Riveted Horizontal Stabilizer Rear Spar

Today I was able to finish riveting the HS skins to the ribs, then rivet the rear spar to the ribs. This took longer than I planned, because of a couple of issues.

As I squeezed the rivets around the edges of the skin, I found one side of one of the the in-spar ribs which I had forgotten to dimple. Lucky it was the inboard rib, and I was able to squeeze-dimple the holes using my pneumatic squeezer. I ended up drilling out a rivet in the process, which wastes some time.

The second issue was that a few of my countersink holes on the spar flange were not quite deep enough. This was creating a gap between the skin and the spar, and needed to be addressed. I experimented with some scrap material and switched my countersink cage. The cage that I was using had some slop in it, and was unpredictable. My other cage is a different design and is much better. I increased the depth of a number of holes, then primed the newly cut holes.

Here’s one side done:

Riveting the skins to ribs:

View of the shop heads. Most of my rivets set perfectly, none were in need of replacement:

Rear spar in position and clecoed to ribs and skin:

Pop rivets set, binding the rear spar to the in-spar ribs:

The inboard and outboard ribs get Universal head rivets, which I will probably squeeze. Then the spar flange will get riveted to the skin, and it will be done!