Impossible Vanishing Sliding Bolt Trick

This bolt slides back and forth through this block of wood, but vanishes in the middle. How is this possible In this video I show how I created this trick. I personally haven t seen this done anywhere before and I came up with this idea on my own, though I doubt I m the first to ever make such a thing. This is my second attempt making this trick, and I definitely have not perfected it. Here are some improvements I would recommend if you try to build this yourself: 1. Predrill a very small hole through the center of the block to help with alignment issues later on. 2. Do not predrill the entire large hole, as there may be chipout issues when routing out the channel around the hole if you get too close (that is why I didn t predrill on this one). 3. Drill the channel so the bolt is directed across the grain, as I did with this one. My first prototype had the bolt aligned with the grain, and this lead to chipout issues where the bolt enters and exits the block. 4. Use whatever string you have that has