Alternate ways of mounting a lens (ie. no flange or retaining ring)

Discussion in 'Large Format Cameras and Accessories' started by Removed Account, Dec 14, 2007.

  1. Removed Account

    Removed Account Member

    Messages:
    907
    Joined:
    Apr 6, 2007
    Location:
    Nanaimo, Bri
    Shooter:
    35mm
    So I've been hunting for a flange for my Ilex Acme-Synchro #3 and have had little success. I purchased one, which turns out to be for a Kodak Acme-Synchro #3, which for some reason is different from all other Acme-Synchro #3's. Carol at Flutots said she has one, but I think she may be on holidays as I have not yet received purchasing info. If that doesn't work out my only other option is to wait for SK Grimes to make a bunch, which is not unreasonable in cost at $35ish.

    In the meantime I am getting itchy to use my new lens! Searches at work for a filter which fits the rear threads (to scavenge the femal thread ring) have come up nil. Short of using a glue gun, are there any other alternate methods which will suffice until I get my hands on a proper flange?

    - Justin
     
  2. TheFlyingCamera

    TheFlyingCamera Membership Council Council

    Messages:
    9,438
    Joined:
    May 24, 2005
    Location:
    Washington DC
    Shooter:
    Multi Format
    Rubber pipe-clamp will work- not pretty, but it functions... I don't remember what the OD on the Acme #3 shutter is, but it is probably something in the neighborhood of 1 1/2". Go find a pipe clamp that is close to that in size. You may need to cut out a wedge of it, and most likely will have to cut the thing in half (or less) lengthwise. Then just tighten the clamp until the rubber grips the rear barrel of the lens tightly.
     
  3. Dan Dozer

    Dan Dozer Subscriber

    Messages:
    351
    Joined:
    Dec 10, 2004
    Shooter:
    Large Format
    Hi Justin,

    Here is my latest method which is pretty easy and cheap. It does require you to use wooden lens boards rather than metal (you didn't mention what type you have).

    First you cut a hole in the lens board approximately 1/16" larger than the outside diameter of the threads on the lens. I cut one approximately the same size as the threads and then use a dremmel with a small sanding drum to enlarge the hole in the board to the proper size. The sanding drum also smoothes out the edges of the hole very nicely.

    Next, put a piece of double sided scotch tape around the hole on the inside of the hole and trim it to the thickness of the board. Don't worry if it sounds like we going to tape the lens in place, this technique really works.

    Next, get a piece of 1/16" thick black foam from your local crafts shop - I got mine from Michaels for around 1$ for a sheet that is about 12" x 18". Cut a strip of foam the thickness of the lens board and cut it to length to fit inside the hole opening in the board.

    Tape it in place to the double stick tape. This will give you a lens board hole that is lined with foam.

    Next, you simply screw the lens into the foam "gasket" in the hole and it should fit very snugly and tight. It might take some work to get it started going in straight, but once it starts going in, it's pretty easy from there.

    I used this method on a 36 cm. Heliar in a 6 x 6 lens board for my 8 x 10 Kodak 2D (very big and very heavy lens) and it fits very tightly and secure. There is no worry about it falling out, and with the foam, there is not any chance of light leakage.

    With this method, there is no reason why I need to look for a mounting flange for the lens.

    Hope this helps - good luck,

    Dan
     
  4. Removed Account

    Removed Account Member

    Messages:
    907
    Joined:
    Apr 6, 2007
    Location:
    Nanaimo, Bri
    Shooter:
    35mm
    Thanks guys! The home depot and Michael's are in the same area, so I think a trip up there before work tomorrow is in order. I have metal lensboards on my Cambo, but one of my housemates is pretty handy with a dremel so if I offer up some coffee (and replacement bits) he'd be able to get the hole opened quite nicely. You are correct Scott, the diameter is 1.5". Dan, what is that foam normally used for? I'd think it is pretty dense but I'd like to know what to look for. There is a smaller craft shot right by work, so I will take a look there first. Thanks again,

    Justin
     
  5. Phillip P. Dimor

    Phillip P. Dimor Member

    Messages:
    1,063
    Joined:
    Oct 25, 2004
    Location:
    Westport, MA
    Shooter:
    Large Format
    I've used hose clamps, nylon zip ties, duct tape.. I've use these three items to mount everything from an aero ektar and wollensak 15" telephoto to smaller lenses like 7" anastigmats. I like the foam gasket idea on a wood lensboard, that is pretty slick and i've done similar using a plastic diy lensboard and linen tape. If you don't care how it looks and only how it works, there are plenty of ways to stick anything on a board once you think about it.
     
  6. richard ide

    richard ide Member

    Messages:
    1,227
    Joined:
    Nov 8, 2005
    Location:
    Wellington C
    Shooter:
    Multi Format
    Cut a hole in a thin piece of sheet metal just slightly smaller than the maximum thread diameter. cut a slit about 3/8" long and bend one corner very slightly. This will now screw onto the thread well enough that a temporary fix has lasted over 20 years. Another idea would be to cut 3 or 4 small metal tabs and glue or screw them to the lensboard with the edge of the tabs engaging the thread.
     
