Hi Ted, and others. I just had a long discussion on the phone with a prominent rebuilder I know stateside who had a completely different take on all this. For the first he discounts immediately the problem of sound transmission through glues like Titebond. He points out that the wave lengths of frequencies transmitted are simply far to long to be affected by the difference in hardness between a so called natural glue and a glue like Titebond. And as to creep... he is of the opinion that the glue SHOULD allow for a bit of creep back and forth. The soundboard splitting problem you cite below may be an example where his logic makes sense. If the glue gives in shear direction a bit back and forth, then effectively it works as a kind of shear stress buffer, allowing the soundboard to expand and contract a bit more on the ribs then a glue with more shear holding strength. As to usages such as hanging hammers on shanks. I've always used a Titebond like glue for this job myself. I brush the inside surface of the hole in the hammer first and let that soak a few seconds while I brush on a bit of glue on the shank. Getting a nice sized collar has never been a problem. I've never encountered a real problem removing hammers glued with this kind of glue either. YMMV. Bushing however.... Well... tight bond is just plain too much a pain in the patootey to get out of the mortice... different situation entirely. Fish glue or something similar is just the thing... especially in a University setting where bushings can need changing every couple years on some instruments. Cheers RicB I read somewhere that all glues will creep to a greater or lesser degree. When I was teaching at George Brown College, it was impractical to have a large number of glue pots for hammer gluing, much as I would have preferred hide glue, so we used Titebond. It was much harder to extract hammers from the shanks with this than those glued with hide glue, though ten minutes with a heat gun let them be pulled off readily.The soundboard splits we commonly encounter in old pianos are mostly not true splits at all, but are separated joins, thus showing that creep has occured by shearing at the ribs. It can be assumed that most of these soundbards were glued with hide glue. It is just as well. as if the joints hold, there would be true splits, which would be very difficult to shim unless the grain is very straight. I enjoy working with hide glue, but it is more demanding. It must be carefully controlled in viscosity, though this is also an asset; large work such as cabinetry (and soundboards) should be heated, clamps prepared ahead of assembly and applied very quickly.I have taken to using fish glue for key re-bushing;, but found it necessary to prime coat the mortices first with a 50-50% dilute with water. It is slow setting, but will take hold quickly. Fish glue is easily reversible with the usual mix of warm water and a little wallpaper remover. It is availabele from Veritas. There is a small bottle with a brush in the lid which is ideal for light field repairs, and refill 17oz. bottles. I have seen failures with hide glue through lack of understanding. One new grand I saw had a large number of loose hammerheads. The glue collars were all near black, indicating the glue had been boiled. Hide glue must not be heated above 150F. 140F to 145F is considered the proper range. Bill Spurlock recommends the use of a Rival Express Hot Pot and setting its temperature with the aid of a candy thermometer. I saw these recently in Wal-Mart, and think it a great idea. They cost around $15 compared to $100 or so for a dedicated glue pot. Ted Sambell
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