|Glueing on the Bellows
I found that the method of glueing on the bellows cloth by holding the bellows
vertically in a vice (as shown in the video) and starting from the front
was very fiddly and inaccurate. Accurate placement is rather hit and
miss because you are working from the outside and can't easily see the position
of the cardboard stiffeners in relation to the edges of the boards. It's
also slow, the glue gets in places it shouldn't, and the glue has started
to go off by the time you get to apply any clamps.
I found it was very much faster, easier and more accurate to do it
the following way, (and you don't get glue all over your fingers neither!).
Before starting, it is best to make sure that the front cardboard stiffeners
are exactly the same width as the bellows boards, and make the two small
cuts in the front corners of the cloth that allow it to fold outwards along
the top board (see John's video if you don't know what this means). It
doesn't matter if the front cardboard is not exactly the right width, as
long as you take this into consideration when positioning the cloth on the
boards in the following procedure.
Lay the bellows cloth flat on the bench. Apply glue along
one long edge of the bellows (both boards) and also along the front edges.
Place the long edge of the bellows carefully on the cloth, lining up
the cardboard exactly between the two bellows boards. Check that the
corner is in the correct position. Do not glue the front on yet.
Now apply glue along the upper edges of the boards. Fold the cloth
up the front edges and check that the cardboard is sitting in the correct
position. Finally, fold the cloth over the top edges and line the cardboard
up with the hinge end of the boards. Pull the cloth tight and press
it well into position all around, then place a heavy book on it and leave
This method is very fast. I did a pair of bellows and a reservoir
in under 5 minutes, with no fiddling about at all. The weights or clamps
can be applied very quickly, leading to a stronger joint.
Note that the bellows remain fully open throughout the entire operation,
there is no need to close them or crease the cloth, as it tends to unstick
When thoroughly dry, trim the ends of the cloth, fold them over the bellows
hinge and stick down.
Leave for at least 24 hours for the glue to fully cure before testing the
bellows or putting any pressure on them.