Step 6: Placing the Magnets
Now to place the magnets that will hold the batarang in place when it is opened. Tape the batarang together in its final position, and drill a pilot hold through the part where the backing piece and the pivoting wing overlap. Exact placement of this hole is not critical, just make sure it's not too close to any of the edges. Then widen this hole with the ½” woodborer bit. I used a ½” because my magnets were just a tiny bit smaller than that, but if you use different magnets from me, adapt the hole to fit. Using tape to separate the holes in the wings (so you don’t glue the wings together), glue the magnets in place. I used two per wing. Make sure you align the North/South correctly so that the wing will not repel itself! The magnets won’t take a lot of stress, so I used two part epoxy resin for this job, which also filled the gap around the magnets.