At 08:30 AM 20/02/96 -0700, Avery wrote: >on the subject, can someone please tell me the name of the black plastic-like >material that is being used in Kawai's for flanges, etc.? The material you might be thinking of is called "delrin". Among other things, it's used to make the bodies for some 10-speed bike derailleurs. > Could this be the same material that is sometime used in harpsichords for >the plectrum? I have seen it used for harpsichord jack assemblies as well as the plectrums (plectra?). Kawai plastic flanges are made from "ABS Styran" and are usually a tan colour to simulate wood. I've heard more than a few customers recoil from the idea of "plastic parts", but the ABS is of an extremely high quality and does function correctly, and in some cases better than the equivalent wooden ones. You might be interested in this: The Kawai Service Manual I have (which is undated but has an intro by G. Defebaugh and is probably about 15 years old) has some specific instructions on the care of those flanges. In the manual they do not recommend alcohol and water on the centers because of the danger of over-shrinking as well as the deleterious effects of alcohol on the ABS Styran. What they DO recommend is a mixture of 8 parts naptha to one part mineral oil applied directly to the bushings. Another method (they say) is to remove the action from the piano, apply silicone spray (!) to each tight bushing using a plastic extension tube, followed by WD-40 (!!) applied in the same manner. After that, they suggest making a "tent" over the action with newspaper to form a "wind tunnel" and blow hot air from a hair dryer through it for half an hour or more. If it's STILL sluugish, repin with the next size larger pin. They don't mention how to remove all the junk that would now be EVERYWHERE, including the silicone molecules which will now be attached to almost everything in your shop let alone all the action parts! I have run into more than a few Kawai verticals that wouldn't check properly because the back checks and catch leather were too slippery. I wonder if overspray or creep from this silicone treatment has caused this? I won't keep silicone spray (or anything!) in my house, let alone have in in the workshop. Does anyone know if Kawai still recommends this procedure? Also, does anyone know what effects Protek has on the ABS flanges? Is it safe to use? Finally, the black "carbon jack" Kawai uses is made from carbon and polyacetal according to the spec sheet on it. It's a different material from the flanges as the carbon also acts as a lubricant for the jack. > Any help would be appreciated. Is that more than you wanted to know? B-}) John John Musselwhite, RPT Calgary, Alberta Canada musselj@cadvision.com
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