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Chapter 6-1 CHAPTER SIX REPLACING A STRING Although this course "STRICTLY TUNING" does not offer instruction on piano repair per se, there is one procedure that is necessary to include in any discussion on tuning. That is the replacement of a piano string. No matter how careful you are, and no matter how new a piano may be, it is possible that a string will break during a normal tuning. It is more likely to happen on an older instrument, but just be aware that it can happen any time to anyone. You should know how to make a number of other minor on the spot repairs before you take on your first customer, but for sure, a piano will not make a sound without a string. Numerous other minor repairs are explained on the "BUSINESS" disk which you will receive when you enroll as a student. It is possible that in the beginning stage of your Piano Service Business, you may want to concentrate on tuning and farm out repair work to other technicians in your area. This is not a bad idea for a number of reasons: 1. You will be able to begin advertising and tuning imme- diately upon completing this course. This means $ will be coming in right away. 2. You will be making contacts with other people in this business and as a result will learn a great deal about the prospects in your area. 3. You will not be "pressured" into learning everything about piano servicing before you start tuning. You can take your time with the repair phase take on more and more of this type of work as you are learning. Of course, if you currently are making a living in some other pursuit, I would recommend learning all I have to offer BEFORE you start. This way, when you open your busi- ness your can advertise "TUNING/REPAIR" rather than just restricting yourself to tuning alone. It is beyond the scope of "STRICTLY TUNING" to go into a complete restringing project. We will concentrate our efforts here on single string replacement. First, just as in tuning, you need the necessary tools. When you look through supply house catalogs, you will see there are a great many different shape tools to accomplish the same result. Most of these are excellent so I will not tell you exactly which one you need, just the type of tool necessary. Chapter 6-2 YOU WILL NEED: A wire gauge Tuning hammer ( you should already have) Chain nose or long nose pliers Wire cutters Standard type pliers String lifter String spacer Stringing hook Wire sizes: 12 - 22. Unless you do a great deal of stringing, 1/4 lb. of sizes 12-15 and 1 lb. of the larger sizes will do. BASS STRINGS - see info later in this chapter TREBLE STRING REPLACEMENT Let's assume you are tuning an upright piano and you are just getting into the upper treble - A string BREAKS! Do you break out into a sweat? No - you just calmly recall what I am now going to present. Recall that in the treble, one length of wire actually makes up two strings of a unison. Remove the action by removing the four (or sometimes three) action bracket bolt nuts, removing the wooden rods that are attached to the pedals (trapwork), and lifting the action up and out. Be careful not to damage any dampers on the action bracket bolts. Stand the action in a safe place by leaning it carefully against a solid wall or piece of furniture. Some actions will stand on the action brackets and some won't. Be careful, or you will wish you had al- ready studied the repair section on the Business Disk SEE SPINET ACTION REMOVAL AT END OF CHAPTER! Now you have all the working room you need to replace the string. Follow the broken string to the two tuning pins attached to it. Loosen the pins slightly and pry the coil out of the eye with a screw driver, then lift the coil out with your needle nose pliers. Find a clean part of the string and measure it with your wire gauge. Now, DISCARD the old wire before you get cut. I speak from experience! With a tape measure, determine the distance from the upper tuning pin to the hitch pin. Double it for the dis- tance of the return trip to the other tuning pin. Now, ADD 8 inches for the extra needed for the coils on the pin. Cut this amount of wire from the new coil of the same size as the old string. Turn the tuning pins out three full turns with the tuning hammer to allow for the coil and put one end of the wire under the pressure bar and guide it through the eye of Chapter 6-3 the right hand pin with the stringing hook. If you are working on a grand piano put the string on the left hand pin to keep the new coil out of the way of the second coil. Make sure the wire is all the way through the eye and flush with the other side. Then, while holding the wire firmly with the stringing hook, turn the tuning pin clock- wise with the tuning hammer until you have two and a half turns of wire on the pin. Draw the wire down over the bridge and wrap it around the hitch pin. When you bend it around the hitch pin, pull it as tight as you can and put a good bend in it. Now, bring it up and above the next tuning pin. You now have to cut off all of the excess wire EXCEPT for the amount necessary to allow for the three coils on the tuning pin. The easiest way to measure this is by using the width of your hand. Hold the wire above the pin between your thumb and fingers with your hand extended and cut the wire just above your hand so there will be at least three inches of wire above the pin. Guide the string under the pressure bar and through the eye of the tuning pin. Put two coils on the pin, but no more. You now have to put the string around the pins on the bridge and you have to have enough slack in the string to do this. With the string lifter holding the wire steady, turn the pin about one half turn taking care to make the coils neat and the string not overlapping. Now, return to the other pin and finish putting the three neat coils on it with the help of a screwdriver or the string lifter. Put the final half turn on the other pin and you should have a string that has three neat coils on each pin, is threaded around the correct bridge pins and is ready to be tuned. If the coils are not neat enough, loosen the pin slightly and make adjustments. Use your long nose pliers to push the wire firmly into the eye of the pins. Ensure that the string is firmly against the plate just below the hitch pin. If not, use a screwdriver and a small hammer to tap it flush. Use regular pliers and squeeze the wire just above the hitch pin to help with the stretching process. Bring the new string up over pitch about four C.P.S. Since it will fall down quickly, a return trip will be necessary in a few days to bring it back up to pitch. If a return trip is not possible from some reason, and the wire you replaced happens to be one that provides a string for two different pitches, here is what I sometimes do. Bring the new string up over the pitch about six C.P.S. (on both notes) and then place a mute firmly between the two new strings. You will now have only two strings of the left and right note sounding, but they will be in