| The Two Basic Types of Leaks |
| By Curt Altarac |
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There are basically two types of pad leaks on any woodwind instrument. The cause of some leaks may be mechanical in
nature, for example: friction inhibiting a key's function, a bent rod, screw or body. Problems like these will cause
a leak, however, the leak itself will either be a Pad leak or a Timing leak.
Pad and timing leaks are sometimes symptoms of another problem, and sometimes the entire problem. The job of the
repairperson is to understand what type of leak they are dealing with and the possible solutions.
Pad Leaks
Pad leaks are the first leaks that we need to deal with when doing woodwind repairs. It is impossible to repair any
timing leaks before the pad leaks are under control. Pad leaks can only be addressed one pad at a time.
A pad leak occurs when one part of the Pad touches the tone-hole before another. When the pad closes, the entire pad
should come in contact with the tone-hole exactly at the same time around the circumference of the pad. I am often
asked is this a leak?. The answer is always yes.
All saxophones leak because it is impossible to get a piece of leather-wrapped-felt and a ring of metal to contact at
the EXACT same moment around the diameter. As a repairer you decide how exact you want to be.
The more exact you are the better the instrument will respond and the easier it will be to set the pad timing.
Timing Leaks
Pad timing is when one pad to closes against a tone-hole while operating a linkage that lowers another pad at the same
time. When pad timing is not properly set, a timing leak results. Although pad timing can sometimes involve many pads,
it is best to only concern yourself with 2 pads at a time. Often pad A will close pad B and pad B will close
pad C. In this case make sure that pad A will close pad B at the proper time and then check the timing between
pads B and C. If there is not too much give in the mechanism, pad A and pad C will close at the same time.
Because Pad Timing is adjusted by minute changes in spacing material between keys, it is best to use a material
that will hold an adjustment. The traditional material for this has been cork; but I find
TechCork to be much
more useful. It does not compress as quickly as cork, yet offers nearly the same or better silencing properties.
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