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Dennis Dennis is offline
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Default Wierd threads part 2


"anorton" wrote in message
m...

"Randy333" wrote in message
...
I have a bunch of taps I got at auction. marked .120-102

Any one need some? the thread is like fuzz.

IIRC they were from GE in New York.

Any idea what these were for?

Remove 333 to reply.
Randy


Fine threads like that are often used for adjusters for optical mounts.
Typically they are an even 100 tpi or 80 tpi. 102 tpi is pretty close to
0.25 mm pitch. Sounds like it is for an adjusting screw with a dial
calibrated in millimeters on a device generally designed in inches.


Like these:

http://search.newport.com/?q=*&x2=sku&q2=AJS100-0.5


When I used to do work in that area we bought some taps from Newport or
someone for making these threads.