Does any one remember the 1 drop holds 2000lbs commercial? Didn't they lift a small car? The trick was, according to a physics teacher I had, that the metal surfaces were milled to an exact fit and highly polished so the one drop of glue spread over the max surface area and was so thin, the glue didn't have to bond to itself. Spanning a gap with CA glue is not strong. It becomes brittle after a few years. I think to prevent the wood from shrinking back in a sizing situation it would be great as it has nice wicking properties in comparison to other glues. It also makes sense that the swelling increases the surface area to tighten the pin and doesn't significantly increase the pressure on the pin. Keith R ----- Original Message ----- From: <A440A@aol.com> To: <pianotech@ptg.org> Sent: Tuesday, July 30, 2002 8:09 AM Subject: Re: CA gluing Grand pinblocks & Uprights My take on it > > Joe wrote: > >> On a final note, I personally do not like CA glue for anything other > >> than temporary repair, because I know that it will fail, eventually. > Newton asks: > > >Upon what data or experience do you base that statement? > > I used a bottle of CA on several projects several years ago. A plastic > clock on the wall, a wooden ruler, a pencil holder cup, etc. About a year > ago, the clock fell off the wall. A week later, the handle came off the cup, > and about two or three weeks after that, the ruler broke. > I don't think CA is all that long term, but what I have seen in blocks is > great. I also think that the increased torque in a pinblock comes from > increasing the surface area between the pin and the wood more than "swelling" > the wood. > Regards, > Ed Foote > >
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