I think a bit lite also,my 64" med. d/r is 1.5" at fades with 18" riser and .003" total taper ,it takes .360 to make 50#
You are using thick glass tho,which may increase #s just a bit.
Is the 1st bow off the same form?
I'll let Marty give the stack,his bows are closer to that than mine...