Re: A Digital Sundial on Instructables
Hi all I think it can also work with a square section, so it should be easy to laser-cut. I also think the holes on the other side of every number may become a window, with inside frames, to allow a projection with any declination of the Sun (a bit more complicated) The problem may be the projection: the ratio between the size of the holes and the distance of the projection may blur it and it could become unreadable. ciao Fabio Fabio Savian fabio.sav...@nonvedolora.it www.nonvedolora.eu Paderno Dugnano, Milano, Italy 45° 34' 10'' N, 9° 10' 9'' E, GMT+1 (DST +2) -Messaggio originale- From: Richard Mallett Sent: Friday, April 24, 2015 10:01 PM To: Robert Kellogg ; sundial@uni-koeln.de Subject: Re: A Digital Sundial on Instructables On 24/04/2015 17:00, Robert Kellogg wrote: Interesting digital dial. I must admit I looked at this design about 20 years ago. The author has one 3D moveable drawing of the completed dial. If you look closely on the underside of the gnomon, there are cut-outs of hour numbers that match the obverse side. Therefore, this sundial works correctly only two days a year (I'm inferring that the numbers were aligned for the equinox). Pity that such a beautiful digital dial is nearly useless. Exactly the same problem with Voshart's digital cube (see http://gizmodo.com/this-digital-sundial-tracks-the-sun-through-a-laser-cut-1545753402). This may force me back to the drawing board since I hold US Patent 5,596,5533 Jan 21 1997 Digital Sundial. (See also Scharstein's US Patent 5,590,093 Dec 31. 1996 Digital Sundial. Dan's patent is earlier, but he had to reference my article in NASS' Compendium). A the modern digital world. I understand that Apple's digital watches are being delivered to those few lucky souls today. --- https://lists.uni-koeln.de/mailman/listinfo/sundial At a time when digital watches are hardly ever seen in the shops. -- -- Richard Mallett Eaton Bray, Dunstable South Beds. UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial
RE: A Digital Sundial on Instructables
The projection distortion could be somewhat compensated by distorting the number cutouts, so the early and late hours are comparatively narrower. Dave -Original Message- From: sundial [mailto:sundial-boun...@uni-koeln.de] On Behalf Of Fabio nonvedolora Sent: Friday, April 24, 2015 1:49 PM To: sundial@uni-koeln.de Subject: Re: A Digital Sundial on Instructables Hi all I think it can also work with a square section, so it should be easy to laser-cut. I also think the holes on the other side of every number may become a window, with inside frames, to allow a projection with any declination of the Sun (a bit more complicated) The problem may be the projection: the ratio between the size of the holes and the distance of the projection may blur it and it could become unreadable. ciao Fabio Fabio Savian fabio.sav...@nonvedolora.it www.nonvedolora.eu Paderno Dugnano, Milano, Italy 45° 34' 10'' N, 9° 10' 9'' E, GMT+1 (DST +2) -Messaggio originale- From: Richard Mallett Sent: Friday, April 24, 2015 10:01 PM To: Robert Kellogg ; sundial@uni-koeln.de Subject: Re: A Digital Sundial on Instructables On 24/04/2015 17:00, Robert Kellogg wrote: Interesting digital dial. I must admit I looked at this design about 20 years ago. The author has one 3D moveable drawing of the completed dial. If you look closely on the underside of the gnomon, there are cut-outs of hour numbers that match the obverse side. Therefore, this sundial works correctly only two days a year (I'm inferring that the numbers were aligned for the equinox). Pity that such a beautiful digital dial is nearly useless. Exactly the same problem with Voshart's digital cube (see http://gizmodo.com/this-digital-sundial-tracks-the-sun-through-a-laser-cut-1 545753402). This may force me back to the drawing board since I hold US Patent 5,596,5533 Jan 21 1997 Digital Sundial. (See also Scharstein's US Patent 5,590,093 Dec 31. 1996 Digital Sundial. Dan's patent is earlier, but he had to reference my article in NASS' Compendium). A the modern digital world. I understand that Apple's digital watches are being delivered to those few lucky souls today. --- https://lists.uni-koeln.de/mailman/listinfo/sundial At a time when digital watches are hardly ever seen in the shops. -- -- Richard Mallett Eaton Bray, Dunstable South Beds. UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: A Digital Sundial on Instructables
