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renes
19-Oct-2011, 06:17
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?

E. von Hoegh
19-Oct-2011, 06:44
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.

domaz
19-Oct-2011, 06:46
According to this page (http://www.suaudeau.eu/memo/pratique/Les_obturateurs_centraux.html):
76,2 x 30 TPI

gth
19-Oct-2011, 06:47
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.

E. von Hoegh
19-Oct-2011, 06:50
According to this page (http://www.suaudeau.eu/memo/pratique/Les_obturateurs_centraux.html):
76,2 x 30 TPI

It's 3" by 30 tpi.

cdholden
19-Oct-2011, 07:03
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

c.d.ewen
19-Oct-2011, 08:11
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.

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

E. von Hoegh
19-Oct-2011, 08:22
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.

Robert Hall
19-Oct-2011, 08:55
SK grimes has rings for $60 for the Ilex 5 in stock.

www.skgrimes.com

renes
19-Oct-2011, 09:14
Thanks to all for help.


It's 3" by 30 tpi.

According to this well known page (on the bottom) thread diameter for Ilex #5 is 75mm

http://www.lensn2shutter.com/shutters.html

?

E. von Hoegh
19-Oct-2011, 09:21
I don't know, as I do not have one to measure, but 75mm is probably the inside diameter of the female thread. 76.2 mm could be the outside diameter of the male thread, and is precisely 3". These numbers make sense to me as far as thread dimensions go.

If you have a machinist who knows how to cut threads, don't worry, he'll do it right.

I stated that it was 3" x 30 tpi because it makes no sense to specify the diameter in millimeters and the thread pitch in inches.

c.d.ewen
19-Oct-2011, 09:37
Renes:

I was just finishing an Ilex 5 adapter this morning. I usually rough the male side to 2.995" (76.07mm), then cut the threads about 0.025" (0.64mm) deep. Do you have an Ilex 5 to give to your machinist? As E. von Hoegh says, he'll know what to do.

Charley

Fotoguy20d
19-Oct-2011, 12:56
There's a Chinese seller on ebay who has flanges for the #5 for under $25 US. I just got one in the mail today (took about 2 weeks to receive) - it fit my #5 just fine.

Dan

E. von Hoegh
19-Oct-2011, 13:13
He's talking about the threads for the lens cells.

renes
19-Oct-2011, 13:25
I don't know, as I do not have one to measure, but 75mm is probably the inside diameter of the female thread. 76.2 mm could be the outside diameter of the male thread, and is precisely 3". These numbers make sense to me as far as thread dimensions go.

If you have a machinist who knows how to cut threads, don't worry, he'll do it right.

I stated that it was 3" x 30 tpi because it makes no sense to specify the diameter in millimeters and the thread pitch in inches.



Renes:

I was just finishing an Ilex 5 adapter this morning. I usually rough the male side to 2.995" (76.07mm), then cut the threads about 0.025" (0.64mm) deep. Do you have an Ilex 5 to give to your machinist? As E. von Hoegh says, he'll know what to do.

Charley

I hoped my mechanist is able to make an adapter for Ilex #5 without having it in his hands, but he need it, otherwise it's too risky that somenthing will not work.

Thanks again for your advice.

E. von Hoegh
19-Oct-2011, 13:40
Yes, your machinist will need to cut the thread to fit - by feel - the shutter. Even if he had a lathe to cut inch/American standard threads, it would be best if he had the shutter. With a metric lathe, all bets are off. He'll need the shutter.

Best of luck.

c.d.ewen
19-Oct-2011, 14:01
Renes:

Your machinist can make the adapter from a sketch and some dimensions; he's just being very cautious because of too many unknowns.

I regularly fit my lenses to shutters, and have made couplers to hold them when they aren't mounted in the shutters (more lenses than shutters!). Pictured below are the front and rear cells from a 16 1/2" Dagor :D set in brass adapters that allow them to be used in an Ilex 5. The adapters are screwed into an aluminum barrel, which has the same dimensions and threads as an Ilex 5. I'll happily loan you the coupler, so your machinist has something to work with, if you'll pay the postage.

Charley

Fotoguy20d
19-Oct-2011, 14:08
He's talking about the threads for the lens cells.

Sorry. Too excited about being able to finally put my 14" CE on a board to have read carefully.

