Andy,
The power lam is part of a triple taper lamination. The middle 12" has a .001 taper per inch, 12" on both ends has an .008 taper per inch. Basically it's hourglass shaped.
To make the combo taper I first sanded a .100 thick parallel, then used the combo taper sled to sand it to .050 thick at the mid point(18" from each end).
Starting at the butt end, this is how it looks, the first 6" is .100 parallel, the next 6" tapers from .100 to .056, the middle 12" tapers from .056 to .044, the next 6" tapers from .044 to .100, and the last 6" is .100 parallel.
I measure my stack height in the middle of the lamination(18" form each end). This bow measured .239"
Kenny can sell you some of these laminations if you want to try them.