tune because the muted off strings will not be heard. When you return for your next regular appointment, you merely pull out the Chapter 6-4 mute and tune the string in the usual manner. It will have stretched out by then and you should have no problem with it going below pitch. If the wire is two strings of the same unison, you can still mute off the new wire, but be careful that the mute does not cut off the sound of the one remaining string. Explain to the customer that the sound will be a bit "thin" until you return to remove the mute and tune the string. Also, be sure to explain the extra charge necessary for the return trip. If you are lucky, he/she may understand... SINGLE TREBLE STRINGS Occasionally, you will find a treble string that is not wrapped around a hitch pin. It will have a loop on the bottom and will be placed on the hitch pin in the same manner as the bass strings. If this is the case, you will have to wind a loop on the bottom of the string either by hand or with a LOOPING MACHINE available from the supply house of your choice. If you have a looping machine, the directions that come with it are sufficient. If you have to do it by hand, it gets a little more complicated. Put a medium size nail in a vice with the head up better than 1/4". Wrap about two inches (if the wire size is 12-15 or three inches if the wire is thicker) around the nail. Then starting about 3/8" from the nail, wrap the wire around itself with pliers. Make the wrapping as close and as tight as possible. Cut off any wire you are unable to wrap and leave only a 1/4" stub. If this sounds confusing, just look at one of the bass strings on the piano and this procedure should become clear. After doing this by hand two times, I purchased a looping machine. I'm not saying it is impossible to do by hand, but since you will only have to do this occasionally, you will have to practice the procedure in your shop every so often or it will be awkward to do in the customers home. The looping machine works perfectly every time with very little practice. The choice is yours. BASS STRING REPLACEMENT If a bass string breaks, you have two choices. 1) You can send the broken string to the supply house for an exact duplicate, or 2) You can match the string as closely as possible from a supply of "universal bass strings" you can obtain from a supply house. Sending broken bass strings back for duplicates is the choice if there is no time constraint and the customer agrees. However, usually it is preferable to use one of the universal strings. You just purchase a packet of these Chapter 6-5 strings and carry them to all tunings. The instructions included are easy to follow and if you learned the procedure for putting on a treble string, you will have no trouble in putting on a bass string. LOOSE TUNING PINS It is possible that due to the age of the piano, the tuning pin, after being turned out three turns and then back in, will be too loose to hold the tension of the new string. If the pin is on the verge of being too loose before you begin to replace the broken string, you have two choices. The recommended procedure is to replace the pin with an oversized one. You would need a tuning pin gauge to deter- mine the correct size of the old pin. Usually new pianos are pinned with size 2/0. You can purchase pins up to 7/0 by the dozen from any supply house. It is a good idea to carry pin sizes 3/0, 4/0 and 5/0 with you at all times. The other choice is to take out the old tuning pin and insert a metal tuning pin bushing in the hole. Replace the old pin and you effectively have increased the old tuning pin by two sizes. These bushings are very inexpensive and are an acceptable repair. If you have to go up more than two sizes, you of course would have to use a larger tuning pin. The procedure is to turn out the old pins, determine the size and select new pins at least two sizes larger. Then, using a tuning pin punch (available from the supply house) and a hammer, pound in the new pins until they are level with the other old pins. Now, turn out the new pins three full turns and proceed with the stringing process. CAUTION: If you are working on a grand piano, NEVER pound in the tuning pins without using a jack under the pin block. The jack to use is available from any supply house and an explanation on its use is included. In an upright piano, the pin block is part of the structure of the piano but in the grand, it is an entity all its own and will crack under hard pounding. If you are only replacing a few pins, it is permissible to turn in the pins with the tuning hammer on a grand. However, when completely restringing the grand piano it is better to pound them in. REMOVING THE SPINET ACTION In the 1930's a new type of piano action was introduced called the "Drop Action". It is identical to the other typical upright actions except for: The DROP ACTION or Indirect Blow Action is mostly placed BELOW the key height. A lifter of some sort (usually a wire) is attached to the back of the key and extends down- Chapter 6-6 ward to the bottom of the whippen. When the key is struck, the lifter wire lifts the whippen and from then on, every- thing works just as in the "DIRECT BLOW" action. When removing this type action you must first disengage the lifter wires from the back of the key - attach them to the action rail (with string or tape) - remove the action bolts or screws - remove the screws that hold the bottom of the action to the piano - detach the pedal rods from the action and lift it straight up and out. That is an over simplification of the removal of the SPINET action, but it is essentially correct. The important thing to remember is that you must get the lifter wires out of the way before removal of the action or you will surely break them when lifting it out. It is possible that there will not be enough room to safely lift out the action without removing the keys from the key bed. If you need to remove the keys, be sure to number them from 1 -88 with a pencil before removal. Most manufacturers number the keys on the top, but the numbers may be hard to read. ALSO, be very careful when lifting out the action so you do not damage the dampers on the tuning pins or rods that the action brackets are attached to. Removing the Spinet Action is more or less a common sense procedure, but since there are so many different types of drop actions out there, I have included a more complete discussion of this procedure in the Repair section on the Business disk. You can also request service manuals directly from the manufacturer when in doubt. The information presented in this chapter should be sufficient for the occasional single string replacement. In this chapter, you learned: 1. Tools necessary to replace piano strings 2. Treble string replacement 3. "Single" treble string replacement (how to make a loop in the string) 4. Bass string replacement 5. What to do in case of loose tuning pins 6. Cautions on pounding in grand tuning pins Press P to print out this chapter, or ESC for the menu