You'll, In the mid seventies Bösendorfer had a factory policy of not 'rubbing down' the strings with a wheel, since they believed at the time that the practice could introduce falseness. Like Ron N., I have always been against the wheel for similar reasons. Several have mentioned the wisdom of straightening the lay of all wire segments and tightening the beckett (we use a punch to tighten the becketts). However, the friction at the string offset over the bridge is such that without some deflection (rubbing down) of the speaking length, there will remain a lower tension in the back scale segment which will cause the bridge to be slightly pulled forward, to the detriment of tone quality and in particular tuning stability. I have noticed a slight improvement in the tone of freshly strung pianos after rubbing down the speaking length to pull the string over from the back scale. And I have no doubt that the uneven tensions across the various string segments is a significant factor in the typical poor tuning stability of freshly strung pianos. Therefore, we continue to 'rub down' the speaking length (moderately) with a maple hammer shank (Brian Trout suggested this approach also - hello there Brian). The use of a hammer shank ensures that the technician is unlikely to apply too much force when deflecting the speaking length. I agree with Ron N. that heavy rubbing with a wheel is a very effective method of damaging bridge terminations. If the maple shank approach is applied judiciously, the integrity of string terminations will be preserved. Furthermore, the pounding dowel with inserted hammer is another device which I believe should join the stretching wheel on its way to the refuse pile. I see no justification in pounding the hell out of a nicely regulated action as a means of stabilising a subsequent tuning. After all the pounding is, similar to rubbing down with a shank, merely pulling up the tension of the back scale. A light 'rub down' with a maple hammer shank on the speaking length will achieve an identical result without flattening the rollers at the same time. I strongly recommend that you try this procedure as a substitute for pounding. I forbid any of my technicians to use a pounder. The sound board crown will gradually recede as compression set develops. Therefore, as a piano is tuned over time, the back scale tension will fall in response to the gradual sinking of the board unless the speaking length is pounded or rubbed down. I believe that this is the primary reason for unstable tunings when the 'big hitter' comes to town. If the speaking lengths are 'rubbed down' prior to tuning for the 'big hitter', it will surprise you how well the tuning will stand under the strain. I believe therefore, that the speaking lengths should always be rubbed down lightly before tuning for 'big hitters' (the covered strings can be deflected using a felt covered narrow wooden block, just behind the dampers). The concert may not be particularly pleasant to listen to as the piano cries out for help, but at least it will stay in tune. Ron O -- Overs Pianos Sydney Australia ________________________ Web site: http://www.overspianos.com.au Email: mailto:ron@overspianos.com.au ________________________
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