That's really interesting, Louis. Tim
Sent from my iPhone On May 18, 2012, at 3:43 PM, "Louis Aull" <aul...@comcast.net> wrote: > > ------=_NextPart_001_000B_01CD350C.F4FEEE80 > Content-Type: text/plain; > charset="us-ascii" > Content-Transfer-Encoding: 7bit > > Bill, > > > > A lute rib tapers at each end, which means the outer fibers that would have > made it down to the fastening point on each end are cut. As a result, there > is no circular binding force to hold them down like the center fibers of the > rib have. As the wood naturally tries to straighten out of its bend, the > scallop occurs since there is nothing to stop the outer fibers from > straightening. To enhance this naturally, don't bend the rib completely to > the form, and use some force to pull the rib onto the form to complete the > curve. The edges will curl up away from the form more. To defeat this, over > bend and heat twice so the rib is over curved, and the scallop will lay flat > when forced onto the form. Cut the rib roughly to shape before bending . > Another trick is to fasten the rib at each end on the form and use a heat > gun on the outer edges of the rib. The heat will cause the bent curve on the > outer portions to relax and the rib will curl up more. All these methods > produce a mild scallop. It helps to bend all the ribs before installing them > so they are consistent and will meet up on the form. For a brutal scallop, > you would need a shaped forming iron to force the complex curve (yuk). The > thinner the rib, the more the scallop. However, get too thin and you risk > plastic deformation of the shell at the neck block, and the neck will come > forward, ruining the action. > > > > I use aircraft silk on the back of rib joints and have never had one crack. > I can actually heat the inside of the shell before putting on the soundboard > to relax out any stress in the shell. This also enhances the scallop. > > > > I have seen lutes (60's and 70's) where the maker made the ribs thick and > scraped the scallop out. > > > > Louis Aull > > Phone: 770.978.1872 > > Fax: 866.496.4294 > > Cell:404.932.1614 > > LOGO3 > > > > > ------=_NextPart_001_000B_01CD350C.F4FEEE80 > Content-Type: text/html; > charset="us-ascii" > Content-Transfer-Encoding: quoted-printable > > <html xmlns:v="urn:schemas-microsoft-com:vml" > xmlns:o="urn:schemas-microsoft-com:office:office" > xmlns:w="urn:schemas-microsoft-com:office:word" > xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" > xmlns="http://www.w3.org/TR/REC-html40"> > > <head> > <meta http-equiv=Content-Type content="text/html; charset=us-ascii"> > <meta name=Generator content="Microsoft Word 12 (filtered medium)"> > <!--[if !mso]> > <style> > v\:* {behavior:url(#default#VML);} > o\:* {behavior:url(#default#VML);} > w\:* {behavior:url(#default#VML);} > .shape {behavior:url(#default#VML);} > </style> > <![endif]--> > <style> > <!-- > /* Font Definitions */ > @font-face > {font-family:"Cambria Math"; > panose-1:2 4 5 3 5 4 6 3 2 4;} > @font-face > {font-family:Calibri; > panose-1:2 15 5 2 2 2 4 3 2 4;} > @font-face > {font-family:Tahoma; > panose-1:2 11 6 4 3 5 4 4 2 4;} > /* Style Definitions */ > p.MsoNormal, li.MsoNormal, div.MsoNormal > {margin:0in; > margin-bottom:.0001pt; > font-size:11.0pt; > font-family:"Calibri","sans-serif";} > a:link, span.MsoHyperlink > {mso-style-priority:99; > color:blue; > text-decoration:underline;} > a:visited, span.MsoHyperlinkFollowed > {mso-style-priority:99; > color:purple; > text-decoration:underline;} > p.MsoAcetate, li.MsoAcetate, div.MsoAcetate > {mso-style-priority:99; > mso-style-link:"Balloon Text Char"; > margin:0in; > margin-bottom:.0001pt; > font-size:8.0pt; > font-family:"Tahoma","sans-serif";} > span.EmailStyle17 > {mso-style-type:personal-compose; > font-family:"Calibri","sans-serif"; > color:windowtext;} > span.BalloonTextChar > {mso-style-name:"Balloon Text Char"; > mso-style-priority:99; > mso-style-link:"Balloon Text"; > font-family:"Tahoma","sans-serif";} > .MsoChpDefault > {mso-style-type:export-only;} > @page Section1 > {size:8.5in 11.0in; > margin:1.0in 1.0in 1.0in 1.0in;} > div.Section1 > {page:Section1;} > --> > </style> > <!