Centre Section Spar

The Cozy MKIV centre section spar joins the wings to the fuselage. The center section spar is the heart of the wing structure.  The top of the spar is flat and the spar sweeps aft and the bottom has positive dihedral so that the fuel runs inboard while in level flight.

We did a trial fit of the spar with the fuselage and need to sand a few rough edges on the fuselage to get a better fit.

After a bit of sanding the spar rough fit into the fuselage.

The spar was moved back to the worktable and all outside surfaces were sanded.

Removed a small amount of foam from the outboard holes on the bottom of the spar. Mixed a small batch of dry micro and applied it to both holes to protect the foam.

Used the dremel tool to make a small flox corner around both outboard bulkheads CS5 & CS8.

Workshop temperature was 24 deg C and humidity 28%.

A batch of epoxy was mixed up and used to make up some micro as well as a small cup of flox.

Epoxy was brushed onto the existing glass edges of the outboard bulkheads then micro was applied to both bulkheads.

Next, the edges were filled with flox to make flox corners.

One layer of BID cloth was placed on each outboard bulkhead at 45 deg orientation and wetted out with epoxy. Lastly, peel ply was added to both layups.

Removed the peel ply from both outboard bulkheads.

Trimmed the glass edges and sanded the edges to be flush with the spar.

Sanded the inside centre section and vacuumed the inside of the spar.