  7. JBrunner

    JBrunner Moderator Staff Member Moderator

    Messages:
    7,075
    Joined:
    Dec 14, 2005
    Location:
    Basin and Range Province
    Shooter:
    8x10 Format
    Just out of curiosity, how are large diameter threads machined? I've never seen a tap & die set like that, but it would be nice to be able to thread 1 1/2" brass tube for making a home made lens or lens ring, etc.
     
  8. noseoil

    noseoil Member

    Messages:
    2,898
    Joined:
    Oct 6, 2003
    Location:
    Tucson
    Shooter:
    Multi Format
    A thick automotive "o" ring may work as well (3/16"). If it is a snug fit, you can roll or thread it onto the lens like a nut. tim
     
  9. Ole

    Ole Moderator Staff Member Moderator

    Messages:
    9,281
    Joined:
    Sep 9, 2002
    Location:
    Bergen, Norw
    Shooter:
    Large Format
    with special tools, on a lathe. :smile:
     
  10. richard ide

    richard ide Member

    Messages:
    1,227
    Joined:
    Nov 8, 2005
    Location:
    Wellington C
    Shooter:
    Multi Format
    Large diameter threads are generally cut on a lathe with a single point tool. I have also seen them cut with a tool called a thread chaser which is like a chisel but with the end profile with maybe 10 v grooves with the thread profile. Takes a reallly good machinist to hand cut threads on a lathe with one.
     
  11. John Kasaian

    John Kasaian Member

    Messages:
    1,030
    Joined:
    Sep 24, 2002
    Get thee to a good old fashioned hardware store (NOT a big box home improvement emporium!) There is usually some old geezer wearing coveralls and named Gus or Lionel or Chester sitting on a stool somewhere in the back, with a coffee cup grafted to his hand, who has the answers which you seek, Little Grasshopper!:D
     
  12. Dan Dozer

    Dan Dozer Subscriber

    Messages:
    351
    Joined:
    Dec 10, 2004
    Shooter:
    Large Format
    Justin,

    I'm not sure what if anything the foam is designed for. It is fairly dense and comes in sheets that are 1/16" thick. Look in the area that has stuff like craft paper, felt squares, etc. At least that is where they are at Michaels. If all else fails, send me you mailing address and I'll send you some - I think I have some more left over.

    Dan
     
  13. John Koehrer

    John Koehrer Subscriber

    Messages:
    6,377
    Joined:
    Apr 3, 2004
    Location:
    Montgomery,
    Shooter:
    Multi Format
    Crafty people use it for crafty things.:D
     
  14. ragc

    ragc Member

    Messages:
    187
    Joined:
    Nov 11, 2006
    Location:
    Atlanta, GA,
    Shooter:
    Large Format
    [​IMG]
    [​IMG]

    Use glazing points from the hardware store. The mount is solid enough for permanent use.

    The one on the right is "stock". The one on the left was bent with pliers for the recessed thread mount for this old flangeless lens. This mounting is solid and allows the lens to be screwed off if necessary.
     
  15. c.d.ewen

    c.d.ewen Subscriber

    Messages:
    580
    Joined:
    Jan 27, 2005
    Shooter:
    ULarge Format
    Hey, Justin:

    If memory serves, you've been looking for this flange for quite a while. I remember seeing your first post and feeling guilty that I had one sitting unused in my 'hoard'. Take a look at the pictures and see if your shutter looks like mine. PM me and make me an offer for this flange. I've got a lathe, and can easily make another.

    JBrunner: there are a variety of ways to cut threads. Your post brought a smile to my face, envisioning a tap big enough to thread a flange for an 18 inch Verito :surprised: They probably exist, but it wouldn't be anything you could lift or afford.

    A bit of pedantry:

    With a lathe, the flange is mounted securely on a chuck and rotated. Through gearing, a groove-forming cutting tool moves through the flange at a synchonized rate, producing the desired pitch. The tool must make numerous passes through the flange, removing a small amount of material on each pass, to reach the proper depth of cut.

    A faster way of producing flanges is to use a milling machine and a hog. Picture a cutting tool something like your threading tap. With multiple cutting edges, it can cut multiple grooves simultaneously. Rotating at high speed, it's lowered into the middle of the flange, and the flange is moved sideways until the hog cuts into it to the required depth. The flange is then rotated, as the spinning hog is lowered through the flange. At the end of one rotation of the flange, the hog has been lowered one thread's worth, and each cutting edge lines up with the thread directly below the one it originally started on. The movements are usually under computer control to achieve the necessary synchronization. Hope that explanation is clear.

    Charley
     

    Attached Files: