Bill, thank you very much. There were three individuals that responded. You, Don Rose and Joe & Penny Goss. My thanks to all for the help. Gordon Holley -----Original Message----- From: Billbrpt@AOL.COM [SMTP:Billbrpt@AOL.COM] Sent: Monday, July 16, 2001 2:37 PM To: pianotech@ptg.org Subject: Re: Need explanation of terms In a message dated 7/16/01 2:04:23 PM Central Daylight Time, gholley@hi-techhousing.com (Gordon Holley) writes: > Hello List. Over the past months, while reading the posts and exchanges on > the list, I've encountered three terms used in the authors dialog. I've > read through two books 1) Piano Servicing Tuning & Rebuilding, by Arthur > Reblitz, and The Technical Examination, Source Book - PTG, and cannot find > any explanation on the three terms. Will somebody assist in my search: > 1. "Burning In" - used in the explanation of hammers and the shank area. > 2. "Get The String To Render" - I know what render means, but what does > the term render mead in this usage? > 3. I'm happy to answer these questions for you. 1. I believe what you mean is "Burning Hammer Shanks". "Burning in.." is another term. Take "Burning Hammer Shanks" to mean, "heating" hammer shanks. If the wood of a hammer shank has warped from its original orientation, applying heat to it while twisting it in the opposite direction will cause it to take the bend you desire. A violin maker uses the heat from a hot plate to heat the bow while he puts the desired bend in it. This is the same principal. The word "burn" is simply factory jargon but is commonly understood among piano technicians the same way "to burn a CD" means to copy one, according to the kids these days. In the factory, a small alcohol lamp with a candle sized flame is usually present to do this job. The flame is used to heat the shank. It is not necessary to scorch the shank but it sometimes happens. I think this is where the jargon comes from. We've all blown out the small fire we've started at one time or another. Some technicians use a match, some use a barbecue lighter, I just use a common, disposable cigarette lighter for this purpose. "Burn in" is a term used in Finish Touch Up or Repair. A dent or gouge in the finish can be cosmetically filled with colored lacquer that is melted with a special, heated knife called the "burn in knife". The knife is used to spread the soft, melted lacquer into the damaged area. 2. If you simply turn the tuning pin of a string which is low in pitch, you may get it to sound on pitch initially but after a little time or after playing the key forcefully (which is called a "test blow"), you may notice that the pitch has dropped back somewhat. This is because other segments of the string, on the bridge, past the bridge and even those up towards the tuning pin did not settle their differences in tension by turning the tuning pin alone. The kind of hammer technique used, the use of test blows and simply the passage of time will all affect these other string segments. Getting the string to "render" means to get all of these nonspeaking segments of the string to equalize and settle down so that no further change of pitch occurs. The most difficult "rendering" problems occur with new or newly rebuilt pianos with very tight pins or in older pianos with rust or corrosion. 3. I'm a little unsure of what may be meant by "Raking the Hammers" too. I don't believe I've ever heard anyone say or write that. The hammer "rake" is the angle the hammer has in relation to the shank. It may look 90 degrees or perpendicular but it usually will have a small angle off of 90 degrees put in by design. Small vertical pianos have the most hammer rake. One of the design or rebuilding experts may be better able to tell you about this but I believe the rake is put into the hammer to cause it to be at 90 degrees when it meets the string. Otherwise, if the hammer is at 90 degrees to the shank, it will do what is called "over center" when it meets the string. In other words, the hammer will strike the string somewhere past its center point. You may have also heard the term used in confusion with Spacing and Traveling, two other terms that have to do with the alignment of the hammers to the strings. Bill Bremmer RPT Madison, Wisconsin << File: ATT00053.html >>
This PTG archive page provided courtesy of Moy Piano Service, LLC