View attachment 186525 Wellllll.........I’ve made hundreds of bellows and I’m going to give you My method. Now, this is for square or rectangular bellows. Pyramid bellows are tough to make. I don’t go there. OK. Step one. Made a long open end box from plywood. Wrap box with sheet of thin plastic. Cover with 100% cotton black thin cloth, with ends extending past the box a few inches. Glue the seam with Elmer’s glue. Step two, cover all the cloth on the box with black construction paper, glued on with Elmer’s. Let dry overnight. Step three, the chipboard dividers are cut long grain, with the ends cut at 40 degrees. Space these 1/4” apart (important). Keep these straight on the box using a right angle square. Glue on with Elmer’s. Let dry under a weighted board. Step four. Using a rotary wheel tool score the paper between the spacers. Let this All dry well. Step five. Lightly sand the cardboard strips to knock of “fuzz” and loose fibers. Step six. The outer covering is thin black rip stop nylon. Joann Fabrics sells this. The glue used now is Weldwood original contact cement. Stand the box up, apply a generous coating of contact cement. Spread the cover ou a flat surface and apply the contact cement. Let dryto a flat look. Now! You get One chance here to do it right! I lay the box on its side up high so I can hold the covering by the corners. Start the cover on the opposite side of the inner cloth glue seam. Apply carefully so as to avoid small wrinkles. Press on firmly with your hand and using your thumbnail press toe covering all into the edges of the strips. Step seven. Pull completed bellows up on the box, creating the folds as you remove the cover. Step eight, compress and sxpsnd the bellows to loosen them a bit, then fit the wood frames in and staple the bellows on. Trim off the excess. •••••. It takes experience but this method works. The cotton cloth and the ripstop neither are fully lightproof. The construction paper inner cover..That’s 100% lightproof.