Chuck Behm wrote: > Ron - I've got a suitable candidate piano (not a customer's) sitting in > the shop right now, needing new keytops. I've got a pint of Schaff's > PVCE sitting on my shelf that I've been meaning to try. I'll give it a > go here as soon as I get a plastic to wood conversion done on a spinet > action which is torn apart on several benches. If there are any > nit-picky type of details concerning your methodology which you would > like me to try, drop me a note, so that I'm recreating your exact > techniques as far as possible. Hi Chuck, Nope, there's nothing picky about it, which is as intentional as I could make it. I like idiot resistance when I can get it, to improve my own chances. In my case, the masking tape holds the top in place and in contact, one across the front (first one on), and two on top. Finger pressure to get a little squeeze out. By the time I have them all taped, I can start at the first one and remove it, but I usually give it an hour. Trim next day. > Have you yourself used contact cement on keytops? Yes, I have, and didn't like it a bit. That's why I switched to PVCE when I found out about it. Actually, I switched to Player Piano Company's #320 "plastic glue", and later to Pianotek's PVCE. The problems I've seen with the adhesion of contact cement applied keytops aren't immediate. They happen one, or two, or five years later as the glue morphs into something else and fails. It may be a matter of using the right stuff, and applying it the right way while keeping it off of the top, but I don't like the long term penalty clause for guessing wrong. I get PVCE from Pianotek, so there's no question of the brand. I know how it ages, which is not detectably as nearly as I can tell. It hangs on like grim death once it's cured for a couple of days, which is plenty strong for me. It doesn't stink. I can get it off of my fingers easily, and off of the key top when I get sloppy. It has a shelf life I can live with, and it's reasonably cheap. As nearly as I can tell, I have the most simple, benign, and dependable method available to me already. The only thing that would make me switch is a superior benefit of another method and material, without losing the benefits of this one. Contact cement doesn't have anything better to offer that I can see other than I save some masking tape at the expense of having to build a few clamps. If contact cement works for you, go in peace. I don't like the smell of the stuff, or the handling and timing, or the likelihood of me getting it somewhere where it'll do damage necessitating changing the top again from a spare set. Longevity is still in question too, as I've seen too many sets of contact and spray adhesive sets fail, while I've never seen a #320 or PVCE applied set with a single long term adhesion problem - ever. This includes kids trying to pull tops off. Having chosen an adhesive based on ease and dependability that meets the mechanical needs of the process, I'm not really interested in working out different methods to accommodate what I consider to be an unpleasant and suspect adhesive. I'd call that a step backward. If something I like better than PVCE comes along, I'll move on again and adopt that. I'll go with whatever offers the best benefit/detriment ratio in immediate process, short term, and long term dependability. Ron N
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