How to get the right angle on stiffeners for tapered bellows?

I'm making a tapered bellows for my 8x10 project, and I'm having a hard time figuring out how to draw the angles at the end of the stiffeners so they match nicely to the next side of the bellows. Does that make sense? Any suggestions?

Draw the pattern in some sort of computer program and then out put it directly onto what ever you are using as a stiffener. My favorite way to tackle this now is to build the pattern in adobe illustrator and then use a laser cutter to cut all the stiffeners out panel by panel. I have also used inkscape or sketchup and output with an inkjet printer onto the stiffener substrate, then cut by hand. Im in SLC if you have any questions, drop me a message

I cut mine in 45 degree angle and they fit fine. They don't need to be laser perfect. For my recent bellows for the Gundlach Wizard, the ribs are cut at an angle for the tope and bottom panels, for the side panels the ribs are cut at 90 degree angle. I use a rotary cutter on a healing mat.

JB Harlin has a good pdf on bellows making here: http://www.jbhphoto.com/articles/bellows-building/

Your specific question is well answered there. I'd think carefully about the initial setting out of your bellows though, as the method isn't foolproof. I followed JB's directions and ended up with a bellows that was square one end and rectangular the other, depending on how the folding was initiated. I think the problem is in his recommendation that the dimensions for the top/bottom and left/right panels be taken from the outside and inside measurements of the frames respectively. I feel that if you want a square bellows you should use the outside dimensions only. In fairness to JB, he strongly recommends making a trial out of stiff paper first, which I being impatient didn't do.

I have a tapered bellows made by a UK company that used to be called the Camera Bellows Company. And the stiffeners have square ends

Alan

I read somewhere that in the history of bellows making the shape of stiffeners has changed from square in the early days, to angled as is now common.

Do the ends of the stiffeners, square or angled, change how thick the bellows is when compressed for folding up a field camera?
I've got a 100 y.o. 8x10 camera project that needs a bellows to become operational. I've been kind of stalled out at this step. I built an 8x10 square bellows with no taper, that was tedious, but have been a little intimidated by the need for this bellows to be a pyramid and having to cut all those stiffeners etc.