Well,... I've never done this job, although I've come across a couple pianos that could use it, but is it as complicated as this makes it appear to be? I thought if I ever had to do it I would just check the location of things before disassembly in case a pelican spring or something should be moved for better response, then take the old board home and make one to match, take it back and install. Or if I did that, would I be in for some nasty surprises? Regards, Clyde Vanderhoofven wrote: > Greetings, > > I recently was called upon to repair an old upright piano that had a large > crack in the bottom board (the board to which the pedals and trapwork are > attached). The bottom board was badly damaged, and needed to be replaced. > I thought it would be useful to have a step-by-step list of procedures to > follow when I need to do this repair. This information may be useful to > you as well. > > ************************************************************************* > > Making a New Bottom Board for an Upright Piano > By David A. Vanderhoofven, RPT > October 16, 2001 > > Purpose: > > The purpose of this procedure is to make a new bottom board for an upright > piano when necessary. The pedals of the piano are attached to the bottom > board, and if this board is cracked, broken or otherwise damaged, the > pedals may not function properly. Also, if this board is damaged (cracked, > stripped out screws, etc.), the pedals may make unwanted excessive noise or > squeaks. This is intended to be a step by step explanation of the process > I used when I recently made a new bottom board for an upright piano. > > Tools and Supplies Needed: > > * Table saw or Skil-Saw > * Jointer > * Biscuit Jointer and biscuits (or doweling jig and wooden dowel pins ) > * 1/2 electric drill and assorted drill bits and driver bits > * Router and assorted router bits > * Palm sander and assorted grits of sandpaper > * Tape measure > * Assorted clamps > * Assorted Phillips and flat blade screw drivers > * Sharpened cabinet scraper or chisel > * Piano Tilter > * Spray can of flat black lacquer > * Spray can of clear gloss lacquer > * An assortment of wood screws > * Wood glue > * Assorted pieces of bushing cloth, felt and leather > * Leather gloves > * Protective Eye glasses > * Respirator face mask > * Shop apron - to protect your clothes > * Vacuum cleaner > * Cleaning cloths > * VJ Lube or Protek MPL > * Pedal Props > * Pedal bushings > * Pinblock plugs > * Wood to make the bottom board > (I used 3/4" thick poplar, but another hardwood or cabinet quality > plywood would also be suitable.) > > Shop Facilities: > > The shop should be well lighted, have enough space so that the technician > can move around comfortably, and must have good ventilation. There must be > no open flames or other sources of a spark that might cause the lacquer > used to burn or explode. A spray booth or other draft free spraying area > is useful. > > Procedure: > > 1. Remove lower front panel, and disengage and remove pedal rods > 2. Lay piano on back using piano tilter > 3. Remove screws holding bottom board in place > 4. Remove bottom board > 5. Measure dimensions of bottom board (thickness, length, width) > 6. Cut new wood to dimensions of old board using table saw or skil saw. > If the old board is wider than the wood you have available, it may be > necessary to glue up several pieces of wood to get the necessary width. If > this is the case, the following steps apply. > A. Use jointer to get smooth edges on wood > B. Use biscuit jointer to cut slots for biscuits (or use electric > drill and dowelling jigs to drill holes for dowels) > C. Apply wood glue to both edges of the wood you are gluing together. > Apply glue to slots and biscuits (or apply glue to dowel holes and dowels) > D. Insert biscuits (or dowels) and clamp edges of boards together > > E. Wipe off excess glue before it dries > F. Allow sufficient period of time for glue to cure (24 hours) > G. Use cabinet scraper or chisel to scrape off excess glue > (Of course, if you use plywood, steps A through G can be omitted) > H. Cut new board to dimensions of old board > I. Sand surface of wood smooth > 7. Use router and router bit on new board to duplicate edge profile of old > board > 8. Spray underside of board with several coats of flat black lacquer, and > spray upper side of board with several coats of clear gloss lacquer. Allow > sufficient time for lacquer to dry. > 9. Repair stripped screw holes in underside of piano - epoxy pinblock > plugs in place. > 10. Replace bushing cloth around each opening in kick board. Replace any > worn bushings in pedal assembly. Polish pedals and clear coat with brass > lacquer if desired. Polish and lubricate pedal pins (replace pedal pins if > necessary). > 11. Position new board in place on underside of piano and clamp in place. > Drill pilot holes for screws to hold board in place. Drill through new > board into bottom of piano using drill bits of correct diameter, and drill > to appropriate depth (use depth stop if necessary. Use a countersink bit > so that screws will be flush with the wood surface. Install several wood > screws to hold bottom board in place. > 12. Locate pedals in correct place and mark screw holes through the pedal > bracket holes. When in proper position, the pedals should not rub on > kickboard on either side, and the pedal horn should not rub on wood of > kickboard. > 13. Remove bottom board and put on workbench. Drill holes for pedal > brackets, and install pedals and brackets. > 14. Install bottom board, making sure to tighten all screws securely > 15. Using piano tilter, return piano to vertical position > 16. locate proper position for trapwork springs, mark and drill holes, > install trapwork and springs with wood screws > 17. Install pedal dowels and regulate pedals. Check for squeaks > 18. Reinstall lower front panel > > Of course, if you have the piano tilted on it's back, this is an ideal time > to take care of any problems with the casters. > > *************************************************************** > > Acknowledgements: > > Thanks to Kevin Way, South West Missouri Player Piano Service, for > excellent help and advice and the use of his jointer and clamps. > > *************************************************************** > > I hope that the above procedure is helpful to you. I am always looking for > a better and more effective way to do things. If you have a correction or > improvement to this procedure, please let me know. All errors are my own. > > Permission is hereby granted to the Piano Technicians Guild to use this > information in any way that will benefit the piano industry. > > Sincerely, > > David A. Vanderhoofven, RPT > Joplin, Missouri > dkvander@joplin.com > > http://www.janics.com/~dkvander/piano.html
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