> Peter, > > The link to the site of Karl Schwarzinger didn't work but this one does. > http://members.aon.at/sundials/index.html > Look for picture 40 (Bild 40) > > The tree of Sonius is made of two separate plates and calculated as you > suggested. > A dial on the north plate and a dial on the south plate with the dial > centers on the same (imaginair) polestyle. > > The slots in the plates were not cut in the direction of the hourplanes. > It was considered but it was to complecated in this case. > Because of the thickness of the two pates the slots needed to be of > different width. > That was the most difficult part of the calculations. > > In an massive block an aesier method for the calculation is to calculate how > the hourplane is oriented for each hourline in respect to the plane of the > dial or to the horizontal plane. > It's the hourline and an angle to the hourplane. > This is enough to rotate the block in the right position to cut the slots in > the block. > > Read in Compendium vol. 6 nr. 3 and 4, 1999, the aticles about Shadow Plane > Sundials. > > On Internet look at the site of De Zonnewijzerkring ( address below) and > follw the links: > - Links > - Members > - Fer de Vries > Somewhere down you find links to the same articles in Compendium. > > Best wishes, Fer. > > > Fer J. de Vries > > De Zonnewijzerkring > mailto:[EMAIL PROTECTED] > http://www.de-zonnewijzerkring.nl > > Home > mailto:[EMAIL PROTECTED] > http://www.iae.nl/users/ferdv/index-fer.htm > Eindhoven, Netherlands > lat. 51:30 N long. 5:30 E > > ----- Original Message ----- > From: "Peter Mayer" <[EMAIL PROTECTED]> > To: <sundial@rrz.uni-koeln.de> > Sent: Friday, November 19, 2004 4:32 AM > Subject: 'Wineglass' of Sonius > > > > Hi, > > > > I've been thinking for some time about making dial on the model of > > the "Tree of Sonius" in Limburg, Belgium (see Karl Schwarzinger's great > > homepage: http://members.tirol.com/k.schwarzinger/b_5650.htm for a > > picture of the dial and a very clear diagram illustrating the principle > > of the dial. Thanks Karl!). Since my model will be for the southern > > hemisphere, but is to be read 'left to right' it will have to be > > 'bowl-shaped' (or as I prefer to think of it, 'wineglass-shaped'!) > > rather than 'umbrella-shaped' as is the Limburg original. > > My question to the group is: what is the simplest, most sensible way > > with a modest kit of hand/power tools to cut the complex shadow plane > > slots for each hour? > > My present thinking suggests i) drawing a normal vertical dial for > > my location on the north face, then ii)'extending' the angle of the > > style (from the 6 o'clock line) across the side of the block which > > constitutes the dial and using the intersection of the style extension > > with the south side of the block to position and draw a second vertical > > dial--a mirror image, of course. Step iii) is to connect the respective > > hour lines on the two faces across the edges. Step iv) would be to > > successively align the block so that each hour plane is vertical and use > > a mitre box to cut the shadow plane slots. > > Since Fer de Vries co-designed the original, I'm sure he'll have a > > far more sensible plan! (How on earth was it done in stainless steel??) > > > > Many thanks, > > > > Peter Mayer > > > > -- > > Peter Mayer > > Politics Department > > Adelaide University, AUSTRALIA 5005 > > Ph : +61 8 8303 5606 > > Fax : +61 8 8303 3446 > > e-mail: [EMAIL PROTECTED] > > > > ----------------------------------------------------------- > > This email message is intended only for the addressee(s) > > and contains information which may be confidential and/or > > copyright. If you are not the intended recipient please > > do not read, save, forward, disclose, or copy the contents > > of this email. If this email has been sent to you in error, > > please notify the sender by reply email and delete this > > email and any copies or links to this email completely and > > immediately from your system. No representation is made > > that this email is free of viruses. Virus scanning is > > recommended and is the responsibility of the recipient. > > > > > > - >
-
