I had purposely left the fwd inboard rib wide so that I didn't have to worry about knife trimming along the edge. This allowed me to let the skin cure, and then trim it perfectly 90 degrees to the shear wall face of the spar.
With the skin trimmed 90 degrees to the shear wall face, it was now time to cut the rib to proper size. So I dug a knife into it and cut away!
Perfectly perpendicular to the shear wall face... looking good!
The plans say to carve out 0.7" into the rib... so using a dremel, I milled away! Pretty messy!
I then used a flat board and sand paper to get a nice smooth, flat surface...
I made a "check tool" to make sure I was 0.7" all around...
I then used the dremel with a sanding wheel at very low speed to prep the rim for a nice glass-to-glass bond...
I then flipped the wing over and prepped the other side of the rim...
With the fwd inboard rib all milled out, it was time to glass it! I stood the wing upright on the worktable... notice how I taped the RG-400 nav cable to the inboard root so it would not get in the way during glassing...
I cut the two 3" x 30" UNI strips and the 3 plies BID for the inboard rib as stated in the plans.
Started off by painting plain epoxy onto the surface...
I placed the center of the UNI strip on top of the metal attach point... I then placed my hand on top of it to hold it in place. With my other hand, I pulled on the end of the uni strip towards the direction of the rabbit ear... this allowed the UNI fibers to position themselves in place without any creases..(I had practiced this the day before on my worktable using UNI scraps)...
I then walked over to the other side and did the same thing...
I then wetted the uni strip out...
I then repeated the process for the second uni strip, but this time going along the opposite rabbit ear...
Backside of UNI strip #2...
Wetted uni strip #2 out...
Notice how the uni strips create a "V" over the pocket... this V is not cut as to eliminate a high-stress concentration point.
Next, it was time to glass the rib. I started out by painting plain epoxy all around the glass rim. I then slurried the foam surface and then applied a small flox fillet to help transition the rib to the rim.
Ready for BID ply #1...
Notice how I also added a flox fillet along the edge where the rib meets the shear wall face...
I position the BID ply onto the surface.. I had plain epoxy with a brush ready and used it to tack it onto the surface...
I made sure there was about 0.7" overlap onto the shear wall face...
Using the brush, I wetted the entire ply out, and made sure to tuck the corners into the flox fillet.. I checked for air bubbles and also made sure the entire glass-to-glass surface was properly wetted out...
I then trimmed the edges to have approx 0.5" overhang...
BID ply #2... same process...
The 3rd BID ply extends over the metal attach bracket at the bottom...
After wetting it out, I peel plied the edges for a nice smooth transition.
The next day, I used a sharpie to draw a line where the rib had to be trimmed...
Using the multitool, I trimmed away... being extremely cautious to not cut the NAV cable!
I then cut the strobe light conduit access hole out using the dremel..
Here is a detailed shot on how I glassed around the nav cable so that it comes out just aft of the leading edge...
There it is... the forward inboard rib is complete!
At this point, I will put the right wing in storage and begin work on the left wing. The aft inboard rib and the aileron will have to wait for now - I figure I can work on them simultaneously after the left wing is complete.
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