<html> <body> Ping Pong balls??????? Never heard of that before! Avery At 01:42 PM 5/15/05, you wrote: <blockquote type=cite class=cite cite="">Hello Joe,   thanks for your reply.   Yes, I will share the receipe of the yamaha hammer hardener: take 1 liter of aceton, and 4 ping-pong balls (or 50cl with 2 balls, of course). Put it in a bottle of glass until the balls are totally melted in the aceton. Then you just have to put some small quantities of hardener in small bottles with a pipette to carry it in your toolbag. I haven't tested the hardener myself, but I heard the result when the yamaha tech "juiced" the CFIIIS hammers, after the pianist had complained about the lack of brillance in the treble area. BTW, don't forget to only use WHITE TABLE TENNIS BALLS ;-) an orange ball would result an orange hammer, but hey, why not ? ;-)   Concerning your second reply, to me fine regulation pushes the piano to its limits to a certain point, but when you have to deal with a pianist who wants very very bright sound (like Horowitz wanted, for example), what can you do except hardening the hammers before the concert? It's been only 5 years that I am in the profession, and this is the kind of questions I am asking to myself, trying to find answers, if there are answers, though... ! ;-)   Quentin</blockquote></body> </html>