I made this from scap pallet pieces.
Lot’s of problems. My thought was to leave the fence in the same place and move the box from side to side inside the jig to make larger spline cuts. This way I would only have the one cut through the jig.
Not enough support. The box was moving as I cut and I ended up with different size spline cuts that were not square to the box.
I plan on increasing the size of the whole thing, but will need to purchase wood to do this. I still like the idea of leaving the fence in the same place, but this time I’ll add shims to change the size of the spline cuts.
-- I'll get it done when I get a-round-tuit.