Mounting a tiny brass lens

[Benno Jones]

I have a tiny (back of mounting flange is about the size of a half dollar) brass lens that I want to mount for my Shen-Hao 4x5. I have made a Technika-style lens board from thin model airplane wood and covered it with 4 coats of black paint on both sides (hoping that's light-tight but I'll do a test to be sure). I have yet to cut the lens hole, but that should be no problem. What I need some ideas on is how to mount the lens. It's the kind that has a built-in flange with holes for screws, but the lensboard is so thin I doubt that I could get anything to hold. I've thought of small machine screws with nuts (painted black on the inside to eliminate reflections), but thought someone out there might have other suggestions. I hesitate to glue it because I may want to remove the lens at some point.

Thanks...

[rknewcomb]

I have used number 2 machine screws before as you described, worked fine. I did cut them off to the proper length so they don't stick out so far. The trouble is that many local hardware stores don't carry screws smaller then a number 4 or 6 and those are way too big. Got my online.

[Pete Watkins]

Don't forget to use washers as well. When you've finished paint the nuts, washers and threads on the inside black.
Pete.

[Gene McCluney]

As mentioned above, the most secure way to mount a small lens flange on light wood is with machine screws that go completely thru the wood and are secured with washers and nuts on the back side. The washers spread out the pressure from the nuts so the wood will not tear. You would pre-drill holes for the machine screws, and after assembly, you would spray paint the whole assembled unit flat black on the inside. For very tiny small machine screws, washers and nuts, go to Radio Shack. They have small packets of this type of hardware, just the right size, as they are used in electronics projects.

[wclavey]

I would like to make a suggestion as well - - about your lensboard and not mounting the flange.

I have made a number of lensboards out of thin airplane model wood or very thin doll furniture plywood, and I have cracked or broken 1 or 2. I have started adding a thickening layer to the back of the lensboard made of thicker wood where the outside dimensions of the layer are small enough to fit into the throat of the front standard and it has a hole in the middle large enough to accomodate the mounting flange of the lens. I mount the lensboard on the standard and then go in through the back of the camera and glue the stiffening layer in place through the throat of the front standard. This makes the board very strong and has the added benefit of creating a light trap. Then I cover the entire thing with several layers of flat back paint.

I have never broken one made this way. I do not have any woodworking tools beyond a drill, a coping saw and a hand sander and it is not hard to make these this way.

[Benno Jones]

Thanks for the comments. Looks like machine screws/washers/nuts/more black paint is the way to go.

[Benno Jones]

Found appropriately sized brass screws & nuts at my local Ace Hardware! Lens is mounted, now if only it would clear up enough to have some decent light so I can see what this lens will do.

[Murray]

Another good source of tiny hardware are the hobby shops that sell the airplane plywood.

I have some lenses that appear to have enough only threads for a metal plate (like the integral plate in the bellows of old folding cameras).

It looks like I have to make a thin metal plate, then screw that to a thicker wood one. (double in my case for Crown/Speed).

murray