Construction of conical bellows with square corners

[Andrey Donchev]

Hi, I'm trying to find a geometrical way for construction of a conical bellows with square corners, but for now without success. Please help!

Andrey

Donchev Cameras

[vinny]

Did you ever do a video of the finger joint cutting for your frames?
I'd like to see if there is a better way than I've done it.

[Len Middleton]

Hi, I'm trying to find a geometrical way for construction of a conical bellows with square corners, but for now without success. Please help!

Andrey

Donchev Cameras

Do you mean tapered bellows where it is square or rectangular in section (as viewed from inside the bellows), but small at the lens board end, and larger at the film standard?

Or do you actually mean round in its section view i.e. looking down the bellows from the back of the camera?

[Andrey Donchev]

Vunny, I have not, but i plan to do it very soon. Will be happy to share it with you.
Len, The first. Bellows similar to the Deardorff's V8 bellows.

[Steven Tribe]

I have done this, but with 4 pieces of material which are then joined with overlapping tape pieces. If you have the old bellows then you just reproduce the top piece twice and then one of the side pieces - also twice. Cutting out the bellows in one piece would require and awful lot of skill and material of considerable dimensions, both in length and bredth!

If don't have the old bellows, you will have work like a dress maker with large sheet of paper and calculate the length of the "down" folds so that after X number of folds you come down to the reduced front standard glueing fitting dimensions. You make an awful lot of lines representing inner and outer foldsIt is a good idea to make the First and last folds longer than usual to have enough length for glueing.

My experience is that bellows is forgiving for about 0.5mm plus or minus - above that, the appearance will suffer.

Not quite sure that a conical square fold bellows would look OK! My experience is with the angle folds.

[Len Middleton]

I remember seeing information by J.B. Harlin, and hopefully this is helpful: http://www.jbhphoto.com/wp-content/u...ingjbh2008.pdf

[Andrey Donchev]

We're not trying to replicate an old bellows. We'd like to build a new bellows for our next camera. In some ways it is more convenient then a bellows with oblique corners.
Its construction, though, prove to be much different and after a week of brain storming and investigating every source I could find We're still nowhere. Saw the Deardorff's bellows pdfs, but for now I haven't found any geometrical way of constructing its pattern.

[Andrey Donchev]

Len, J.B. pdf is for bellows with oblique corners. I need information for bellows with square corners.

[Len Middleton]

Len, J.B. pdf is for bellows with oblique corners. I need information for bellows with square corners.

Andrey,

Sorry was not aware of that part of the requirements, nor the differences in construction.

What is the benefits of square corners, versus oblique corners?

Good luck in your efforts,

Len

[Andrey Donchev]

The square corners bellows construction makes possible to use different ribs width and by using narrower bellows ribs in the end of the bellows, near the film standard, the camera could be constructed smaller then otherwise. That's why the Deardorff camera is comparatively smaller by size then other 8x10 cameras.