Plate and Rim (was Re: Tension Resonator)

[Richard Brekne]

Delwin D Fandrich wrote:

> Phil,
> .................
> Among the primary functions of the plate are (first) to support string
> tension and (second) to establish and maintain a desired relationship
> between the string plane and the soundboard/bridge assembly. If nothing was
> changing or shifting my #10 wood screws might well be adequate. But even the
> most well-designed rim assembly is going to shift and twist with changes in
> relative humidity--at least they will as long as they are made of wood. If
> the rim is able to do this independently of the plate there will be changes
> in the string plane to bridge/soundboard relationship that will result in
> tuning instability. If the plate is fastened to the rim such that the two
> essentially form an integral whole these changes in relationship will be
> minimized and tuning stability will be improved.
>

Hmmm... a couple questions here if I may...  If the plate is fastened to the rim
in this way (that they form an integral whole), why is the load transfer to the
rim next to nothing or at best insignficant ? And in the perspective of the
discussion a while back on plate compression, why if the plate is thus affected
is the rim basically unaffected ?

Or am I mixing my P's and Ø's again ?

Richard Brekne
RPT, N.P.T.F.
Bergen, Norway
mailto:rbrekne@broadpark.no
http://home.broadpark.no/~rbrekne/ricmain.html