You measure the lengths from the inside edge, i.e. so they match the outer
dimension of the surface you're attaching them to. For the bookcase,
measure the width across the front and transfer that to a piece of molding
and cut, making sure of the miters. You then can simply make a few pieces
overlength for the side moldings, miter one end to match either end of the
front molding. Then you fine tune the fit for the front corners, and when
satisfied, mark the rear of the side moldings for trimming flush with the
back of the case.
Mike
<[email protected]> wrote in message
news:[email protected]...
> How do you measure the cut lengths of a crown moulding if you are
> trying to join a compound miter? For instance, what do you measure and
> where would you make the cut to get the front moulding to join with
> the side mouldings of a bookcase top?
> Thanks.