In message , TheOldFellow
writes
On Wed, 5 Aug 2009 20:42:09 +0200
"Paul Moore" wrote:

For the piano, I don't know what to do, any ideas?


Whilst there are plenty of things about to put under chairs and tables
to spread the load a bit, a piano is a problem of a different order.
We are talking of a load of about a tonne applied through the brass
wheels - three almost-point-loads. What you have to do is to change
these loads to spread-loads over, say, 100 sq cms (10x10 cms pad) each.
I'd suggest steel plates of that size with 5mm felt stuck to the
underside. How you get the piano to stay on them, I'm not sure - have
a thick washer with a big hole brazed on maybe. This must be a problem
that piano dealers understand, talk to one of them.

Or just use cups for the piano castors:

http://www.pianoaccessoryshop.co.uk/castor-cups-368-0.html
--
Chris French