The Spring Back

The most complex part of a large format camera is the spring back. Not that it is particularly complex, it is just that the rest is rather simpler.
Before I started cutting up wood I wanted to make sure that all the parts fit together properly. To do this I have made a spring back using materials I had readily available.
The grey parts are cut from 9mm nylon, the brown parts are from a 3.2mm composite material and the green parts are 1.6mm FR4 PCB fibreglass.
The fibreglass parts are the big surprise here as they are the springs. Usually, the springs would be made from spring steel and once I have perfected the design, I will have some made. The fibreglass springs do work very well though.
All of these parts were cut using a CNC drill/router which I have at work. This saves a lot of manual labour and allows me to try out various ideas.

Spring Back

I was planning to use the spring back from my existing non-folding camera for this design but I have decided to keep the old camera intact and build a new spring back from scratch for the new camera.

The old camera used a cast aluminium back which I bought on eBay. The new back will be wooden and have a lower profile. This will have the added benefit of moving the film plane further forward which will require a bit more bellows extension which in turn will aid any movements required.

As I am primarily a landscape photographer, I tend to prefer wider angle views. However, I don't have much of a budget for lenses and currently I only have two: A Zeiss Tessar 135mm from a 9x12cm plate camera and a Rodenstock 127mm from a Polaroid roll film camera.
I intend to give this camera sufficient extension to use these two lenses and also make it capable of taking 90mm and 210mm lenses which I may buy in the future. The maximum bellows extension will probably be around 300mm (12") but I don't expect I will ever use a lens that long.

Some Plans

When I made my first non-folding 5" x 4" camera I didn't bother with plans. I just made parts to fit as I went along. In order to make a folding version though, I decided to draw the parts up on CAD to ensure that everything fitted together properly. In order to get an idea of the mechanisms involved to get a camera to fold up properly, I looked at a lot of manufacturers websites and some DIY camera builders' websites.
One of the best resources for DIY view camera construction I have found is http://www.raymentkirbycameras.co.uk/index.htm
The 'Workshop' section shows construction ideas and there is a simple downloadable plan which I have used to base my plans on.
The back is basically a box 180mm x 180mm and 50mm deep. It is made from 6mm thick wood giving an internal dimension of 168mm x 168mm. I made the 'C' plates to hold the rear of the bellows (as described below) to comfortably fit into this space.
I was initially going to cut down the plastic moulding at the front of the bellows slightly but in the end I decided to keep them standard. That way they can easily be replaced if neccesary (although four holes do need to be drilled in the corners).
The front mounting plate is 139mm x 139mm so allowing for an opening of 140mm x 140mm and using 6mm thick wood, I ended up with a front 152mm square. This is larger than most folding view cameras but as I am only going to use limited movements i.e. front rise and/or tilt, I don't think it's going to be a problem.
The folding mechanisms for front and rear are based on the design in Rayment Kirby's website as is the focussing bed but with a few modifications of my own.
If anyone is interested, I have some Autocad drawings which I could send to you in either DWG or DXF format.

Start With The Bellows

I built a non folding 5" x 4" camera a few years ago. It was bulky and heavy (and, obviously, did not fold up).

Ever since building it I have wanted to improve upon it and build a lighter folding version.

I bought a set of bellows from e-Bay for 99p (about $2) which came from a Sinar Norma 5" x 4" monorail view camera so I decided to make the camera to suit the bellows.

The Sinar bellows are not as tapered as I would have liked but since they were so cheap and I don't have to make any bellows myself now, I am going to use them.

There is a plastic moulded plate at the front and rear of the bellows. The rear plate has a rebate around it's perimeter which I assume is the way it fits onto the Sinar rear standard. This rebate is 2.4mm wide. I made six "C" shaped pieces from a laminated resin material 0.8mm thick. These are overlapped three deep to fill the slot in this manner: [ ] with the inner pair rotated 90 degrees so the joins do not all line up. There are twelve holes around the periphery of the plates to fix the bellows to the rear. The laminate material is white so I have stuck a matt black vinyl onto the outer pair to make it look a bit better.