<HTML>In a message dated 2/17/2002 7:19:04 PM Pacific Standard Time, mfarrel2@tampabay.rr.com writes: <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">Subj:Rim Bevel Date:2/17/2002 7:19:04 PM Pacific Standard Time From:<A HREF="mailto:mfarrel2@tampabay.rr.com">mfarrel2@tampabay.rr.com</A> Reply-to:<A HREF="mailto:pianotech@ptg.org">pianotech@ptg.org</A> To:<A HREF="mailto:pianotech@ptg.org">pianotech@ptg.org</A> Sent from the Internet Terry you wrote For all you soundboard builders that use tighter arcs than a 60-foot radius: I think the 60-foot radius arc is common on most old pianos (at least the crown was about that when the board was new), and I suppose many newer ones. </BLOCKQUOTE> >>>>>>>>Just when you thought it was safe to think something.......A 60 ft. crown is a starting point for many. I've measured some spots in my boards when glued in and yet unstrung that measured any where from 55 to 70 ft. in the bottom and in  the treble 50 to 25 ft. arcs. I really doubt any new Steinway ever had even one spot that had a sixty ft. crown and I don't think they even had a specification. If they had one I suspect the radius was flatter like 75 to 90 ft. They and other makers dragged a dozen nicely dried boards out of the hot box on a soggy summer  morning and by the time the ribbed the last one in the afternoon the e.m.c.s had changed dramitically. What was that you say specifications? E. m.C. squared = a flat board. Da kno.               And I assume that the edges of a 60-foot radius board will have an angle of about <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">1-1/2 to two degrees at its edges - about the same as the bevel on the inner rim. Now, when you go to 40 or 30-foot radii - or even tighter - surely the edge of the board forms a significantly steeper angle from the horizontal than that of a 60-foot radius board. My understanding is that the bevel of the inner rim is very important to the soundboard maintaining its crown. </BLOCKQUOTE> >>>>>>>>I have installed two of my boards onto  flat rims and those boards (A 6 ft. Weber and a Hardman  5 ft. 10 " and both soft rim pianos) ended up with less crown than any other in my practice. I was a little concened. That was a long time ago and honestly other factors could have entered in. Inexperience? However I see no reason to think that gluing a crowned board to flat surface is a design practice I want to endorse. It would seem that a flat rim introduces another unneeded bending strain. I feel more comfortable gluing the edge of a crowned board to something that's going in the same direction. That being said a beveled rim doesn't seem to inhibit more steeply crowned ribs from retaining their shape.         I agree with Del that once the board is strung it has flattened greatly. Hey you know in that case the board  was probably designed to be jjjjjjjjjust the right hieght when under string load.to match the rim bevel.!!! Who knows. <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px"> So, the question is do you put a steeper angle on the rim bevel, do you angle off the outer 3/4 inches (however wide the inner rim is) of the board to match the existing rim bevel, or do you just clamp the darn thing together and all seems to work just fine.</BLOCKQUOTE> .........>>>>>>>> What you said. works           Just  Fuel for cannon fodder--Dale Erwin          San Diego was great! <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">  </BLOCKQUOTE> </HTML>