Facts and nots : was Recommend Rebuilder?

[Frank Emerson]

> How can they figure out the crown?
> Do they know how much of a compression ridge there is going to be, and
allow 
> for it?
> This seems to me to be impossible.
> Or is there something, I am missing?

They don't figure out the crown.  They let the crown develop and take what
they get.  After the crown "is what it is," they plane the bridge to
achieve the specified down bearing.  Not that I agree with this procedure,
I'm just saying that's how it works for them.

Frank Emerso