On 24/04/2015 17:00, Robert Kellogg wrote: Interesting digital dial. I must admit I looked at this design about 20 years ago. The author has one 3D moveable drawing of the completed dial. If you look closely on the underside of the gnomon, there are cut-outs of hour numbers that match the obverse side. Therefore, this sundial works correctly only two days a year (I'm inferring that the numbers were aligned for the equinox). Pity that such a beautiful digital dial is nearly useless. Exactly the same problem with Voshart's digital cube (see http://gizmodo.com/this-digital-sundial-tracks-the-sun-through-a-laser-cut-1545753402). This may force me back to the drawing board since I hold US Patent 5,596,5533 Jan 21 1997 Digital Sundial. (See also Scharstein's US Patent 5,590,093 Dec 31. 1996 Digital Sundial. Dan's patent is earlier, but he had to reference my article in NASS' Compendium). A the modern digital world. I understand that Apple's digital watches are being delivered to those few lucky souls today. --- https://lists.uni-koeln.de/mailman/listinfo/sundial At a time when digital watches are hardly ever seen in the shops. -- -- Richard Mallett Eaton Bray, Dunstable South Beds. UK --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: A Digital Sundial on Instructables
Great idea. A beautiful form for this type of dial. Thanks for passing on the link. This seems a form that was referred to as punctiform by Gianni Ferrari. His article, Sundials With Punctiform Hour Lines, was in the Compendium for September 2004. It is available on line at http://www.advanceassociates.com/Sundials/Stained_Glass/sundials_files/Ferrari_Gianni_Sundials_with_Punctiform_Hour_Lines.pdf He describes sundials with hour windows much like what is described in this Instructable. It seems this Time-oclock-shadow is a concept simulation using a 3-D drawing program. The author states: Using Autodesk Inventor I first started tracing the angles on a sketch, then I created planes that went through the hour lines and the gnomon line. The hard part is done! Using each plane, extrude the right number out of it. Actually making such a dial would be difficult to extrude numbers. Maybe a laser cutter? As noted by one comment, the numeral form window might suffer some eclipsing from changes in solar declination. That is something he could check in his 3- D program. It would be easier to have a wide window that in turn shines on cut out numerals. It is also notable that the guiding principle the author used was the hourly shadow planes. I used the same idea some years ago in making hour windows filed with vanes of those shadow planes. I never made a permanent model. Just a cardboard model was very time consuming to fill a sizable window with a few dozen vanes. - Claude Hartman 35N 120 W On 4/23/2015 5:24 AM, Richard B. Langley wrote: Came across this, this morning: http://www.instructables.com/id/Time-oclock-shadow/ --Richard Langley - | Richard B. LangleyE-mail: l...@unb.ca | | Geodetic Research Laboratory Web: http://gge.unb.ca/ | | Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142 | | University of New Brunswick Fax: +1 506 453-4943 | | Fredericton, N.B., Canada E3B 5A3| |Fredericton? Where's that? See: http://www.fredericton.ca/ | - --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Re: A Digital Sundial on Instructables
Brilliant. First dial I've seen like that. Thanks for sharing -Bill On Thu, Apr 23, 2015 at 8:24 AM, Richard B. Langley l...@unb.ca wrote: Came across this, this morning: http://www.instructables.com/id/Time-oclock-shadow/ --Richard Langley - | Richard B. LangleyE-mail: l...@unb.ca | | Geodetic Research Laboratory Web: http://gge.unb.ca/ | | Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142 | | University of New Brunswick Fax: +1 506 453-4943 | | Fredericton, N.B., Canada E3B 5A3 | |Fredericton? Where's that? See: http://www.fredericton.ca/ | - --- https://lists.uni-koeln.de/mailman/listinfo/sundial --- https://lists.uni-koeln.de/mailman/listinfo/sundial
