Cable release thread

[Bob Salomon]

You realize that in the 70 years since this standard was written cable release sockets may have changed?

[Tin Can]

Maybe Bob, but I seem to be able to use most cables with most shutters

and many of us have pre 1950 shutters

[David Lindquist]

Attachment 205692
Here it is again, rescanned from my copy of the original source.

Similar dimensioned drawings can be found in "Screw-Thread Standards for Federal Services 1957 Part III" available here: https://nvlpubs.nist.gov/nistpubs/Le...upp1957pt3.pdf
See page 45. This is described as "...with straight (American) thread"

You'll also see the "taper (European) thread" Its metric dimensions have been converted to inches, in particular its screw thread pitch is given as 50 threads per inch instead of 0.5 mm.
David

[David Lindquist]

And furthermore as a practical matter I have a cable release that I think is of the "American" pattern. It looks like a straight thread; length of thread is about as shown above. Using a leaf type thread gage, its pitch is 44 threads per inch (metric thread gage, pitch 0.5 mm is not a good fit). Wish I remembered where this came from, it looks pretty new. It will screw in to the shutter on my very late 210 mm Apo-Sironar-S rather better than I would have expected, certainly well enough to trip the shutter.

For the sake of completeness a Linhof brand cable release (taper tip, 0.5 mm pitch of course) will screw in to the No. 3 Ilex Acme shutter for my 1964 8 1/2 inch Commercial Ektar and will trip it.
David

[JimboWalker]

Thanks for this crazy amount of info! I still have not received my taps yet. I will run test with a piece of aluminum first and let you know results.

[Tin Can]

Small and big taps break easily

Test on steel or whatever you are tapping

I have several sets of broken tap removers that are also broken

I have sent work to guys like this Broken Tap Removal by Metal Disintegration Machine (MDM)

[RichSBV]

Sorry, I didn't want to upload a huge scan. I did test and it works fine if you download the image and view with an image editor/viewer or it prints out full page size just fine. Next time I'll just do a huge scan... And it's been uploaded as a larger scan already so...

The straight specs are actually pretty worthless as the only thing that matters is the 5-44 tap size...

Cannot read the specs on my 24" monitor

Would you please post them in text

Thank you

[RichSBV]

Very interesting book with lots of good info. Thanks for that link!

Similar dimensioned drawings can be found in "Screw-Thread Standards for Federal Services 1957 Part III" available here: https://nvlpubs.nist.gov/nistpubs/Le...upp1957pt3.pdf
See page 45. This is described as "...with straight (American) thread"

You'll also see the "taper (European) thread" Its metric dimensions have been converted to inches, in particular its screw thread pitch is given as 50 threads per inch instead of 0.5 mm.
David

[David Lindquist]

Very interesting book with lots of good info. Thanks for that link!

You are very welcome. I came across a related document dated 1985 "FED-STD-H28_18A" dealing only with photographic equipment related screw threads and not so detailed as this older version. It did say that it no longer contained a description of the straight ("American") shutter release thread as that standard had been withdrawn 3 Mar 1976.

It does describe the tapered thread version, the "European" one. But now this is described in metric units including the pitch being 0.5 mm as opposed to 50 threads per inch in the 1957 document.
David

[RichSBV]

Thanks yet again! I searched and found that document and the version 'C'. I then searched for the 'ANSI PH3.107' document it references but could not find a free copy... Ah-well, not worth $25 for me

You are very welcome. I came across a related document dated 1985 "FED-STD-H28_18A" dealing only with photographic equipment related screw threads and not so detailed as this older version. It did say that it no longer contained a description of the straight ("American") shutter release thread as that standard had been withdrawn 3 Mar 1976.

It does describe the tapered thread version, the "European" one. But now this is described in metric units including the pitch being 0.5 mm as opposed to 50 threads per inch in the 1957 document.
David