<!doctype html public "-//W3C//DTD W3 HTML//EN"> <html><head><style type="text/css"></style><title>RE: Vellum Hinges</title></head><body> <div>At 9:54 am -0500 19/2/07, Ed Sutton wrote:</div> <div><br></div> <blockquote type="cite" cite>Further elaboration of your techniques would be of interest to a small number of subscribers to this list.<br> </blockquote> <blockquote type="cite" cite>Can you explain what is a vellum saw?  What kind of glue do you use?  What do you do when the hinge is in the middle of a long strip of hinges?  Do you only repair full sets, or do you sometimes replace single hinges?</blockquote> <blockquote type="cite" cite><br></blockquote> <blockquote type="cite" cite>On Feb 17, 2007 6:52 PM From: Kerry Cooper wrote:</blockquote> <blockquote type="cite" cite><br> <blockquote type="cite" cite>I would not put the damper fingers in water to remove the vellum. This</blockquote> <blockquote type="cite" cite>swells the finger and can also make the abstract twist when drying. Use a</blockquote> <blockquote type="cite" cite>vellum saw to cut out the old vellum, it follows the old vellum if you are</blockquote> <blockquote type="cite" cite>careful.</blockquote> </blockquote> <div><br></div> <div>I have seen many repairs done with a vellum saw and without exception they have been disastrous.  The pictures below show a damper body with the vellum removed using water.  I challenge anyone in the world to achieve such a clean result using a saw, let alone do it successfully 68 times.  Vellum is much tougher than  wood.</div> <div><br></div> <div align="center"><img src="cid:p06240804c1ff7e172c1e@[10.0.0.1].1.0"> <img src="cid:p06240804c1ff7e172c1e@[10.0.0.1].1.1"></div> <div align="center"><br></div> <div>Besides that it is far quicker. It takes about 1 minute per damper to achieve a perfectly clean kerf.  The wood (maple in the case of the Blüthner) is in conact with water for 30 seconds and is thoroughly wiped dry once the vellum is out and the kerf free of glue.  With such a short and superficial exposure to humidity there is no possibility of warping.</div> <div align="center"><br></div> <blockquote type="cite" cite> <blockquote type="cite" cite>To find a replacement vellum, I use old drum skins, as these are of the</blockquote> <blockquote type="cite" cite>thickness needed to do the job, normally around 0.15 mm. I have replace many</blockquote> <blockquote type="cite" cite>sets of these hinges with great success.</blockquote> </blockquote> <div><br></div> <div>I have now completed the work of removing all the Blüthner dampers, most of the hinges being intact.  The thickness of the kerf is 0.5 mm. and the thickness of the original vellum used (thoroughly cleaned of glue) is fairly uniform at 0.4 mm. with a few slightly thinner, the thinnest being 0.35 mm.</div> <div><br></div> <div>I would like to see some close-up photographs of this job done with a saw, together with the time-sheet.</div> <div><br></div> <div>JD</div> <div><br></div> <div><br></div> <div><br></div> <div><br></div> </body> </html>