The strut brackets on the lower wing required re-design to achieve the goal of being able to completely seperate the upper and lower wing panels and allow complete disassembly of the rigging without the need to cut any cables. If one wishes only to remove the existing fabric and replace it, the wing panels are easily seperated and all the rigging is preserved for reassembly using a modified bracket, plastic tubing saddles and AN hardware. If re-rigging is necessary the cable bushings can be more easily salvaged from the old rigging after removing the rigging from the wing panels.
The original design used specially fabricated brackets on the leading edge that allowed the bracket to wrap around the 1.5 inch spar and mate against the 1.0 inch strut without the need for a saddle. This required fabrication of a forming die to produce an indent in the bracket to acheive the correct plane on the bracket surface to mate against the strut surface. The indent angle allows the rivnut barrel to line up as a straight shot for the strut bolt to thread into it. The photos below show how this looks. Notice how the indent stamped into the bracket creates a surface out of plane with the bracket plane.
You can see they are all flat and have both sides cut with 3/16 inch holes vs the kit versions that needed a 0.25 inch hole on one side to accomodate the 0.25 inch rivnut. I am using the original custom brackets at all the quick disconnect locations on the upper wing since I am still using rivnuts there.
The original design used specially fabricated brackets on the leading edge that allowed the bracket to wrap around the 1.5 inch spar and mate against the 1.0 inch strut without the need for a saddle. This required fabrication of a forming die to produce an indent in the bracket to acheive the correct plane on the bracket surface to mate against the strut surface. The indent angle allows the rivnut barrel to line up as a straight shot for the strut bolt to thread into it. The photos below show how this looks. Notice how the indent stamped into the bracket creates a surface out of plane with the bracket plane.
The last photo more clearly shows the installed rivnut mounted in the formed indent such that it matches the plane of the 1.0 inch strut surface once the bracket is wrapped around the 1.5 inch leading edge spar.
The alternative approach I decided to take once I found a source for tubing saddles that add 0.5 inch to the struts allowed me to eliminate the need for this custom tooling which is expensive. The photos below show both leading edge brackets and trailing edge brackets produced by a local shop that does CNC laser cutting from files I generated using DraftSight which is a free CAD application available on the internet. The files can be found on the Yahoo Easy Riser group. The local CNC shop also offered to press in the 1.5 inch finish bend so I didn't need to mess around trying to form the bracket around a mandrel.
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