Re: Home made Lenses ( was Large Format Lens Question. Low tech answer)

John Cremati Wrote:

......... I used to have a old lens making machine that
> was simply a lens mold rotating on a centered arbor.... You would put the
> glass by doping with hard wax on a arbor and then put this in contact with
> the mold..........They still make these machines... Salem Distributing sells
> the various grits, polishes, exc..... http://www.salemdist.com/
>

One could use a drill press in place of a specialized lense grinding machine
.My Dad used to make specialty lenses for research projects at the U. of
Chicago by mounting the glass blank on a shaft that would fit in a drill
press. I don't know the details of what they used to grind the glass against
but the two surfaces sat in a tub of water and abrasive slurry. The drill
press was run with a weight hanging on the operating arm. The operation
could take days and was very hard on the drills bearings (not used to
continuous turning under load). He often referred to the drill press they
only used for non-precision work as the one with worn bearings from grinding
lenses. A more modern machine with even cheap ball bearings would probably
handle the job with ease.

Jack
Received on Sun Feb 27 13:50:26 2005