Or just use a second wand
Edit: ninja'd.
Triple-check that you have the 26 obsidian in place with the 9 slabs on top.
Use the same wand, make sure you're right-clicking on the middle layer of glass(sometimes makes a difference). If you're switching then the node will eat a piece of glass, an equal trade foci can definitely create a jared node. It will still take a while, gotta catch the node between it's eating pulses and there's no way to tell this(not the same as it's visual pulses).