Scott,
I'm nearly done with my first round of 49. I bought 2 2x8x10s. Cut one to all 19" pieces, then cut one 19" piece off the second. The remainder of the second to all 9 1/8" for deep. This is my first stab at this, so I expect it will take a little longer... But I'm curious as to how long, either per frame or per ~50. I'm thinking that by time I'm done, it will average about 3.6 minutes/frame. But I'm not entirely sure, yet.