ATM 2 inch filter threads - pitch?

[Greg Granville <greg@laser.arl.psu.edu>]

I'm making a crayford focuser and I'd like to thread the bottom of the draw tube
to accept standard 2 inch filters. My lathe is capable of cutting metric
threads, but I don't have a metric thread-gage. (they appear to me metric - or
an oddball SAE thread)

Anyone know what the thread pitch is?

Thanks
-- 
Greg Granville
greg@penn.com - greg@laser.arl.psu.edu
Visit the Central Pennsylvania Observers at:
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