Archived posting to the Leica Users Group, 2002/03/24
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 7:29 AM -0800 3/24/02, Dennis Painter wrote: >How much is a tonne of Leica glass? > >Well 10,000 metric tonne really. > >Which is 10,000,000 kilograms > >Per Schott Glass Product Specification: > >N-LAK34 runs 4.02 g/cm3 or about 4000 kilograms per cubic metre > >(LAK34 is just the first optical glass product sheet I found and this >stuff is really heavy compared to ordinary glass!) > >So 10,000,000 kilograms would be 2,500 cubic metre of glass.or 74,818 >cubic feet. > >That's a pile 10 by 10 by 25, or 10 ft by 10 ft by 748 feet high. That's >a lot of glass, a lot of lens elements. > > >Wasteage in production has been mentioned. It seems unlikely that a >significant number of production melts would be unusable. It is the >nature of manufacturing processes to put in place procedures which will >result in high yields. > >I do believe there is a significant amount of glass "consumed" in the >production of a lens element. Cutting shaping and grinding from a blank >to the final element have to remove material. > >I don't know how much but if only 25% of the material ends up in the >element our pile is still mighty big. > >At this point I wonder if 10,000 metric tons mentioned in Leicaview is >an accurate transcription or translation of the interview with Norbert >Meinert. Perhaps someone knows a way to verify. > >Or maybe I made an error in calculation. ;-) > I assume that your reference to 10,000 tons is regarding Leica's production? If so, I think your decimal had some slippage. I believe the amounts in question were 10 tons/yr, or about 2.5 cubic meters. - -- * Henning J. Wulff /|\ Wulff Photography & Design /###\ mailto:henningw@archiphoto.com |[ ]| http://www.archiphoto.com - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html