Question about mounting an Ilex Acme Synchro #3 shutter

[David Karp]

Hi everyone,

Happy Thanksgiving to all!

I have a question about mounting a 215mm f/4.8 Ilex Caltar Series S lens on a Technika-type lensboard.

Rick Denney gave a great description of the process for mounting a flange on the board in this thread: http://www.largeformatphotography.info/forum/showthread.php?91275-Ilex-4-and-Technika-lens-board.

I think I can handle that.

My question is about the lensboard hole size. I have seen at least one thread online that said 52mm. KEH says 51mm. The SK Grimes website says just under 50.5mm (after converting from the English system (http://www.skgrimes.com/library/used-obsolete-discontinued-shutters/ilex).

All of my lenses are on a Copal or Seiko shutter. Never having mounted a lens on a flange, do these size differences make a difference? Should I have a lensboard opened to 52mm to be safe, or am I risking a light leak?

My cameras are a Walker Titan SF and an ARCA Swiss Discovery with a an adapter board for Technika-type boards. My plan is to have the lens centered in the board, unless someone indicates a reason not to do that with this shutter on a Technika-type board.

I don't have the lens yet. It should arrive soon. Perhaps I should relax and wait until it arrives and then take some measurements? How much in excess should the hole be over the size of the rear element?

A little guidance is appreciated. Thanks!

[wombat2go]

David,
I recommend you wait until you can measure it.

The Ilex #3 here is of partially of metric dimensions; the front and rear element female threads are 45 mm by 0.5 mm pitch.
So I used the metric gearing on the lathe to make the adaptor threads for the new application.

The "spigot" ( using the Australian term) on the rear of the shutter, that would fit into the lens board, is not threaded. It has outside diameter of 48.50mm.
So a clearance hole might be in range 48.60 to 48.75mm

The way this shutter was originally mounted, and the way I am using it in a new camera, is with the rear element being screwed into the shutter to clamp it to the lens board.
So the axial length of the "spigot" and thickness of the lens board is critical too.
I machined a spacer to take up the difference.

The shutter here uses a cable release thread of the old USA parallel standard, not the tapered metric type.
This shutter is suffering from corrosion I think associated with inclusions in the aluminum body casting, so there are voids opening up in the female element threads and I call it fragile.

Having said all the above, I suspect Ilex#3 may have had various dimensions, the above may be not relevant to yours, so please measure yours before doing any modifications.

[David Karp]

Thanks for the information.

[David Karp]

Okay, I received the lens today. The shutter seems to be in good shape. My Gepe cable release fits in it just fine. The shutter came with the flange. It looks like 52mm is just the right size for the lensboard opening.

I have a few questions.

First, the flange does not easily screw onto the shutter. Would it make sense to put some dry silicone lubricant on the threads? I don't want the lens to easily unscrew from the flange, but it seems like I am forcing it if I try to get it to screw all the way down.

The flange has a rounded raised area on the edge of the hole in its center, and a lip protrudes out the other side of the flange. I assume that the raised edge faces outward, and the lip goes into the hole in the lensboard. So, the lensboard hole need only be large enough for the lip to fit into the hole, right?

Finally, is there any reason you could not mount one of these shutters using a retaining ring, just like with a Copal shutter?

Thanks!

[David Karp]

Or, if the flange screwed down all the way is it possible to use the flange as a retaining ring?

[John Kasaian]

Shutters I've had that came with flanges would have issues with the shutter controls binding on the lens board if I used the flange as an inside retaining ring and screwed the shutter up against the lens. board. Maybe that's why they originally came with flanges? I don't know if that is true for all flange lenses, but it has been my experience. YMMV.

[David Karp]

That makes sense. Thanks John.

[Dan Fromm]

David, I have a #3 Acme in front of me. There's a step at the base of the rear tube. If the shutter is attached to a board with a retaining ring (or with the flange used as one) the step will contact the board. I just put a straightedge on the step. It just clears the aperture control lever. This is the only control that enters the rear of the shutter.

Do the straightedge exercise. If you're worried about the aperture control lever binding between the back of the shutter and the board, cut a couple of paper shims to go between the "step" and the board.

