24 Sep
2010
24 Sep
'10
3:20 p.m.
> Screw-mount camera lenses. 39mm x 25 tpi. (39mm
x 1mm is a less than
> perfect fit.)
On Fri, 24 Sep 2010, Tony Duell wrote:
I thought Leica thread was 26 tpi, but it's been a
long time since I cut
one... I have no idea if the Russian Leica 'copies' were the same or 1mm
pitch.
Good catch! That would ALSO be a less than perfect fit!
I'm pretty sure that the FED was 1mm pitch, don't know about the Zorki, or
particularly the early East German counterfeit Leicas.
Pentax/Praktica/Edixa thread is certianly 42mm * 1mm
pitch.
But, IIRC, "T-mount" is 42mm x .75mm pitch
And C mount is 32 tpi.
"CS mount" is
the same, but with 5mm difference in registry (distance to
film plane)
Some computer parts have metric fasteners, some don't.
I don't remember, but I would guess that Shugart 8" and full height 5.25"
drives are not metric, but their half-height and 3.5" frives were metric?
--
Grumpy Ol' Fred cisin at xenosoft.com