Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum 12 year old Yammy glue failure on 60% of the keys

How many have run across this problem? I never have. Many keytops have fallen off and most of the others are on their way to falling off. The rest of the piano in excellent shape.

Take some pictures and send them to Yamaha. I would think they would like to know about this.

An excellent idea.

Which model of Yamaha? What material are the key tops? Which country of origin? A very unusual situation.

C2, manufactured for US market around 2003.

Technically put of warranty, but they have been known to fix these anyway. Not good for the reputation. Clearly a defect.

Peter Grey Piano Doctor

I think their number is still 800-854-1569.

You could just get some PVC-E glue and put them back on yourself. It's pretty easy.

PVC-E glue is no longer available.

Do you mean the PVC-E glue I buy from supply houses has been discontinued?



Hi Tim

That is the current plan barring Yamaha stepping up to offer "something". And at least for the time being I have enough PVC-E to glue about 1000 keys but I wonder what Ed means about no longer available.

Yamaha had a warranty issue with this. I recovered a number of key sets for them. They will probably still cover replacement.

??
A quick google search seems to indicate it's available from many different sellers.

I read a suggestion, I think it was in the PTG forum, years ago, that PVC-E might be the same as Evacon-R bookbinding adhesive https://store.bookbinding.co.uk/store/product/5130/Eva-con-R-Adhesive-500ml/

Some years ago I obtained some Evacon-R. I've never used it for a whole set of keys, just for little jobs here and there around the house - and for sticking some books together!

I stuck a plastic sharp to a little piece of mahogany and it stuck extremely well, even though the surface area of a plastic sharp is small, as they're hollow. I also stuck a plastic white key covering to a little piece of pine. That stuck too, though not as well as the sharp to mahogany - I was able to pull it off (after a week or two) though it would have stayed on had I not pulled. And I had not 'keyed' the surface of the pine by light sanding; it was very smooth.

I also stuck some little bits of felt to the mahogany, and they stuck well. It does take a while for the Evacon-R to dry. The blurb says it can be thickened with a starch paste, which might be worth doing, as it's pretty runny.

It looks and smells like PVA, but it is chemically different. It retails some flexibility, rather than drying brittle. Which, I guess, is what you need for bookbinding.

Roo-Glue is presently being marketed as a substitute for PVC-E as well.

Peter Grey Piano Doctor

Oh that's interesting. Reading about Roo-GLue, it looks like it would work very well for key coverings.

Titebond seem to have an equivalent, "Melamine Glue" which I guess would work too.

Yes ☺

Peter Grey Piano Doctor

When I switched over from PVC-E to Roo Glue I tested them against each other. Roo Glue outperformed PVC-E.

That's useful to know, Bill; thank you for sharing!

Though, when I think about it, what were the performance criteria?

That was my thought as well.