Hi everybody,
there's anybody who succesfully built a plane lensboard such as mine calumet met al one? I was thinking to use a soft mould to 'print' the back of the original l ensboard and try laminating with epoxy resin in thin layers using the vacuum bag ging system. When the resin packs you just have to cut the board at his proper s ize and drill the hole at required 'copal' size.
Any (disgusting as well) comment??
Thanks and ciao Fabio Pollero Savona/Italy
I've made several lensboards for my Calumet CC-400 camera from 1/8" aluminum tooling plate.
This isn't a difficult material to work - a hacksaw and files or carbide woodworking tools are suitable. I sand both sides of the board with 80 grit sandpaper and paint the inside with flat black spray paint. If you use a power sander with this relatively coarse sandpaper, an attractive matte finish is obtained on the unpainted aluminum.
I need to make one right now, and will probably use scrap aluminum plate from an electronic "rack panel". I've made them in the past by gluing together two pieces of fiberboard, one slightly smaller to fit the internal cutout and prevent light leaks. The epoxy method would probably work, but seems like a lot of work. You could certainly make a mold from 2-part RTV and cast a new lensboard with epoxy. Be careful about the filler, as many dye type fillers transmit UV and/or IR! Painting it will work, but chips in the paint might leak light. Actually, that method might be quite good, but I don't have an original lensboard to copy.
The lens boards for the Bender 4x5 kit ( my first view camera) are made of black plexiglass. When I needed additional boards, I got a sheet of black plex and cut my own. You can cut the stuff with woodworking tools, the lens hole can be drilled with a cheap "butterfly" wood bit. When the fabrication was complete, I sanded the board with fine grit paper to make it a flat finish. I don't see any reason this material could not be used for other types of lens boards.
I've had good luck with 1/8th inch hobby board, a plywood that you can pick up at most hobby stores. At least, this works well for Deardorff boards and such like.
The lensboards i use on my linhof tech V were made by myself using a material called MDF. It is sintetic wood, and should be available at any home improvement store. Once I had the model, I cut it and used a dremel for slots and finish.
I just bought a 180mm-355mm convertible symmar and I'm planning on making the lensboard myself while I wait for the lens to arrive.
My question is how critical the thickness of the material is for this type of lens? I would assume very critical, since the front and back lenses work together to achieve proper focus. Does anybody know what is the exact thickness of a lensboard for this lens? Also, I know that the shutter is a compur, but not the exact size. How can I know what shutter goes with that lens? I will know it in a couple of days, but I can't help my anxiousness.
At last, is the hole drilled dead center in the 4x4 board?
The mounting hole for the lens will have to be thin enough to allow the shutter to be attached by the retaining ring. The rear lens element screws into the shutter, so if the hole is big enough for the shutter to mount, the lens elements will be fine. If you are using a thick board for the lensboard, you may have to use your router and route out a channel around the lens hole, to get the material thin enough to get the retaining ring on the back of the shutter threads. Some older lenses mount with a mounting ring that attaches to the front of the lensboard with a flange that accepts screws. In this case, you just need to make sure your lensboard hole in the middle is as big as the rear element on the lens, so you won't restrict the light.Originally Posted by Padu Merloti
The Schneider Symmar 180mm f:5.6 / 315mm f:12 convertible is in a #1 shutter.
The lensboard should be thick enough to allow the retaining ring to get a good grip on the board, which is a very wide range. The rear cell of the 180/315 had a diameter of 45mm, so you will need to unscrew that cell to mount the lens on a lens board.
A second for Birchwood hobby board that works very well -
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