Project Update – Wing Supports
The rear endplates on the Stohr are quite large, and with the wings actually being relatively small – only 6.5″ or so in span – there is a lot of unsupported area.
As such, without some stabilization, the rear wing assembly will vibrate back and forth. Originally, to stiffen it up, I made some support cables with some 3/32
sheathed cable, a few metal tabs, and some ferrules, to make a looped assembly. (see pictures in previous log entry)
This was very cost effective, but the loops in the cables tended to “pull” over time,
which meant I had to continually add tension to the assembly by adding or removing washers from the clevis pin down at the bottom. Additionally, heat from the exhaust
melted the cable sheathing, which ultimately looked quite bad.
To get around this problem, I decided to remake the cables using some better, swaged cables from aircraft spruce using their cables order form. Here is the recipe:
- (2) 20.75″ long, 7×7 stainless, uncoated 3/32 cables
- End #1: 3/32 eye end
- End #2: 10-32 threaded stud (thread a clevis on to this to mount to the eyebolt)
- Lower Mount: 10-32 Eye Bolts in the lower wing support
- Upper Mount: 10-32 Easy-Adapt Clevis Rod-Ends
The total solution cost about $100, but the net result is much more adjustable, repeatable, and stable. I can still use AN washers under the clevis heads at both top and
bottom to make gross adjustments as necessary. Looks way better too.