Greg, WOW, what an idea!!! I like the way you think. Any other great "workshop" suggestions from the experienced on this list? Bruce Browning The Piano Tuner. Graham > If you didn't have to worry about hurting the piano, what "stress tests" > would you want to try? > > Have you always wondered how the frame of an upright is joined? > > What does the back of a plate look like? Will it break if you remove the > plate screws under tension? > > > I’m working on ideas for a chapter "Gross Anatomy" dissection of a dead > upright piano. Rather than just pushing it out the second floor window > like they do on YouTube, this would be a serious, planned series of > experiments. We would get to see how pianos are put together, test things > to destruction, take home sample parts, etc. Old hat for rebuilders, > perhaps, but valuable experience for techs who don't usually tear 'em down > that far. > > Heck, even rebuilders may want to "test to destruction" certain components > that they usually need to save. > > I'm hoping you can help me think through the experimental sequence below. > > I have a big old upright, but plan to check with local stores and to see > if they plan on transporting any smaller, perhaps more modern pianos to > the dump. It may as well go to us and save the dumping fee. I will > recycle most of the case parts, action, and plate. Other junk will go in > my dumpster. > > Ideas for "Piano Gross Anatomy" experiments: (Please suggest additional > ideas!) > > 1. Put CA glue on tuning pins that are loose. Check penetration later > when plate is removed. > > 2. Voicing related: > a. Revival of tubby bass string using the twist, loop, > loosen-and-whack methods. > b. Shave hammer shanks in treble to hear tone differences. Test for > shaved-shank breakage on hard blows. > c. Over-file hammers, making them too light, too pointy, too flat, > crooked crown, etc. > d. Over-needle some hammers. Over-lacquer some. Over-steam some. > Iron some. Over-iron some. > > 3. String Termination Tests: > a. Put CA glue on the bridge and listen to false beats. Better? > Worse? How much is too much? > b. Pound in bridge pins. Listen. Pound more. Alot. Too much. > c. Over-seat strings at bridge, intentionally causing damage to > bridge surface. Beats? How much is too much? > d. Downbearing modifications? Shim under strings? Chop away some > of the bridge? > > 4. How far over pitch can old piano strings go before breaking? > a. Test in several octaves. > b. Test using smooth pull vs jerk hammer technique > c. How hard can you press on a string with a pizza-wheel style > string stretcher? How hard can you whack it with a screwdriver at > the v-bar? > d. Try ProLube at bearings to see if it makes any difference > > 5. Structural tests: > a. Jack the soundboard from the back frame and test for pitch > change. How much impact does the rise and fall of the soundboard > have on pitch? > b. Remove sections of soundboard, or ribs, or just separate from rim > to see how tone changes. > c. Remove a couple back posts. > d. Remove several (most? all?) plate screws. > e. Whack the plate with a sledge hammer. > > 6. Dissassembly as if for rebuilding. > a. Remove keyframe, keydesk, legs, toeblocks, bottom board. > b. Break off sides. > c. Remove strings quickly, using becket breaker and/or power drill > motor, and/or metal cutting angle grinder. > d. Remove plate. > e. Test bond of pinblock to frame. > f. Check penetration of CA glue on tuning pins. > > This could easily go on for several meetings, but I think much of it could > be done in one session (short business, long technical) if I pre-prep the > piano. I would remove loose case parts and hardware, remove keyframe > screws, apply lacquer to hammers (so it can dry), steam hammers, apply CA > to pinblock and bridge. Gather tools, cameras. Bring zip-lock baggies > for small parts “party favors†for participants. Prepare follow-up > report for PianoTech list. > > What else? > > Greg Graham > > > >
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