piano in window

[L. Davidson Lamoreaux]

RE: Wim Blees question on UV coatings.

 I mentioned the question on UV coatings to the premier piano refinisher here in
the Wash. DC area, Kevin Hancock and it turned out he was involved in finding
info on the same topic. Here is his response to me.

"    I have been a piano refinisher for 20 years. I have done some
investigating into these window coatings for a number of my clients. I have
also consulted Michael Dresdner (finishing Authur and consultant) about these
products.

    UV is the major cause of color fading and deterioration. Reducing it by
nearly 99% will protect the wood from fading.  The films can also reduce the
solar heat gain by as much as 76%.  Many films have very different levels of
protection.  Check with the manufacturer for specifications. Also many window
manufacturers have glass with this protection built into the their products.

    If this condition is expected before the piano gets refinished, an
experienced finisher can add UV blockers and a  HALS (Hindered Amine Light
Stablizer) to further protect the piano

     These products do wear out in time.  Many last as much as 20 years."

Although there has already been extensive discussion on this subject, I thought
that this might still be useful to some.  David Lamoreaux