DBT85":314o0dap said:
.........Just having trouble getting a nice square mating edge with the other board.......
Put the two boards together, edge to edge, and lightly clamp them at the ends (with the clamps under the boards). If the gap is really bad, run a circular saw along the join, re-clamp (lightly) and repeat. Once the gap has gone, plane them up. If the gap isn't too bad, run a hand-saw along the join. These techniques essentially just knock the high points off. You aren't concerned with getting a pair of straight edges, so much as a pair of meeting edges.