This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment Thanks Ron. I seem to remember we went around on this one last time. = This one is a good 1/4-inch gap, and the last tooner supposedly pulled = it up to pitch, tooned it, and squirted a bead of silicone bathroom = caulk into the top of the crack to prevent further spreading (or maybe = he squirted the silicone in the crack before pulling up to pitch - I = wonder which is the proper sequence?). In this case, I will lower pitch first, as with the gap closed, the = piano may go well above A440 (although I must admit I would do that = anyway just for comfort - but in this case I have reason to believe the = piano may have been at A440 after significant pinblock movement had = occurred). I will also use epoxy in the crack. Titebond requires a = clean, well-mated surface and good clamping pressure for a good bond. = Whereas the mating surface in a case like this will likely re-align, = between the debris (silicone glue, drill shavings, whatever else crud) = and the original glue between the pinblock back and back assembly, I = will simply rest much more comfortably at night if I use epoxy. The = couple times I have done this repair, it seemed impossible to get the = crack completely closed - all the more reason to consider use of an = adhesive designed for gap-filling. I do understand that the repair would = likely be successful with the through bolts alone - but overkill is my = middle name - and I think that, arguably, epoxy use in this case may not = really be overkill. Also, this is a relatively new piano - I would feel = more comfortable with an adhesive other than epoxy if the piano were a = 1952 Winter spinet - this is a 15 year old otherwise very good condition = Baldwin console - the piano has the potential for decades of good = service. And yes epoxy use does take a bit more time and requires two = appointments. So the cost is more that a one-appointment repair. I have = little doubt a Titebond repair will work. But I think for some anyway, = there is a different comfort factor. There will always be significant = unknowns regarding the integrity of a repair such as this where the = assembly is not being completely disassembled, resurfaced and re-bonded. Or, I could take the approach a dealer that I am aware of takes on a = several year old expensive vertical piano - no clamps, no through-bolts, = no Tightbond in crack, no epoxy - none of that stuff - just rout out a = little groove along the jagged crack and shim in a shallow piece of = maple, plane down to original height, touch-up finish and waaaallllla - = problem solved (oh, and stack heavy objects on lid of used "repaired" = piano while it resides in the new piano sales showroom, with the new = piano price tag hanging from it, so that nobody is tempted to open the = lid)! Anyway, just a few longwinded, mostly constructive, thoughts on the = subject. Terry Farrell ----- Original Message -----=20 From: "Ron Nossaman" <RNossaman@cox.net> To: "Pianotech" <pianotech@ptg.org> Sent: Thursday, October 02, 2003 11:17 PM Subject: Re: Pinblock Separation Questions >=20 > >Also, any non-bionic technician willing to share how many hours they = have=20 > >taken to do a repair like this - start to finish, not including pitch = > >adjustments and tuning (just clamping, drilling, bonding, bolting and = cleanup)? > > > >Thanks. >=20 > I'm old and fat, so I assume I qualify as non-bionic. I take off the = lid=20 > and put a couple of monster clamps across the top of the back, drawing = the=20 > gap in a bit. If I can close the gap, the clamps will hold it while I = take=20 > out plate screws, drill through holes (3/8"), and install carriage = bolts=20 > from the back. I use washers that will fit around the square shank at = the=20 > head of the bolt to get a bigger footprint than the head provides. You = can=20 > sink a 3/8 carriage bolt pretty deep into a piece of poplar otherwise. = > After the holes are drilled and I have bolts in place and have = vacuumed up,=20 > I loosen the clamps enough to pour Titebond into the crack, helping it = as=20 > necessary with a thin steel spatula purchased for just this sort of = thing.=20 > Glue in, I crank the nuts (lock washer underneath) tight and use the = bolts=20 > to pull the crack(s) together. Trim the bolts with a hacksaw, mop up = the=20 > glue, pack up the tools, take them to truck, bring back my tuning = case, put=20 > the lid back on, pitch adjust and tune the piano. I haven't lowered = the=20 > pitch to bolt the back, so the thing is often not far off, and I don't = have=20 > coils and such to mess with. >=20 > Takes somewhere between an hour and an hour an a half for the repair, = plus=20 > whatever the tuning takes, and I'm done in one trip in usually around = 2.5-3=20 > hours total. >=20 > No failures yet, that I know of. >=20 > Ron N >=20 > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives > ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/29/1c/7e/04/attachment.htm ---------------------- multipart/alternative attachment--
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