Hi Art, I saw that you could solve your problem. It would be great if you could post/mail us your solution!
In short mine is the following: I created a pythonscript in blender3d to create the gnomon (either one "medium" or two like Bernhardt or something even more sophisticated) as a 3d model (see my picture at http://commons.wikimedia.org/wiki/File:BernhardtscheWalzen.png). Blender then can export it to many formats which a CNC can probably print (including eg .dxf). Unfortunately I do not have any experience with CNC, but I'd be interested in your results again. I made one with a 3d printer at university, see some prictures at http://picasaweb.google.com/finbref/Sonnenuhren Let me know if you want/need more details, Thomas 2009/3/26 Thomas Steiner <finbref.2...@gmail.com>: > Hi Art, > I am very busy at work, perhaps i can only look at your problem later, > perhaps on the weekend. But as far as I understood, I do have a nice > solution for you. > If you don't hear anything from me within a week, please recontact me. > Thomas > > > > > 2009/3/26 Art Krenzel <phoenix98...@msn.com>: >> Thomas, >> >> I saw your recent posting on the sundials listserve where you discuss >> analemmatic sundials in detail. I joined NASS about a year ago and have >> been reading the sundial list serve during that time. >> >> I have a problem which you might be able to help me solve. I am trying to >> convert a standard equatorial sundial using a simple rod as a gnomon to one >> with a gnomon based on a 3D analemma. This will reduce the amount of >> analemic adjustment from every month to twice a year (to compensate for >> daylight savings time). I have included a photo of a sundial of the type >> which I am seeking to duplicate. >> >> Specifically, I am seeking a program which will plot the shape of the >> analemma on an X Y grid so I can feed the values into a CNC lathe to shape >> the 3D analemma. I want to take the X values and "average" them such that >> the data forms a symmetrical analemma around a central axis. Symmetry of >> the analemma design will introduce small solar compensation errors however 2 >> minutes or so will be acceptable. >> >> To review my goals - I need the two dimensional analemma plotted in XY >> coordinates, not days so I can enter the graphical coordinates into a CNC >> machine. The software on the CNC includes curve smoothing capability so it >> will round the surface produced by the data points nicely. I do use >> DELTACAD. Is there a macro which might do what I need? I have not been >> able to locate one. >> >> I would appreciate your assistance to solve this problem. >> >> Sincerely, >> >> Art Krenzel >> 10505 NE 285th Street >> Battle Ground, WA 98604 >> 360-666-1883 voice >> phoenix98...@msn.com >> >> > --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
