Thread spec

[Ibbo!]

Does anybody know the spec of the 48mm filter threads

is it .5 or .6 or some imperial size

Thanks

Steve

[JamesF]

0.75mm. Allegedly.

James

[JamesF]

See the answer to the question "What are the thread sizes on Lumicon filters?" here:

http://www.lumicon.com/faq.php

James

[Ibbo!]

Thanks for that link

I will try a .75 and try it but my thread gauge says finer but I can't quite see which it is as I can't find my magnifying glass

i could with a microscope as well as a telescope at the moment

[JamesF]

Reading a few other bits I found on google suggests that the cutting of the threads is not that accurate as a rule and they could be anything between 0.6mm and 0.75mm. I'd guess that as the filters rarely go on more than a few turns it's entirely possible that they could not be particularly accurate and still fit enough to be considered "working".

James

[Ibbo!]

Yes I think we have read similar threads(pun intended)

If its cloudy I will spin the lathe up tonight and see what happens

my concern is not to strip or cross the existing thread

[Stu_2011]

Yes I think we have read similar threads(pun intended)

If its cloudy I will spin the lathe up tonight and see what happens

my concern is not to strip or cross the existing thread

I aim for 0.7 mm on my cheap Chinese lathe and it seems to work, a bit loose so I don't do things up to tight but it seems ok.

Thanks

Sent from my iPad using Tapatalk

[JamesF]

my concern is not to strip or cross the existing thread

I'm sure as long as you're sympathetic when you offer up the threads that should't be a problem.

James