Here you can see the tension of a 1925 grand piano Pleyel
mod 3 -1925

A high tension scale mounted with a softer wire than Roslau

See how the solicitation lower (but stay accepteable) with modern wire

https://docs.google.com/file/d/0B6GjQDkF_AMQOUhkOG1RNjFjc2c/edit?usp=sharing

Then, a Boesendorfer 190 - year 1915

https://docs.google.com/file/d/0B6GjQDkF_AMQV2JrOWlrZkRrLTg/edit?usp=sharing

less long strings, moderate tension , no correction of the plate breaks on the bridge

Thank you BDB and Olek ! I have SO much to learn !

I will mic the uppermost wound string and apply that equation and respond after work today if I can.

The other question I asked was this:
This is exactly the information I needed to hear ! SO, if I understand correctly, I should make adjustments to my "tweaked" scale, to a "final" scale using even numbers of unisons while still attempting to retain the most even pounds of tension, right ?

I hope that is the correct theory, but any input would be very much welcomed and appreciated!

Thank you ALL for your help !
ncpianoman

OK.... using your wound string conversion, my uppermost wound string is .0575 (57.5 - 5)/2 = 26.250 gauge. With my string length for that note and this 26.25 theoretical guage, the spreadsheet shows 165.148 pounds. The first wire @ #18 shows 162.305 pounds. As I said before, the tension only varies 9 pounds from bottom to top wire (29 - 88).

Does that suggest I am there and ready to string this piano? I think I am to that point, but just wanted your professional opinion.

Again, thanks for sharing the spreadsheet and for all of your advise !

ncpianoman

That looks good. It is hard to get that close on many pianos.

Thank you very much for your help and patience ! I could never have done it without the spreadsheet !

As it turned out, I had to adjust the scale slightly to gain an even number of unisons with each wire size and ended up with a variation of 13.3 pounds from top wire to smallest wound string, but I trust that will suffice.

Once again, thank you to all who assisted me with this learning process !

ncpianoman