[Harp-L] Rattling Valves

["Brendan Power" <bren@xxxxxxxxxxxxxxxxx>]

In answer to Mark Kegel, who reported rattling valves on the Suzuki
ProMaster half-valved diatonic: all my harps (diatonic and chromatic)
are half-valved and I introduced the idea to Suzuki in the first place,
so hopefully I can help. 

Valves are very delicate but useful components; it's worth learning how
to work with them if you play valved harps, as problems will inevitably
occur from time to time. Admittedly this rattle does crop up on some of
Suzuki's ProMasters, but there are ways to fix it if you are willing to
spend a little time. 

I find the cause is invariably the seating of the valve at the base. It
seems to be far more critical on diatonics than chromatics, probably due
to their superior intrinsic airtightness. If you pull off a valve on any
brand chromatic you'll usually notice that the glue has seeped slightly
down the sides of the slot. This generally doesn't cause problems on a
chrom, but if it happens on a diatonic, especially in the lower range of
Richter harp, the valve may rattle when you draw. This is because the
glue seeps down unevenly, so the valve is held a tiny bit further down
one side of its length than the other. This means it doesn't lift evenly
on both sides and torsional vibration occurs. The ensuing rattle is
annoying, I agree! 

Sometimes the problem can be fixed by CAREFULLY poking a thin sharpened
wedge under the valve to prise it off the sides of the reed slot. Be
careful not to prise it off altogether!

If this doesn't work, disassemble the harp and pull off the offending
valve(s). Polish off the residual glue on the reedplate until it is
clean. Deposit a drop of Superglue on a tray or similar surface, and dip
a thin piece of wire into it. This will pick up a tiny drop of glue that
you can put on the reedplate about 1-2 mm behind the reedslot.

Pick up a new valve with a pair of tweezers and slightly kink at the
base tend (to make the valve press down firmly when it is in place - a
trick I learned from Rick Epping).

Line up the valve over the slot, place the free-end down first, then
carefully place the base of the valve on the spot of glue and hold down
gently with the tweezers. It should stick firm within a couple of
seconds. Trim the free end so that it is virtually flush with the end of
the reed slot (this will prevent sticking by reducing the contact area
of the valve on the reedplate).

If your tiny spot of glue was tiny enough, it won't spread down the
sides of the slot and the valve should give you trouble-free service.

Brendan
WEB: http://www.brendan-power.com <http://www.brendan-power.com/>