Making Bucks for vacuum forming

The "screw and glue" method is the standard for building a buck. Pattern routing each new piece against the previous is fine if flush cutting bit is long enough and there is not grain running out along the cut. As much as I prefer to avoid MDF, it would have been a better material for this application. Pattern routing each piece of Douglas fir led to tear-out and inconsistencies in the final surface that had to be sanded and patched.