Ethan's RV-7

2.6 Hours -

Time constraints only left me with a couple hours to work on the plane today, but my Dad stopped by and helped things move along a little faster than if I was by myself.

We started by placing rivets in the rudder skins and taping them down with rivet tape.  Once all the super-small rivets were taped in place, we flipped the skins over and started to back-rivet the stiffeners on.  After a few rivets, we both had the hang of this.  My Dad would rivet a couple stiffeners, then I would, and so on until all 16 stiffeners were attached.  The back-riveting process was simple, quick, and left a skin with no scratches, dents or other blemishes.

With the stiffeners attached to the skins, we moved on to the rudder skeleton.  The first step was to cleco the R-904 bottom rib to the R-902 spar. Simple.  Next, I had to drill a hole in the rib to 3/8″ using a hole in the spar as the guide.  Again, simple.  Then, we fabricated the R-917 shim.  This was a little harder, but it was just measuring out a rectangle and cutting it from some aluminum sheet.

The complicated part was match drilling the shim.  To do this, we had to line up holes in the rib, spar, shim and the R-405PD rudder horn.  Well, we couldn’t get everything to line up.  After looking at all the parts for 15 minutes, we realized the rudder horn was not allowing the rib to fit flush.  The angle that the horn is constructed from was flat on one edge and rounded on the other.  The flat edge was too high to let the rib slid down to the proper height.  It will need to be rounded to match to other side and, then, all the pieces should nicely fit together.

Rows of rivet tape!

Rivet tape is used to hold all the rivets in place when the piece is flipped over.

My Dad picked up back-riveting quickly.

All the stiffeners are back-riveted to the rudder skin.

Back-riveting is quick, yields good shop heads and a perfectly smooth outer skin.