Cut-Through Saddles

[Brent Hutto]

Why does a cut-through saddle (like on old Gibsons, et. al.) have to be glued in its slot when a regular "captive" saddle does not? Is the groove in the top of the bridge shallower on those cut-throughs?

Because I have a guitar with a regular, moden "captive" saddle that isn't quite as long as its slot so it could easily move 1/64" or so toward one end or another but under string tension it does not.

[Greg Mirken]

You are exactly right- the slot for the saddle was shallower than a modern short saddle. Since the slot was sawn rather than routed it had to be the same depth all along its length and it would weaken the bridge if it ran out all the way into the wings. In fact through-saddle bridges are prone to cracks developing at the end of the slot.

A gap at the ends of the saddle slot is of no consequence (except cosmetically). It's how the bottom of the saddle seats in the slot that counts.