Answers to some commonly asked repair questions at HMT...
Thanks to contributors to the Squeezebox Newsgroup, especially Alan Polivka, for much of the advice given here.
Q. My accordion has a little air leakage at one place
where the bellows frame joins the accordion. I know that this
is coming from here because when I apply pressure it becomes
air tight again. On an older accordion when I had this problem
I just ran a piece of electrical tape over the affected area.
A. It sounds as though the bellows gasket is worn out.
This is a very common problem. The gasket should be replaced. Specially made accordion bellows gasket material is available, and is the best solution. In a pinch, you can temporarily
replace the entire gasket with the appropriate size of adhesive-backed
The problem with weather stripping is that the foam rubber
will crumble after aging. Many folks use it anyhow. The accordion bellows gasket is much longer lasting.
How to Apply New Bellows Tape
Use ordinary white glue for putting on bellows tape. The standard
technique is to spread a bunch of the glue out on a board. Then
lay the strips of tape on the board and press them onto the glue
(with a piece of wax paper on top of the tape, to keep the glue
from getting all over your hands). This gets just the right amount
of glue on the tape. Then apply the tape to the bellows.
If you are using ribbed bellows tape, be sure that the diagonal
ribbed pattern is going in the same direction from one fold to
the next. The bellows need to be pressed while the tape dries
(under quite a bit of pressure, e.g. at least 50 lb.). Put strips
of wax paper between the bellows folds while the glue dries so
that they do not stick together.
Use 3/4-inch wide tape unless you are putting new tape over
the top of old bellows tape. In that case, use 1-inch tape.
Tips for Reed Skins (Leathers, Valves, Flaps)
Q. Some of my reed leathers are curled up, and the
reeds are making a funny noise. Do I have to replace all of them,
or is there a quick fix?
A. A badly curled reed skin can be removed and straightened
by creating a sort of spine down the center (by pressing into
the leather with a sharp pointed object to create little bumps),
then shellacked back into place. Some repairmen use a piece of
metal with a slot in it and a blunt ice pick to do this reshaping.
The spine adds to the stiffness of the skin. Avoid ridging the
free tip of the skin.
It is better to replace the reedskins rather than try to condition them, but if you must, use a leather conditioner
that contains no silicone (such as neatsfoot oil). That is because
the silicone can destroy the adhesive holding the skin in place.
Saliva or anything containing water is not recommended for use
with PA reed skins. The reason is that piano accordions with
non-stainless steel reeds (which is most PA's) depend on the
reed skin to absorb moisture in order to prevent the reed tongues
from rusting. This is not a problem if you live in a very dry
climate. But for the rest of us, it is a concern over time.
Q. What about valves that are missing entirely? Are
you better off ordering them from a supplier, or can you make
A. The smaller piccolo reeds in a PA are not intended
to have any reedskins at all.
It is extremely difficult to get leather with all the right properties
for reed skins. Even the old time pro repairmen usually get their
leather for reed skins from accordion supply houses rather than
trying to pick it out themselves at a leather shop.
The standard adhesive for use on PA reed skins is shellac. It should be left out to dry until it is sticky.
It holds leather to metal well enough and it dissolves easily
with standard solvents when you are doing a reed overhaul. Since
accordions are designed to be overhauled (re-waxed, new skins
and re-tuned) every 20-30 years, this is an important consideration.