So I was reading some posts on Van Air Force about shims and using a flexible epoxy called Hysol as a “liquid shim” in areas where the skin-to-structure fit isn’t so good.  So as an experiment I bought some Hysol EA9394 from SkyGeek and tried it out, first on the conical bends at the rear baggage compartment floor.

The stuff comes in a two-part pack.  After I mixed it up, I troweled it into a syringe…

…and injected it into the areas around the conical bend where the aft skin tabs don’t nest so well into the center skins.  The Hysol should fill any gap between the tab and skin, hopefully preventing big dimples when the rivets are set.

I had a little Hysol left over, so I shot some into the gaps left by poorly-fitting aux longerons in the forward fuse.  Vans makes these parts by joggling the ends, which means that some areas don’t fit so well.

The proof will be in how the skins look when we rivet them…I hope this wasn’t a waste of a day.