Wing J-Stringers centerline

Got just up to installing the W-926A/B j stringers in my wing today. I drew the center line as per the plans (3/8" from unbent end). When I install it in the wing the line is too high and I cannot lower it any more since it is hitting the ribs. Seems like I could just install the j-stringers touching the ribs and not need the line. What have other people done?

thanks

I adjusted the distance slightly (5/16" instead of 3/8") to keep the stringers from hitting the ribs. I'm pretty sure I've seen other builder web logs that mention this issue.



The plans also wrongly call out for the end of the stringer to go to the end of the skin. It just needs to go flush with the rib. Otherwise it will interfere with the fiberglass tips.

that is exactly what we did as well... just changed where the line is so it is centred in the cut-out in the rib.
when you install them, put both a and b in so the overlap(about 3 rivet holes worth) can be slightly adjusted to keep it centred.

Yup - what they said.

Here's another tip for you - cut the J-stringer flush with the end of the rib on the wingtip end (like Bruce's picture) instead of letting them run long to the edge of the skin. When it's time to put the fiberglass wingtips on you'll end up taking a dremel tool to that J-stringer otherwise.

Ask me how I know...

Thanks!

Thanks for the advice. That measurement work out perfect. I caught the extra length on the wingtip side and made the executive decision to make it flush with the rib the first time I slid it in. Figured since there was no rivet hole past the rib it wasn't necessary.

It depends on the side. This one I cut short and the next one was installed correct.

pilot2512 said:

Thanks for the advice. That measurement work out perfect. I caught the extra length on the wingtip side and made the executive decision to make it flush with the rib the first time I slid it in. Figured since there was no rivet hole past the rib it wasn't necessary.

Click to expand...

Good work...

Still a gotcha.

I bought my wing kit in the spring of 2018 and the assembly instructions still have the same issues: 1) calls for 3/8" but should be more like 5/16", and 2) calls for aligning with edge of W-903 but should be W-902.

For the record, I'll be taking a dremel (as stated in a prior post) to the first wing I built. I finally realized the problem AFTER match drilling the j stringer on the second wing. At least I can trim that one before final assembly.

I glad to hear that planes are not falling out of the sky having that extra half inch gap between the outer stringer and the inboard skin.