The Katie Jig (model #KJ1-12000001) is the only clamp-on jig with true variable spacing. However, the movable finger assemblies require a bit more setup than the fixed models, partly because there is play in the finger assemblies when loosened. To align them correctly, push each one against the mounting bar when securing it.

I found this jig easier to use upright, with a handheld router. There are optional handles available for controlling the jig on a router table, but they are too close to the clamp handles, and the one interferes with the other. Also, due to the variable spacing, the backer board gets eaten away more quickly than similar models, and tearout becomes a problem.

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