Building the wing rib jig

I'm currently building the jig for the wing ribs. It's simply 3/4" MDF with the paper template glued to it. The instructions said to glue the template to lighter MDF (or similar material), then shape it exactly to the drawing, then use that to draw an outline on heavier MDF. That didn't make sense to me, so I just stuck the paper directly on the heavier MDF. Instead of gluing pieces of wood to the jig, I'm using 1/4" x 1" steel pins, as epoxy won't stick to them. I saw this done by another builder and thought it made sense. The pins were expensive (I spent about $25 on them), but I think it's a nice solution. I still need to cut a few small pieces of spar to glue to the jig, but I don't have the 1st wood kit yet. After I attach those to the jig, it will be done, and I can begin to build ribs.

Drilling holes in the MDF to accept the alignment pins.

It was challenging getting the holes drilled perfectly. I had to re-do a couple,
but that shouldn't be a problem.

The drill press is essential for getting the pins perpendicular
to the MDF. A hand drill jig would work, too.

All holes drilled and all pins inserted. Just need to glue on spar fragments.
I'll add screws to them, too. Since the upper wing is swept, but the ribs are
parallel to the slipstream, there needs to be a little wiggle room where the
spars go through all the ribs. This space will be provided by 5-thousandths
and 35-thousandths shims on either side of the spar fragments. That way,
I can't get the pieces of wood too close to the spars when I build a rib.