The fuselage quickbuild kit comes from Van’s with only two 5/8″ ID holes for cable/wire runs over the main spars. This was probably okay 10 years ago when steam gauges still ruled, but my intention is for a nearly all glass cockpit with a dual battery, dual alternator system for maximum reliability on the electrical system. This means running way more wires between the instrument panel / firewall and the batteries located behind the baggage bulkhead.
As a result, I will be adding two additional holes in the spar brackets and will need to reinforce these holes with .063 backing plates custom fabricated for the task.
Notice the top left hole – this is actually the lower of the two factory provided holes. It will be used as the starting point for the two new holes which will be drilled lower on the spar brackets. The rear bracket is 2.25″ wide, the forward bracket is 2.0″ wide. Not sure why, but that’s the way they are.
Here are the rear bracket plates (left and right) after the new holes have been drilled. The reinforcing rivet pattern and spacing was derived from sketches in the AC43-13 document.
Two different views of the spar brackets after being match drilled with the plates. Next steps are alodine and prime the backing plates before riveting in position.