Rear spars (almost) complete! Riveting the rear spars

My rear spars are done! Well, almost.

Before I riveted anything I made sure to dimple the aileron bracket doublers and the holes in the spar flanges that any of the spar doublers would be covering. I maybe could have dimpled these holes later but it would have been difficult with the doublers in the way.

About the only things that I have left to attach to the rear spars are the aileron brackets and the aileron and flap gap braces. Those will come later once I'm done with the rest of the main wing structures, so for now I'm calling the rear spars done!

It's time to move on to everyone's absolute, undisputed favorite part of the wing kit, the wing ribs!

Priming rear spar parts and tiedown brackets

I took care of priming all the parts for the rear spar as well as the tiedown brackets so I could finally finish putting them all together. The rear spars are easily the most cumbersome parts I've had to prime due to their sheer size. I'll need to get creative to prime the wing skins...

Final rear spar work before priming

The areas on the rear spar where the aileron brackets will be mounted have been know to develop cracks on older RV-7 kits, so the newest kits include blank doubler plates that need to be match drilled and riveted to the spars to keep things strong. Probably a good thing.

I did my best to center each plate with its corresponding rivet holes, clamped each plate flush with the spar, then match drilled each one.

The hole where the aileron pushrod goes through the spar of course needs to be cut into the doubler plate to match, lest I try to fly an airplane with no ailerons. I started by tracing the cutout onto the doubler with a sharpie then drilling a #30 hole into the plate as close to the center of the cutout as I could. My plan was to use the step drill to gradually enlarge the hole then use the dremel to finish it off.

At this point the unibit was too big to keep going with it, so I switched to using a dremel tool with a cutoff wheel to remove most of the rest of the material.

It looks messy as heck, but trust me, it gets better!

To finish each cutout I switched the cutoff wheel for a sanding bit to file and smooth the cutout to its final size. The results speak for themselves:

Clean!