I picked up a trident maple last fall, and it's time to start planning the trunk chop. The tree is about 24" tall now, and I'm planning to chop it down to around 10".
Since the top half of the tree is getting chopped, I'm going to experiment with an air layer. The top part of the trunk doesn't have anything impressive for nebari, so I decided to try a tourniquet wire to thicken it up. I first found about about the tourniquet technique from a thread I posted on Bonsai Nut.
Everything I read online says to use copper wire for a tourniquet, but I ended up using 3mm aluminum wire. I think the recommendation for copper is to use a smaller gauge wire while still being strong enough dig into the trunk.