[wombat2go]

Yes, on the #3 here, while it is not threaded, there is a shoulder that will contact the board, leaving the aperture arm free to rotate.

[mdarnton]

You can use the flange as a retaining ring. On a thick board use the longer tube side reaching down into the hole since the other way won't give enough threads holding the lens on. On a thin metal board the lump side of the flange goes into the hole and for this the hole will need to be larger, the diameter of the outside of the lump. If you use the tube side on a metal board the threads will bottom out before you have the lens tight. In any case you don't want the fragile threads to touch the sides of the hole, especially on a metal board!

Used as a flange, the tube side goes into the hole and the lens sits on the donut-shaped lumpular side.

(For those who can't visualize this: the Ilex flange is punched out of a flat sheet of brass, not machined, so it goes through some strange and clever tricks to make it work. If I weren't on my phone I'd make a drawing of the unusual cross section of it.)

[David Karp]

Thanks guys. I'll give it a try when I have the lensboard.

[David Karp]

Thanks to everyone who pitched in an answer here.

I finally got around to mounting the flange and putting the lens on the board. Rick Denney's how-to description is right on.

I had the seller cut a 52mm centered hole in a Technika type board. It was just the right size for the flange that came with the 215mm Ilex Caltar.

I marked the flange location on the lensboard so that the lens would be in the proper orientation when screwed in - thanks to Michael Graves' suggestion in the thread I linked above. I went to a local supplier, Allen Bolt in Burbank, who set me up with some 2-56 countersunk screws, the appropriate drill bit and a tapper. The screws require a tiny Allen wrench, which Allen Bolt also supplied. I used my late father-in-law's drill press to precisely drill the holes and made a makeshift handle out of some scrap wood to use with the tapper. The tapper worked smoothly. WD 40 lubricated these operations. After a quick cleanup, I was relieved to see that the holes were in the correct locations and the screws went right in. I now have a nice shorter focal length for my WP setup, and when I remove the front element, it converts to a 14 inch to play with to do some WP portraits.

My blue loctite went missing, but I could not wait to put everything together. Do any of you who mount flanges on metal boards use blue loctite as insurance against the threads loosening?

[David Karp]

I should also say that despite the fact that mounting a Copal or Seiko shutter is much easier, I had some fun working on this project.

[Tin Can]

Please! No Loctite! Just snug is best.

[BrianShaw]

I'm glad to hear that you were successful and had fun. Last time I had to mount something very much like yours I paid $35 and had a camera repairman do it (machine a metal lens board and mount an Acme) overnight. Less fun for me, I suppose, but quite effective.

[David Lindquist]

Thanks to everyone who pitched in an answer here.

I finally got around to mounting the flange and putting the lens on the board. Rick Denney's how-to description is right on.

I had the seller cut a 52mm centered hole in a Technika type board. It was just the right size for the flange that came with the 215mm Ilex Caltar.

I marked the flange location on the lensboard so that the lens would be in the proper orientation when screwed in - thanks to Michael Graves' suggestion in the thread I linked above. I went to a local supplier, Allen Bolt in Burbank, who set me up with some 2-56 countersunk screws, the appropriate drill bit and a tapper. The screws require a tiny Allen wrench, which Allen Bolt also supplied. I used my late father-in-law's drill press to precisely drill the holes and made a makeshift handle out of some scrap wood to use with the tapper. The tapper worked smoothly. WD 40 lubricated these operations. After a quick cleanup, I was relieved to see that the holes were in the correct locations and the screws went right in. I now have a nice shorter focal length for my WP setup, and when I remove the front element, it converts to a 14 inch to play with to do some WP portraits.

My blue loctite went missing, but I could not wait to put everything together. Do any of you who mount flanges on metal boards use blue loctite as insurance against the threads loosening?

Very nice work, Dave. I particularly admire your improvising a tap wrench from scrap wood. I would have felt a compelling need to buy a Starrett no. 93A (well I already have one). Allen Bolt sounds like a great resource and flat head socket head screws lend a certain je ne sais quoi to mounting the lens flange, even though they'll be hidden by the lens and shutter. I agree, Loctite would be overkill.
David

[David Karp]

. . . I would have felt a compelling need to buy a Starrett no. 93A . . . .

