What I did with a symmetrical wing was to glue two blocks together with Gorilla glue, weight down and let sit overnight.

When I cut the blocks to shape (The outside dimensions of the block itself), the wire did snag at the glue joint, but these were only the straight cuts. You can just go slow and wait for it to cut its way through.

Since the glue joint ran through the centers of the rib templates, the wire never came in contact while cutting the airfoil.

If you want to, you can plan ahead and keep the glue 1/2" or so away from the sizing cuts so the blocks are onlt glued at the wing areas.