Devizes Piano Workshop
Action & keyboard
Stringing & Soundboard
Regulating & Voicing



Back to Restoration page
Stringing & Soundboard
Older pianos often require new strings and so this is a regular procedure in piano restoration work. Old strings lose their tenacity and ability to be tuned at the correct pitch; the tone becomes lack-lustre, especially if strings are rusty. The condition of the wrest plank, too, plays an important part in this respect. The ravages of time and modern heating conditions often lead to a deterioration of this important part of the piano - in severe cases it is necessary to replace the wrest plank. When re-stringing, new wrest pins are fitted, their size being carefully selected for correct length and hold, once driven into the wrest plank. Thus strings, wrest plank and wrest pins all need to be in good condition, so as to enable an instrument to be maintained at the proper pitch with good tuning stability.
Once the old set of strings has been removed, the iron frame can be taken out, allowing essential repairs to the soundboard - the ‘belly’ of the piano. In many cases, it is necessary to repair splits in a soundboard by letting-in new spruce, the wood that all piano soundboards are made from. The bridges, which transmit the sound of strings to the soundboard, often require repairs as well. The belly bars, fixed to the back of the soundboard, maintain the curvature that is essential to good tone production; these sometimes become loose and need re-fixing. We use spirit varnish for finishing the soundboard and bridges, as this is compatible with the type of varnish used when most older pianos were made.
Before removal of the old bass strings, a 'rubbing' has to be taken of them in order to show the string maker the critical lengths of the copper wrapping, which are peculiar to each individual piano; this, with certain patterns from the old strings, are sent away and the new strings are specially manufactured. The tenor and treble strings are of steel music wire, specially drawn for the piano industry and of very high tensile strength, allowing for the high tensions used in the modern piano - from 160 lbs to 200 lbs typically. We only use the finest quality polished music wire, manufactured in Germany. At first glance, it is easy to assume that all of the steel strings are of the same gauge. These, however, are made up of many different gauges, with diameters ranging from 0.75mm to 1.30mm. In actual fact, the piano industry has its own standard of gauging, called Music Wire Gauge (MWG), the usual gauges used being from 13MWG to 22 MWG with half gauges in between. In most cases, the gauge changes every 4, 6 or 8 notes, with more frequent changes in the tenor.

Home | Restoration | Tuning Service | Other Services | Pipe Organs | Contact Us | Site Map

Copyright 2003 Peter Munro. All Rights Reserved.