---------------------- multipart/alternative attachment In a message dated 10/6/03 8:47:52 AM, mfarrel2@tampabay.rr.com writes: >=20 > You want to measure the angular relationship of the string in three areas:= =20 > along the speaking length; along the bridge top; and along the backscale j= ust=20 > aft of the rear bridge pin. Those measurements will give you all the data=20= you=20 > need to characterize downbearing. >=20 > =A0 >=20 > Be aware that all these references to setting bearing to "the thickness o= f=20 > a nickel" or whatever level above some reference point may be fine and dan= dy,=20 > but are completely dependent on the length of the backscale. As the=20 > backscale length between two systems where this type of measurement is bei= ng used=20 > varies, inaccuracies in the reference thickness will be introduced. >=20 > =A0 >=20 > How much downbearing is desirable will depend on the soundboard assembly=20 > design, where you are in the scale, and a host of other factors I know ver= y=20 > little about! >=20 > =A0 >=20 > Terry Farrell >=20 >=20 I really like that term backscale. If I remember S&S threads a fiber line on= =20 the plate, shims it up with various thickness metal slips, then sawcuts the=20 cap to clear this line. This means the bridge cap plane is so many thou abov= e=20 the string plane. This assumes bridge cap is parallel to board and board is=20= some=20 kind of smooth curve and not dimpled down. If you wanted to measure actual=20 angles for the angular relationship, you could but it ain't easy, and I also= =20 don't know factors are involved in setting good down bearings, but I'd like=20= to=20 know ! ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/68/54/29/17/attachment.htm ---------------------- multipart/alternative attachment--
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