Need help with bellows

[Albert.Adderley]

Hi I have given myself the task to make a 10x8 camera just need a few answers on bellows.
I have found various plans to use and built my frame from a mixture of them I have just the length of the bed to work out to match length of bellows.
Now I need some help working out my bellows.
I want to use tapered bellows and having problems working out the length I need and also how much more material than length I need to allow for the corrugations.
I would like the ability to be able to do macro as well.
I know I am new to this but as I have a lot of time and nothing to do thought this would be a good idea.
If I haven't given enough information please tell me as I don't know what else you need
Al

[IanG]

Albert, I've made tapered bellows and have a few patterns, I can also adapt the patterns quite easily.

You need to decide what maximum extension you want first, bellows can be made any size to fit. My main 10x8 camera has 36" extension, the other about 27".

Ian

[Albert.Adderley]

I was thinking of a meter as I have some material to hand at that lenghth
The front of the bellows will be to fit in an opening 205 mm square was supposed to be 200 but a bit bigger. The rear of the bellows need to fit into an opening 390mm I know it's a bit big but I got some one to help with the back part and he got carried away a bit and had it finished before I could see what he had done.
Plus the option to do lager wet plates when I get better
Any thing else you need
Al

[IanG]

Because the cloth has to be cut in one piece and there's a taper, plus the fact they never get quite fully opened and you lose a bit for fitting etc, you need material that's about 20-25% longer than the planned extension to be on the safe side.

See the attached file, there's 5 sides because these get trimmed to allow the overlap and join. Can't remember what size these were for, I drew this pattern for someone else.

Ian

[Albert.Adderley]

Thank you Ian I get the idea what material do you recommend for the bellows I was thinking of blackout material painted black as I have only seen it in cream for the inside
But not sure of the outside?
Al

[IanG]

I've emailed you.

Ian

[Dan Dozer]

Hi Albert,

I've made many bellows myself for cameras up to 8 x 20. I have used black out material on the inside painted black as you describe. Since it's lightproof, the outside material doesn't need to be anything special. I found some black "egyptian cotton" at the fabric store that was pretty tight weave and very thin. It worked out pretty well.

[kb2qqm]

http://www.sandehalynch.com/index.html

[norman valentine]

I have made bellows using blackout material, the problem with painting it is that the paint will flake off. I use the blackout material on the outside with plain black cotton inside. The second bellows that I made was painted, which is how I found out about the flaking problem. For my current bellows I have dyed the blackout material with Dylon. It is not as dark as I wanted but is better than stark white and will not flake.