Dan

Jim Jones
19-Oct-2011, 14:45
The plot thickens. A National Camera Repair Handbook gives the Ilex No. 5 Universal shutter mounting threads as 82mm (3.228") x 30 TPI and the inside threads as 75.3mm (2.965") x 40 TPI. It seems illogical for anyone to specify metric diameters and TPI in inches, but it worked for Leica.

Jim Galli
19-Oct-2011, 15:07
Modern lathes skip 30 TPI going from 28 to 32. Isn't 30 TPI a leftover from British Whitworth measurements? And were they cut at 55° instead of 60. Which makes one wonder if Ilex started making things with a civil war era lathe and then just stuck with an obsolete standard. So many questions...........and everybody that knew is dead.

John Jarosz
19-Oct-2011, 15:22
Ilex table from SK Grimes site (http://www.skgrimes.com/library/used-obsolete-discontinued-shutters/ilex)

I've cut threads for cells to mate with an Ilex #5 shutter based on numbers shown in the above table. They are correct.

David Lindquist
19-Oct-2011, 17:00
Modern lathes skip 30 TPI going from 28 to 32. Isn't 30 TPI a leftover from British Whitworth measurements? And were they cut at 55° instead of 60. Which makes one wonder if Ilex started making things with a civil war era lathe and then just stuck with an obsolete standard. So many questions...........and everybody that knew is dead.

Yes, this was generally the case with American built lathes, with four exceptions: At the low end the 12 inch Atlas/Craftsman included 30 TPI in its quick change gear box, in the middle the South Bend "Heavy 10" 10 inch lathe with the "wide range" quick change gear box (which was standard the last several years this machine was in production) also included 30 TPI among the threads it would cut. And at the high end of American tool room lathes both the Hardinge HLV-H and the Monarch 10EE would cut 30 TPI. There were probably others in the past. Neither the Atlas Craftsman nor the South Bend ""Heavy 10" are made any more. Only Hardinge Brothers or Monarch Lathes could tell you for sure whether or not they would build you one of their lathes, and how much it would cost.
David

E. von Hoegh
20-Oct-2011, 06:42
Once again, the problem here is that the threads will be cut on a lathe that cuts metric threads only. .9mm is the closest standard metric thread, so the machinist will have to cut only a few threads, and then deepen them until the parts mate closely enough to preserve some semblance of centering without binding.

Whitworth threads are indeed 55 degrees, but this affects the cutting tool only.

renes
20-Oct-2011, 08:44
Renes:

Your machinist can make the adapter from a sketch and some dimensions; he's just being very cautious because of too many unknowns.

I regularly fit my lenses to shutters, and have made couplers to hold them when they aren't mounted in the shutters (more lenses than shutters!). Pictured below are the front and rear cells from a 16 1/2" Dagor :D set in brass adapters that allow them to be used in an Ilex 5. The adapters are screwed into an aluminum barrel, which has the same dimensions and threads as an Ilex 5. I'll happily loan you the coupler, so your machinist has something to work with, if you'll pay the postage.

Charley

Thanks Charley for your offer, much appreciated. I think I should have soon Ilex #5 shutter, if not than I will borrow your coupler.

c.d.ewen
20-Oct-2011, 11:17
Thanks Charley for your offer, much appreciated. I think I should have soon Ilex #5 shutter, if not than I will borrow your coupler.

Sure thing, Renes.

FYI: In case you're unaware, there are different versions of the Ilex 5. The generic one (which is the one we've been talking abouty here) will have Ilex's name on the front plate. Kodak used the Ilex 5 for some of their lenses, and these will have Kodak's name on the front. There's also a much older version with a black face, and just marked " Ilex" & "Universal". These will have different sized cell openings than the generic (Kodak smaller, black face larger).

Charley

norman valentine
23-Oct-2011, 11:27
I had to cut a 40tpi thread on a metric lathe and after consultation on a engineering website it was suggested that I cut the threads at the nearest metric pitch (can't remember what it was) to 3/4 depth and then use a "chaser" of the correct pitch held by hand to finish the thread to size. It was quite hairy as I was using a home made aluminium casting that had had a lot of maching. The first one resulted in an almost perfect fit but the second was tight but still did the job. I'd do it again but it added a few years on me!