<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><SPAN class="Apple-tab-span" style="white-space:pre"> </SPAN>Spurlock's sizing cauls for .146" are .227", #1 caul is .185", and final #2 is .149" (at least that's what mine measure. Bill could have changed his specs since I bought mine). This means that there is a total of .081" to make up between sizing and the pin size itself, and a little less to allow for "frictionless" movement. Interestingly there is .042" between sizing and #1, but only .036" between #1 and #2. I'm not sure what Bill had in mind (yes, I know, I should ask him <G>), but suspect he was thinking in terms of .045" or so felt, and that the gap between #1 and #2 would be smaller allowing for the compression of the first layer of felt in the clamping process (the #1 clamp has wood on one side, #2 has felt on both).<DIV><SPAN class="Apple-tab-span" style="white-space:pre"> </SPAN>Me, I use mostly BU-6 and BU-3 from Pianotek, which measure .038 and .043 using my micrometer with its friction brake (.043" only when the mortise is larger than the sizing cauls). I find a very loose fit with the caul gives the best long term results. As I mentioned some time ago, I'd druther have #1 be .190 or so, to hold the felt a little firmer for cutting purposes. And I added a layer or two of scotch tape or other tape to some to experiment, and considered asking Bill to make me up some custom ones. But I get by just fine the way I do it now, so it's a low priority.</DIV><DIV><SPAN class="Apple-tab-span" style="white-space:pre"> </SPAN>Ed, I wonder at your using spring clamps, but saying you don't want heavy clamping pressure. Seems like that's a contradiction, but maybe I don't know what you mean by spring clamps. The cauls only apply pressure to the extent they are wider than the gap between the mortise and the felt size plus a bit of glue. Very little to none in my technique. The caul mostly just holds the felt in place while the glue dries. I have had no problem with felts falling out, so I assume this is all the clamping needed. I also iron all the bushings briefly (1 to 2 seconds tops), which probably helps with "grab" a bit. The short time doesn't allow the glue to become liquid enough to penetrate the cloth much.<BR><DIV> <SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><DIV>Regards,</DIV><DIV>Fred Sturm</DIV><DIV>University of New Mexico</DIV><DIV><A href="mailto:fssturm@unm.edu">fssturm@unm.edu</A></DIV><DIV><BR class="khtml-block-placeholder"></DIV><BR class="Apple-interchange-newline"></SPAN></SPAN> </DIV><BR><DIV><DIV>On Jul 31, 2007, at 9:08 AM, <A href="mailto:A440A@aol.com">A440A@aol.com</A> wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><FONT face="arial,helvetica"><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2">Fred asks, <BR> </FONT><BLOCKQUOTE cite="" style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px" type="CITE"><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2"></FONT><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2">Do you use cauls different from Spurlock's standard sizes? I find they require considerably thinner cloth than .053. <<</FONT><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2"><BR> </FONT></BLOCKQUOTE><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2"></FONT><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2"><BR> For Steinways, I use the stock felt with spring clamps on the balance rail, and, usually, .162" cauls on the fronts. For max. longevity, I try to avoid thick glue and heavy clamping pressure, as I feel that it basically turns the back of the cloth into an inflexible matrix, leaving less actual cloth to absorb the force of keys hitting the pins. <BR> I once mixed up some hide glue, very thick, and began gluing the various felts to wood. I then thinned it down, and glued the same felts. Then, thinner yet. It appeared that the thick glue captured more of the felt when pressure was applied, effectively rendering the "felt" to be thinner while supported by a much thicker glue/felt base. It also made it more difficult to remove. <BR> Since I am now rebuilding actions I did 20-25 years ago here at Vanderbilt, I really enjoy the ease of removing backrail cloth, damper felt, upstop rails, etc. that I glued with thin hide glue so long ago. <BR> hope that helps,<BR> regards, <BR> <BR> <BR> <BR> <BR> <BR> </FONT><BLOCKQUOTE cite="" style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px" type="CITE"><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2"></FONT><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2">About humidity effects, It seems like the felt is a bigger factor, as high humidity yields sluggishness. The idea being that felt will swell, closing the gap, while the gap becomes wider due to expansion of the entire key (or button). I guess if there is crushed wood, though, that would tend to swell in high humidity, also closing the gap (kind of like what I imagine happens with pinblocks and loose pins).<BR> Regards,<BR> <BR> <BR> </FONT></BLOCKQUOTE><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2"></FONT><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2"><BR> <BR> </FONT><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2"><BR> <BR> <BR> <BR> Ed Foote RPT<BR> </FONT><FONT color="#000000" face="Geneva" family="SANSSERIF" size="2"></FONT><BR><BR><BR>**************************************<BR> Get a sneak peek of the all-new AOL at <A href="http://discover.aol.com/memed/aolcom30tour">http://discover.aol.com/memed/aolcom30tour</A></FONT></BLOCKQUOTE></DIV><BR></DIV></BODY></HTML>