Data for Ilex #5 pitch thread says x30 tpi. Does someone knows how much is it in metric, (eg. Copal #3 is 58mm x0,75)? Or how much threads per inch?
Data for Ilex #5 pitch thread says x30 tpi. Does someone knows how much is it in metric, (eg. Copal #3 is 58mm x0,75)? Or how much threads per inch?
There are 25.4 millimeters in an inch. This will of course give you a non-standard metric pitch of .846> mm.
"tpi" means threads per inch.
One man's Mede is another man's Persian.
According to this page:
76,2 x 30 TPI
Divide 30 tip with 25.4 and you get t/mm. That would be 1.18 t/mm.
Far as I know there is usually no direct useful metric thread that fits an American thread standard.
It's 3" by 30 tpi.Originally Posted by domaz
One man's Mede is another man's Persian.
To help clarify gth's post. there is no direct replacement. While the sizes may come close, standard and metric sizes are different.
TPI = threads per inch
This is the correct answer.
30 TPI means the screw rotates 30 times to move one inch. Ergo, one turn equals 1/30th of an inch, or 0.03333". Metric pitch is the distance the screw moves in one rotation, so 30TPI = 0.03333" x 25.4 = M0.846 (rounded).
Renes: The pitch doesn't have to be exact, in order to hold things together. Have your machinist turn a test piece at M0.9 (a standard thread), but with only a few threads and see if the parts bind. Having many turns will eventually lead to binding, but fewer turns will just seem stiff.
Charley
If you cut say six threads and make the fit a wee bit loose, it'll work out just fine.
The error should be negligible over five or six threads. I've done this making flanges for a couple pre WW1 Compounds, you can get a very nice fit.
One man's Mede is another man's Persian.
SK grimes has rings for $60 for the Ilex 5 in stock.
www.skgrimes.com
Thanks to all for help.
According to this well known page (on the bottom) thread diameter for Ilex #5 is 75mm
http://www.lensn2shutter.com/shutters.html
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