pianotech-digest V1997 #1919 (long)

[Ron Nossaman]

>Hi Ron,
>           Your thoughts are correct. Because of the additives, V Pro is
>not Grey Cast Iron but an iron alloy. the additives are for two or three
>reasons. 1. so the melt will flow rapidly without pockets. 2. controls the
>size and amount of free carbon crystals. 3. The alloy will not crack and
>distort with the rapid cooling.

* Thanks, Roger, that's what I thought I'd been reading. 



>Like you I feel unless  you had 6 pianos  will the same scaling 3 with each
>type of plate. we are only guessing at the results. It seems to me that V
>Pro struts and plate thickness is greater that comparable grey cast.  Is it
>not as strong under compression?  the full perimeter design that is in
>favour with vertical V Pro plates tends to make me think so.

* I don't have a clue. Would you, or anyone else, happen to have rough
comparative figures on hardness and tensile strength of the two plate
materials? Not that it would tell me a lot, but it would at least be something.



>More mud to cloud the waters. smile!!???
>Roger

* I'm just looking for some semblance of continuity, is all. Thanks.

 Ron N