Cozy
Chapter 14 - Centersection Spar
The Plan
In this chapter we will build the center section box spar, which joins the wings to the fuselage. You start by building a jig, onto which you assemble 3 sides. It is glassed on the inside and bulkheads and hardpoints are installed. The spar is the closed in, removed from the jig, contoured for the correct shape and metal inserts are installed for hardpoints. then it is glassed and the spar layups are installed.
Would you believe I took pictures!!! Here the spar is jigged , the 3 sides have been made and glassed, and the 4th side is being installed.
Here, as you can see, I couldn't wait! I place the canard and spar in place to get a feel of how it was coming together. This helps psyche me up a little more seeing it coming together.
I'm getting it ready for the shear web. This ties the 2 caps into an "I-beam" arrangement.
Both spar caps are installed and the outside is being glassed. Next hardpoints will be installed and reinforced. Access holes will be cut in the box to allow the wing attachment etc.
OK, so this is where it became evident that I was spending to much time online and not enough building! Sorry guys and gals. I deliberately tried to spend more time with the plane. At this point you have the major stuff done and what you do doesn't let you feel like you are making progress. Especially when you have the spar installed and realize you messed it up BIG TIME. When I was drawing the water lines on the spar it became obvious what I had done. The plans only mention which side of the spar is the top when you are building the jig. I didn't want to get it wrong so I marked the spar when I was removing it from the jig. Only I marked it wrong. So when I installed the spar onto the airframe, the top was on the bottom. Which would have given me anhedral wings and fuel tanks that would not drain in toward the fuselage. I called Marc, and he recomended I remove it ans dtart over;-(. It took about 2 months to build, and 2 weeks to install, and 20 minutes to cut it out. All that work GONE. I had even given away my jig! The good part is that it takes a whole lot less time to build the second one!
The other problem was that the wings were complete AND match drilled to the old spar. The bushings were installed and complete. So how do I go about properly aligning the new spar bushings? I came up with a possible solution. I inserted this adapter into the wing bushings and used it to align the drill for the 1/4 inch starter hole. Redrilled it to the right size, floxed in new bushings, and bolted the wings to the new spar. After cure and a lot of angst, it seems to have worked out for the best.
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