Elevator Front Spar Riveting

I continued with the riveting of the elevators this evening. The next step was to cleco the front spar assemblies into place and rivet them to the rib flanges with blind rivets.

This is followed by riveting the skins to the front spar flanges.

Before starting riveting I set up a leveling jig on the bench top using two square aluminum tubes (in the same manner that I did for the rudder). There was a very slight twist in one of the elevators which was easily corrected by blocking one corner and applying pressure in the opposing direction.

I set the rivets with the pneumatic squeezer along the spar flange but stopped at the outer ribs on both sides (the skin needs to be lifted to set rivets inside the assembly before closing it up).

The rivets that attach the rear spar to the inner ribs were tricky to set due to the tight space and the angle of the rib. The squeezer was challenging but there was no way to get a bucking bar in there either. I ended up using a slightly longer rivet than the 3.5 that is called for as I was unable to get an acceptable to-spec rivet without upsizing it slightly.

Setting the rivets that attach the ribs to the elevator gussets was also challenging as the rivet set is hard to get in there given the angle of the spar. I went carefully with these and all four came out to spec without needing any rework.

Next up is closing the skins up around the control horns and along the inner rib. I set all of these with the squeezer.

The next step will be to rivet the tip ribs into place. For another day..