Part 9: Installing the "Upgrade Package" to our Zodiac CH 601 XL

Picking up where we left off in our last post, here we drill and bolt the cap spacer 6-ZU-1-6 centered between the original spar web 6W3-1 and the new wing root doubler 6-ZU-1-2:

Then we start deburring and riveting some of our Upgrade Package additions permanently into place, starting with the back of the wing, riveting the Top Rear Spar Angles and Doublers... well as the Aileron Bellcrank Support Channel and L-angles:

We lay the top rear skin back into place and Steve measures the location of the Aileron Bellcrank Support Channel's top L-angles...

...and Roger drills through the top rear skin into the L-angles.

Now, we roll the skin back to debur our newly drilled holes.

Here's the video clip of the above activities:

After this first (right) wing, we'll start work on the left wing.

Again, I need to emphasize that we are still working on the Upgrade Package kit right now, and that the three drawings 6-ZU-1, 2, and 3 are still drafts and that Zenair in finalizing 6-ZU-4 referenced in the AMD Safety Alert / Safety Directive dated November 7, 2009.

After we had removed the wings from fuselage, we checked the spar attachment holes using gauge pins:

Despite its age, this demonstrator Zodiac XL is well within tolerance: Using various hole tolerance gauge pins we check the fit of the wing spar attachment holes. We checked all the spar attachment holes and were pleased with the results.

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Comment by Jim Timm on November 17, 2009 at 10:44pm
When inspecting the wing spar attachment holes, what is the acceptable tolerance range for the wing holes and the fuselage holes??

Jim Timm

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