I could give one reason why Filisko guys don't use screws except on
certain models they build.
It is assumed that an air tight reed plate will give you a more
responsive harp. This may be true to some extent with stock harps.
I trained with the Filisko Guild for 5 years. The amount of effort
they put into tweaking reeds makes the airtight issue null. They
aren't screwing anyone over by
not using screws (except for the cover plates). They add only what
is needed no more no less. If you want screws ,ask. I know they have
some pro customers that want their wood body harps to look as stock
as possible on stage and TV so they nail the coverplates back on
rather then use screws.
It isn't in the customizers or mfg's mind. how can I make this
harmonica user serviceable. Only a small fraction of us know what we
are doing when we take our harps apart and even smaller amount how to
put them together properly. If you worked on as many harps as
customizers, independent repair techs or factory techs have, the
nail issue isn't really an issue.
Take them apart right and they should reassemble right. Bend the
reed plates when you take them off and there is a good chance the
nails will be blamed when you put it together.
mike