([0,0,72.*i ]) translate([x_rad,0,0])
cube([x_rad,1.5*x_rad,1.5*x_rad], center = true); }}}
// *
// C A L C U L A T E V A R I O U S P A R A M E T E R S
// *
Gold_Rat= (1 + sqrt(5))/2.; // Golden Ratio
Dihedral= 2 * atan(Gold_Rat); // Dihedral; Angle
Pentagon_Size = Height/Gold_Rat - Arm_Thickness;
Inner_Dimension = Height - 2 * (Ply_Thickness + Wall_Thickness_Below_Ply);
// *
// B U I L D T H E M O D E L
// *
difference() {
// Make Dodecahedron hollow
difference(){dodecahedron(Height); dodecahedron(Inner_Dimension);}
// Remove Pentagons fron Top & Bottom Faces
rotate([0, 0,18]) translate([0,0,Inner_Dimension])
pentagon(Pentagon_Size,Ply_Thickness); // Top Face
rotate([0,180,18]) translate([0,0,Inner_Dimension])
pentagon(Pentagon_Size,Ply_Thickness); // Bottom Face
// Remove Pentagons fron Upper Side Faces
for ( i = [0 : 4] ) {rotate([0,180-Dihedral,90+ i*72 ])
rotate([0,0,36]) translate([0,0,Height/2 - Ply_Thickness])
pentagon(Pentagon_Size,Ply_Thickness);}
// Remove Pentagons fron Lower Side Faces
for ( i = [0 : 4] ) {rotate([0,Dihedral,90+36 + i*72 ])
rotate([0,0,0 ]) translate([0,0,Height/2 - Ply_Thickness])
pentagon(Pentagon_Size,Ply_Thickness);}
// Cut Model in half if desired
if (Look_Inside)
{translate([-Height,-Height,-0]) cube(2*Height);} }
> On 6 Nov 2015, at 14:15, Bill Gottesman <billgottes...@comcast.net> wrote:
>
> Very cool. Has anyone had a chance to try the free 3D software OpenScad? By
> the way, I am skeptical that the sundial can handle declinations near the
> solstices.
> -Bill
>
> On Fri, Nov 6, 2015 at 7:39 AM, Darek Oczki <dhar...@o2.pl
> <mailto:dhar...@o2.pl>> wrote:
> Hello everyone
>
> Have you seen this 3D digital sundial?
> http://3dprint.com/103289/open-source-3d-print-sundial/
> <http://3dprint.com/103289/open-source-3d-print-sundial/>
>
> --
> Best regards
> Darek Oczki
> 52N 21E
> Warsaw, Poland
> GNOMONIKA.pl
> Sundials in Poland
> http://gnomonika.pl <http://gnomonika.pl/>
> ---
> https://lists.uni-koeln.de/mailman/listinfo/sundial
> <https://lists.uni-koeln.de/mailman/listinfo/sundial>
>
>
> ---
> https://lists.uni-koeln.de/mailman/listinfo/sundial
>
---
https://lists.uni-koeln.de/mailman/listinfo/sundial
3D digital sundial
Bill, Kevin I too have been exploring 3D printing for a digital sundial (see http://www.sundials.org/index.php/dial-links/videos/digital-sundials ). Because I do a lot of programming, openSCAD is wonderful, allowing precise control of shapes and allowing structures that until now were only a dream. [Note: for the moment, unless you spend a fortune, you must be content with PLA or ABS plastic ... but through commercial 3D print houses you can get metal as well, but very pricey]. As Bill suspects, the digital dial shown at http://3dprint.com/103289/open-source-3d-print-sundial/ does not work at high sun declinations toward the solstices. I downloaded the model and used Slic3r, MatterControl and CURA as visulaizers (they produce G-code as well) and confirmed that the dial only works to +/- 15 deg solar declination. Sad, because it's a neat design. My original digital dial (1995) showed both hours (8am-4pm) and minutes at 10-minute intervals. Both Scharstein and I received independent patents for essentially the same thing... except that he has been able to commercialize his dial. Mine cost too much to build. At the June 2015 NASS meeting in Vancouver I presented (in abstentia) a video (see URL above) of the principles and construction of a new digital gnomon dial. The design only shows hours, but accurately changes hour with an resolution of 90 seconds. So now I'm taking up the challenge to include minutes, and of course include a way to accommodate the Equation of Time. Willing to collaborate with whoever is interested. This stuff is fun. Bob Kellogg Potomac, MD --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: 3D digital sundial
Very cool. Has anyone had a chance to try the free 3D software OpenScad? By the way, I am skeptical that the sundial can handle declinations near the solstices. -Bill On Fri, Nov 6, 2015 at 7:39 AM, Darek Oczki <dhar...@o2.pl> wrote: > Hello everyone > > Have you seen this 3D digital sundial? > http://3dprint.com/103289/open-source-3d-print-sundial/ > > -- > Best regards > Darek Oczki > 52N 21E > Warsaw, Poland > GNOMONIKA.pl > Sundials in Poland > http://gnomonika.pl > --- > https://lists.uni-koeln.de/mailman/listinfo/sundial > > --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: [SPAM] 3D digital sundial
I've seen :) That's cool. The only disadvantage is relatively low resolution; 20 minutes. Take care, Marek -Original Message- From: Darek Oczki Sent: Friday, November 06, 2015 1:39 PM To: sundial@uni-koeln.de Subject: [SPAM] 3D digital sundial Hello everyone Have you seen this 3D digital sundial? http://3dprint.com/103289/open-source-3d-print-sundial/ -- Best regards Darek Oczki 52N 21E Warsaw, Poland GNOMONIKA.pl Sundials in Poland http://gnomonika.pl --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial
3D digital sundial
Hello everyone Have you seen this 3D digital sundial? http://3dprint.com/103289/open-source-3d-print-sundial/ -- Best regards Darek Oczki 52N 21E Warsaw, Poland GNOMONIKA.pl Sundials in Poland http://gnomonika.pl --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: 3D digital sundial
Oops, no native penguins at north pole as shown in animation. Larry Bohlayer On Fri, Nov 6, 2015 at 7:39 AM, Darek Oczki <dhar...@o2.pl> wrote: > Hello everyone > > Have you seen this 3D digital sundial? > http://3dprint.com/103289/open-source-3d-print-sundial/ > > -- > Best regards > Darek Oczki > 52N 21E > Warsaw, Poland > GNOMONIKA.pl > Sundials in Poland > http://gnomonika.pl > --- > https://lists.uni-koeln.de/mailman/listinfo/sundial > > --- https://lists.uni-koeln.de/mailman/listinfo/sundial
