Bass bridge bearing question

[Richard Moody]

> >    Is 1.5 mm enough or should I go for more?   Is there "theory" or idea
> >that bridges with aprons need less bearing?  ---ric
>
>
> This should be enough. Did you check the bearing on the tenor bridge while
> the strings were still at pitch? If so, you can check it now and see how
> far you can expect the soundboard to deflect when you pull it back up.
That
> will tell you something about what will happen in the bass under load.
> Better yet, pull the rest of the piano to pitch and measure again before
> permanently attaching the bass bridge. If you have any bearing at all,
> you're probably fine.
>
> Just curious, why is the tension down in the rest of the piano?
>
> Ron N

Thanks for the reply.
The tension is down because I wanted to see how much the sound board came
up.   It didn't do much.   Like 1 mm or less.  Checking again 3 months later
I still have the same readings.
    Also I have heard favorable ideas for releasing the tension and letting
the sound board "breathe".  I don't know one way or the other.  Could be
like letting wine breath in a caraffe. How do you really tell?  If it is
really better?  I do know it ain't too stable (in tuning) for the first two
months. Since I haven't heard astounding differences from letting the
tension down,  this alone is making me suspect an exerise in futility.
    With the bass strings "off" I can now take measurements and compute
tension. But what a hassel taking measurements. No wonder Travis didn't do
that.   Maybe I will do a rubbing.   At any rate I will put it into a spread
sheet and offer it to anyone interested.    ---ric