--[if gte mso 9]><xml> > <o:shapedefaults v:ext="edit" spidmax="2050" /> > </xml><![endif]--><!--[if gte mso 9]><xml> > <o:shapelayout v:ext="edit"> > <o:idmap v:ext="edit" data="1" /> > </o:shapelayout></xml><![endif]--> > </head> > > <body lang=EN-US link=blue vlink=purple> > > <div class=Section1> > > <p class=MsoNormal>Bill,<o:p></o:p></p> > > <p class=MsoNormal><o:p> </o:p></p> > > <p class=MsoNormal>A lute rib tapers at each end, which means the outer fibers > that would have made it down to the fastening point on each end are cut. As a > result, there is no circular binding force to hold them down like the center > fibers > of the rib have. As the wood naturally tries to straighten out of its bend, > the > scallop occurs since there is nothing to stop the outer fibers from > straightening. To enhance this naturally, don’t bend the rib completely > to the form, and use some force to pull the rib onto the form to complete the > curve. > The edges will curl up away from the form more. To defeat this, over bend and > heat twice so the rib is over curved, and the scallop will lay flat when > forced > onto the form. Cut the rib roughly to shape before bending . Another trick is > to fasten the rib at each end on the form and use a heat gun on the outer > edges > of the rib. The heat will cause the bent curve on the outer portions to relax > and the rib will curl up more. All these methods produce a mild scallop. It > helps to bend all the ribs before installing them so they are consistent and > will meet up on the form. For a brutal scallop, you would need a shaped > forming > iron to force the complex curve (yuk). The thinner the rib, the more the > scallop. However, get too thin and you risk plastic deformation of the shell > at > the neck block, and the neck will come forward, ruining the > action.<o:p></o:p></p> > > <p class=MsoNormal><o:p> </o:p></p> > > <p class=MsoNormal>I use aircraft silk on the back of rib joints and have > never > had one crack. I can actually heat the inside of the shell before putting on > the soundboard to relax out any stress in the shell. This also enhances the > scallop.<o:p></o:p></p> > > <p class=MsoNormal><o:p> </o:p></p> > > <p class=MsoNormal>I have seen lutes (60’s and 70’s) where the > maker made the ribs thick and scraped the scallop out.<o:p></o:p></p> > > <p class=MsoNormal><o:p> </o:p></p> > > <p class=MsoNormal><span > style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Louis > Aull<o:p></o:p></span></p> > > <p class=MsoNormal><span > style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Phone: > 770.978.1872</span><o:p></o:p></p> > > <p class=MsoNormal><span > style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Fax: > 866.496.4294<o:p></o:p></span></p> > > <p class=MsoNormal><span > style='font-size:10.0pt;font-family:"Arial","sans-serif"'>Cell:404.932.1614 > </span><o:p></o:p></p> > > <p class=MsoNormal><span > style='font-size:10.0pt;font-family:"Arial","sans-serif"'><img > width=75 height=65 id="Picture_x0020_1" > src="cid:image001.gif@01CD3508.EBB3EBE0" > alt=LOGO3><o:p></o:p></span></p> > > <p class=MsoNormal><o:p> </o:p></p> > > </div> > > </body> > > </html> > > ------=_NextPart_001_000B_01CD350C.F4FEEE80-- > > -- > > To get on or off this list see list information at > http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html