This is not necessarily the easiest way, but It takes into consideration the requirements for a substantial and trouble free method which applies to all types of pneumatics, regardless of how they were previously hinged. This method of hinging eliminates the need to collapse the pneumatic before gluing the hinge end, since it defies the problem of becoming "hinge bound".

1. C-clamp a carpenters' square to the top of the work table.

2. Place five pneumatic bottoms, with the glue side down and hinge away from the square, and the first side against the inside of the square.

3. Place a 1/2" wide strip of adhesive backed furnace duct tape, overhanging the hinge end half way. The length would be the combined width of the five pneumatic boards. Press this down firmly with your finger tips. Use a permanent "magic marker" (felt pen) to make a fine line along the edge, indicating the end of the board so you can later see where the center line is.

4. Invert these and butt the moveable pneumatic leafs hinge end, with Interior side down, into the remaining adhesive tape. Turn the assembly over again with taped side up.

5. Remove the backing of 1/4" X 1/8" thick felt-tape, to expose pressure sensitive area. Press this down on one side of the line made by the felt tip marker, the same length as the duct tape. The felt-tape should be stuck over the thicker of the two pneumatic boards.

6. Glue a 3/8" diameter X 1/8" thick woven felt punching on the thickest board so there Is at least W between the edge of this punching and the front edge of the open end of the pneumatic. Glue this punching with plastic glue, centering it between the sides.

7. Fold the pneumatic boards over with internal sides facing each other. Press together. Cut the five pairs of pneumatic boards apart with a razor knife.

8. Stack the five pairs one over the other with hinge ends together. Clamp these together in the middle with a C-clamp or a 3" jiffy spring clamp. Before final tightening, if a C-clamp is used. set the hinge ends down on the work table and tap the opposite ends with a hammer or a rubber mallet to force the ends of the boards at the hinge end to come evenly together. Then lay on the side and tap, to correct any slight misalignment in that direction.

9. Smooth a thick coat of plastic glue over the hinge end of the block of five clamped pneumatics. Leave standing In the upright position and transfer to an oven at 150 degrees until the glue turns clear. Remove and add a second coat of the plastic glue and replace In the oven until that It Is dry; note the time, and leave in the oven for an additional two hours to fully cure. An oven curing is not necessary, but it saves time. It only air dried, clamps may be removed, but must cure at room temperature for two full days after turning clear, before going on to the next step.

10. Slice the pairs apart with a razor knife.

11. On each of the hinged pneumatics, taking one at a time, turn the hinged end toward you and raise the top leaf perpendicular to the bottom. While one hand holds in this position, use a knife with the other, to cut against the bottom board's interior surface through the duct tape and felt, from about 1/4" from the side edge, angling to the hinge crack. The corner of the upright leaf is to be used as a guide for the knife blade. Invert the pneumatic and repeat this for the other leaf. Then taking the pneumatic unit in hand, pull off the four severed right angle triangles of the waste material using the tip of the knife blade as an aid to peeling these off. This will leave the side crack open all the way to the hinge crack. The pneumatic is now ready for covering with pneumatic cloth.

Although the internal bumper felt was not a fixture of some original pneumatics, which normally had a closure-stop elsewhere in the linkage, it does serve the purpose of balancing the thickness of the felt inserted in the hinge end; but more important: it makes it impossible to fully close the pneumatic leaves upon the pneumatic cloth, in the process of handling it. This one feature will save the material from premature cracking in the front folds several years from now. The greatest common fault in pneumatic recovering has always been to accidentally or on purpose, put a hard crease on the folds, rather than rely on the natural vacuum force to determine this, which will spread the folding wear over a broad folding trough, increasing the wear life of the material by several times at this point.