Re: Square bellows?
Richard Knoppow (dickburk@ix.netcom.com)
Fri, 21 Nov 1997 02:01:54 -0800
At 01:07 PM 11/20/97 -0700, Wayde Allen wrote:
>On Thu, 20 Nov 1997, Bob Szabo wrote:
>
>> Ive read a lot of great info about bellows from all the info here my thanks
>> to all who have contributed. However my interest is in wetplate cameras and
>> would like to make square bellows. Were they folded differently. Is there a
>> source for pre 1880 style bellows making? I have not examined a lot of
>> originals but understand that not only do they not taper but the corners
are
>> different too. Am I correct in this? Any help will be appreciated.
>
>I have an article on bellows making that was Xeroxed from an old book.
>I'd have to check, but I think it may be from around this point in time.
>The information is similar to what you'd get from the View Camera magazine
>article or Doug Bardell's web site. It does have a nice, but fairly
>tedious method for laying out the fold lines using geometric construction
>with a compass.
>
>Fundamentally there is no real difference between a straight walled and
>tapered walled bellows. The construction method is basically the same and
>the folding is the same. In either case, the valley of one side is the
>peak in an adjacent side. The difference is that for a tapered bellows
>the rising half of the fold is shorter than the decending half. In a
>straight walled bellows both sides have the same dimension, and as a
>consequence these are a bit easier to make. I'll try to give you an ASCII
>diagram. Hopefully our mail systems won't shift the characters and
>screw up their relationships.
>
>
>Straight Wall Bellows (side cross section):
>
>
> \ /\ /\
> \ / \ / \
> \ / \ / \
> \/ \/ \ NOTE: four units both down and up
>
>
>Tapered Wall Bellows (side cross section):
>
>
> \
> \ /\
> \ / \ /\
> \/ \ / \
> \/ \
> \ NOTE: four units down for every three up
>
>If you notice the fold "panels" on the straight walled bellows are all
>four slashes in length. In the tapered bellows the rising distance from
>the bottom of the trough to the top of the next fold is shorter than the
>decending distance from the top of the fold to the bottom of the next
>trough. In this diagram you go down four slashes and only up three. This
>is in fact the reason that it tapers. The fold corners are fundamentally
>the same.
>
>- Wayde
> (wallen@boulder.nist.gov)
>
>
Actually there are two methods of making the folds and corners in bellows
so "square" may have two meanings. One is what you describe above. The
other has to do with the appearance of the corners. In the most common
bellows the corners are truncated. In the other type the corners are right
angles. This is the type of bellows found on Deardorf cameras.
----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com