Hrs: 5

Side rails

Today’s task was installing the side rails.

First step was installing the M5 nut-plates with 2.4 mm rivets. I didn’t had enough stainless steel rivets and was unable to source 120 degrees countersunk stainless steel 2.4 mm rivets. Masterfix has these rivets in aluminium, which is fine as well because these rivets are only to prevent the nut-plate from spinning:

Two angles of the side rails go into the rear fuselage. The upper holes that share the holes with the stringer were 4.1 mm in the stringer but 3.2 mm in the angle. So these holes had to be enlarged:

Angles are installed and all top holes accept the 4 mm cleco’s. However there is one ghost hole:

The right forward angle had some holes as well that needed to be up-sized to 4.1 mm (the left one was fine):

The orientation of the “side rail joining plate” is not clear, I checked with TAF and this is the correct orientation (identified by the 45 degrees notch on the upper rear side). However one hole is not aligned:

The stack of parts from the outside with the misaligned holes:

The gusset on the inside will conflict with 2 rivets. Like other builders I will have to file a notch in the gusset:

Big question now is “when and what to rivet”? Another builder named this rivet “the impossible rivet”, because when the side rails are in and riveted, access to this hole is obstructed. But I don’t want to close the arc now…

Next I checked if the side rails are parallel to each other. The jigs are all in and the upper firewall bracket is in. However the front is couple of mm narrower:

Overview of current status: