But I found if I don’t whine too much and just do it that bellows only take a few hours. I had just enough of the old Porter’s fabric for one more set of bellows, so no point in asking me where to get the cloth these days- I wish I knew. For the patterns I’m using 90lb Revere Platinum paper- they need to work out the manufacturing issues with this stuff before I waste any more precious metals printing with it… glad I only bought 10 sheets. But 22″x30″ is a good size for 5×7 bellows patterns. Plus the sizing helps keep it from buckling and deforming when the glue hits it. And hey, the bellows should be archival. @-]
Layout. I used the entire length of 32″ paper for the bellows as the pleats will take about 20% off the overall length. It saves some time drawing laying out by reversing the patterns, because the when the pleat on top pattern is folding up, the adjacent pleat on side pattern is folding down. Reversing the patterns offsets the ‘up’ fold lines so when flipped to make the bellows the pleats fold correctly. (With a tapered bellows the up fold has to be bigger that the down fold in order for the bellows to get bigger.) The problem with this layout method is the lines in the spacer part (the parallel lines with the butting arrows that separates the patters) become confusing- all the lines don’t align. I need to remember this next time and only tick off the major fold lines into the spacer area. I used the square to confirm that they do in fact align correctly, regardless of the marks, when the line is continued to the ‘down’ fold lines of the adjacent pattern (arrows from center line of 1st pattern to edge of 2nd)
Punching and cutting fold lines. I stack all four together to save time. The spacers are perforated for easy removal after glue down on the top and bottom patterns, and removed completely from the side patters. I like using these full panel patterns more than the individual stiffeners- maybe a little more time and care cutting them out but much easier for me to glue to the fabric than trying to keep all those individual strips aligned correctly. Also, putting less material in the corners does help the bellows collapse into the thinner spaces that folding cameras require. This one should collapse to less than 1/2″ when done. But I still might try incorporating the actual peaks for the corner folds into the patterns if I ever make another bellows- it is a little difficult to get perfectly crisp factory corners without card stock going all the way into the corners. I did try a hybrid once with half the patterns cut into peaks in this version, but had the geometry wrong on that version so it was doomed from the start.
Glue down. I think it’s easier to glue up only half of these longer patters at a time. The top is weighted to keep it from slipping, the bottom half is sprayed with glue and flipped down.
The last pattern spans the seam, so it was easier to glue this from the side. I located the spacer in the tack from the overspray from the panel next to it, then sprayed the glue onto the fabric. Had to tape the full edge of the fabric because the stuff wants to curl very badly, especially when the glue hits it. Once that piece is in, it’s time to join the seam, then remove all the spacer strips before gluing the liner in. The watercolor paper worked very well- didn’t deform or buckle with the moisture of the glue and seems to have just the right thickness for this size bellows. For reference, the assembled thickeness of bellow material, pattern and liner is .9mm (9/10ths of a mm).
I glued down the liner on just one side at a time. I held the bellows down with tape, masked off and sprayed the pattern and the liner, then use a long thin straightedge like a screed to roll the liner over the pattern. This helps to smooth out the fabric before the glue grabs, helping to eliminate any bunching and wrinkles. No need for a mold or form this way.
Then, turn inside out and fold. Impossible to take pictures during that shit storm so… presto chango-
Rough fold, before clamping. I need to make the frames before putting under weight- the bellows can deform easily if clamped and weighted without the support of the attached frames.
Turning it inside out is sort of a leap of faith- you seem to be trying to destroy the fruits of your hours of hard work. But a little smoothing with a warm iron makes it alright again. The outside seam need some more glue at this point. I also use a bone burnisher to work the fabric together in the creases between the folds to make sure the glue is making good contact before starting to fold. Folding is mostly automatic- just be sure to start the folds with the correct pleat- the wider ones go up.