Plugging Along - The 8x10 Pinhole Project.

In the September 4th post I had just gotten underway with a new project to build an 8x10 pinhole camera, having just received the film holders. Since then things have been progressing quite well, at least so far. As you were probably able to surmise if you read the first post I'm not one for starting out with an exact set of blueprints and trying to proceed in accordance with a set plan. I've done things like this enough times to know that along the way the need will probably arise to make allowances for things that didn't quite come out as expected and for new better ideas that only suggest themselves as the thing begins to take shape.Even if I had started with a clear plan it'd have been tossed by now.

The design I had in mind at the outset is based on the design of the 4x5 pinhole camera I made as a warm up project which itself was based on a completely original combination of design ideas I'd stolen from others. Rather than making a straight box my camera designs incorporate a cone out front like the Ilford-Harman Titan models, allowing front ends to be swapped out like lenses while keeping the weight down considerably. This last is particularly important with the 8x10 project as I'd say something the weight of a traditional solid box design would require a heavier tripod than I currently own.

The following sequence of photos should give you an idea of how thing have gone so far.

Here are the trapezoid pieces that form the sides of the cone cut from 1/4" plywood. As I suggested last time I did forego fibreglass construction used with the 4x5 cone. Working with the stuff was just too much hassle. Connecting the pieces to form the sides of the cone was as easy as Gorilla gluing the seams with masking tape to hold the pieces in place until everything was set. You can see the box that forms the main body of the camera in behind by the way. Since the Sept. 4 post they were glued up in a framing clamp and secured with L-brackets just as I'd planned. I may try fancier joinery someday. Maybe.

  

Once it was all a single piece I cut out a cover for it from a sheet of vinyl cloth from the local fabric store. I believe this stuff is intended for upholstery projects, The photo above shows the cloth covering on the back. The front is a burgundy colour. The pattern may seem familiar if you've ever looked into how bellows are made. 

The inside is lined with black felt. Normally of course a coat or two of black paint would do, but my current plans involve using the ends of the cloth to hold the cone to the rest of the camera from the inside, probably with Velcro. It remains to be seen how well this idea will work out, but even if it doesn't fly I have to say the inside seems much blacker than any paint would have rendered it. 

I capped it off with another piece of 1/4" ply covered with a maple veneer to match the maple body. Actually it doesn't seem to match as well as I'd hoped but maybe once everything is finished the difference won't be noticeable. Here at last you can see the burgundy exterior of the vinyl though it's in need of a good clean here. 

Inside the box is a bit of a ledge where it mates to the cone. The pieces are actually the leftover strips from cutting the slot on the back that the film holder slides into. Owing to the fact that I botched one of the sides early in the game, forcing me to cut another, I was left with enough to go all the way around the inside. 

And finally here it how the whole thing looks as of this writing.

To finish it obviously I'll need to add the pinhole. The box will need to be urethaned and painted black inside. Felt strips on the back surfaces that contact the film holder will serve a light seals. I'll need to create some means to secure the cone to the body which, as I said, will probably involve Velcro unless there are unanticipated problems with that. I'll have to add a tripod socket, which can be as easy as putting a t-nut in place but maybe I'll come up with something more elegant. Finally something has to hold the film holder in place on the back and allow it to be released. In the 4x5 version this involved Velcro straps but I'm thinking of changing this up too. Velcro strips seem like an affront the natural wood finish. I'm thinking of adding a vertical bar that can be tightened or loosened with something like thumbscrews or wing nuts. As always I'll keep you posted.