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Gluing on the ribs?

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asport22

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The more I learn, the less I know.

On the Jodel ribs, the verticals at the spar weren't glued on till the ribs were assembled to the spar, so it was simple to put glue on the spar and the verticals, then assemble everything. (Well, there were some alignment challenges, but the glue application was easy.)

Of course, the Acro Sport ribs aren't done that way - they are fully assembled with just enough clearance to slide onto the spar. I am using West Systems epoxy, with the two-step method of first coating the parts with straight epoxy, then adding thickened epoxy on assembly. It's easy enough to paint the epoxy onto the spar, but there is no access to the mating surface of the rib vertical. I just slid the ribs over onto the wet spots on the spar, and hoped for the best, which seems sub-optimal. Then I slid them back over, applied the thickened epoxy, and slid them back into place. Of course, that pretty much scraped all the thickened epoxy off, so I tried with little success to squish it back into the gap with a stick. (The gap ranges from zero to probably 0.020.) Again, sub-optimal.

I did add triangular glue blocks to both sides of the verticals, so I'm pretty confident that the ribs are not coming off. But I still just don't like the idea that there are probably (almost certainly) voids between the spar surfaces and the rib verticals.

So are there any tips on how to do this better? Or should I just accept it and move on?

Thanks!

Warren
 

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