That is so true. I want one too. I was going to pick up an inexpensive tap wrench, but I forgot. Once I was in the garage at my in-laws' house, I had to improvise. Probably worked just as well as a cheap one and maybe a touch more satisfying to boot!

[David Karp]

I took a few photos, but I did not have enough hands to make a photo and show me tapping the holes. :-) If I ever get them out of the camera, I'll post a few.

Thanks also to Randy and David on the advice regarding Loctite. I'll skip it.

Brian: Who do you use for repair work and machining? Are they out here in LA? Did they machine a board from scratch? Or did they mill it out and drill/tape the screw holes? Thanks.

[BrianShaw]

...
Brian: Who do you use for repair work and machining? Are they out here in LA? Did they machine a board from scratch? Or did they mill it out and drill/tape the screw holes? Thanks.

Steve Choi, Steve's Camera Repair in Culver City.

For me they started with a Cambo board with a Copal 1 (I think) hole. Originally the lens was mounted to a wooden Deardorf board. The hole was machined to proper size and the lens was mounted with the flange on the back side as a retaining ring. At first I was a bit taken aback since the flange is not blackened, but so far I've seen no reflections from the flange.

[David Karp]

Interesting. Thanks for the tip.

I tried to mount mine using the flange as a retaining ring. The threaded "tube" portion of the flange (for lack of a better description) was too long. It prevented the rear cell from screwing all the way into the shutter.

[David Karp]

Finally, enough free time to post some photos. I thought these might be helpful to someone mounting a flange to a metal lensboard in the future.

The lensboard came from ecbuyonline2008 on Ebay. (Is that Rudy?) He sells nice Shen Hao branded Technika-type boards. One option is for a custom hole size. (http://www.ebay.com/itm/Custom-Drill-Hole-Lens-Board-For-Linhof-Wista-Ebony-Shen-Hao-Chamonix-/271521210979?pt=US_Lens_Boards&hash=item3f37ece263) The board came and the hole was perfectly machined out. I have 1-2 boards purchased from him, and they have been very nice.

The first shot is the lensboard taped securely to a piece of scrap plywood and secured in place with C clamps. I had previously marked the hole locations with a pencil. you can see the pencil marks in the photo. I also used an awl as a starter to help precisely locate the drill bit. The drill press allowed me to make vertical holes. It would be possible to use a good drill or Dremel tool to make these holes, but it is harder to do that perfectly vertically. Having access to my late father-in-law's drill press really helped. WD 40 does a good job of lubricating the cutting process.

[David Karp]

Once the holes were drilled, I pulled the lensboard off of the plywood. It was time to tap the screw holes. This photo shows the lensboard with the four new holes and the high tech tap wrench I created with scrap wood. As Rick Denney mentioned, you screw in a bit, back out a bit, screw in, back out, etc., until you are all the way through. Be careful to try to keep the tapper vertical as you screw down into the holes. If I was going to do this more often, I would probably look to pick up a tapping fixture like this one: http://seasuntools.en.alibaba.com/product/448978226-212451935/Tapping_Fixture.html

It would make it easier to do the vertical holes.

[David Karp]

The first photo shows the flange mounted to the lensboard.

The second photo shows my new-to-me lens mounted on my Improved Seneca Whole Plate camera via my hack job homemade Technika to Seneca adapter.

[Tin Can]

Once the holes were drilled, I pulled the lensboard off of the plywood. It was time to tap the screw holes. This photo shows the lensboard with the four new holes and the high tech tapp wrench I created with scrap wood. As Rick Denney mentioned, you screw in a bit, back out a bit, screw in, back out, etc., until you are all the way through. Be careful to try to keep the tapper vertical as you screw down into the holes. If I was going to do this more often, I would probably look to pick up a tapping fixture like this one: http://seasuntools.en.alibaba.com/product/448978226-212451935/Tapping_Fixture.html

It would make it easier to do the vertical holes.

Beauty! ! do many in a similar way with a hand held 1/2" drill motor and holes saws up to 6".

Clamping and centering are extremely important.

[David Karp]

Thanks Randy. You are right. It would be very easy to mess things up if the board is not held tight. Also, You have to be right on when you drill, or the screw holes will be off.