Lashing Seat Frame, Lightweight seat cover + More wing work

Craig lacing the new lightweight seat

Over the last week we finished building the first copy of the new lightweight seat, this one lashed with Kevlar (we'll do welded ones as well later this week, and compare to see which works best), and we had a lighter weight seat cover built with medium nylon mesh, which we started installing.

We did some exploration into annealing of the seat frame tubes (for easier bending), and looked into heat treating and the possibility of building our own heat treating oven to bring the seat back from the annealed condition to a stronger T6 temper, after the seat frame has been bent and welded.  (In the end, we'll probably use an existing oven or commercial heat treater -- building an oven will be a lot of work and expense, but is doable in a pinch...)

We made our first cuts on the carbon fiber tubes we received late last year, as we are starting work on the prop shaft for the fuselage.

We also finished up the lashing and epoxying of the main wing, including putting Kevlar patches to join the three parts of the trailing edges, and we marked the ribs in preparation for installing the Kevlar X-bracing.  We'll finish that up later this week, and that will be it for the test section, except for covering with Mylar, which we will do right before covering the first real tail and wing parts, so that we get some recent practice on the test section first.

We've been building things 2 or 3 times a week the last month and a half or so.  Next week, we'll commence continuous building as we push to build the entire airplane over the summer.

Light weight seat cover using medium black nylon mesh

Clips used to hold the Kevlar tow during lashing

Seat frame prepped for lashing, clips in place with hose clamps

Lashing in progress

Video showing lashing of the seat frame

Seat frame fully lashed and epoxied

Excess epoxy, cured

Finished seat frame with cured and trimmed lashing

Closeup of trimmed lashing

Connie trying out the seat frame

Lacing the seat cover

Lacing in place (but not tightened or tied off yet)

Another view with seat cover roughly laced in place

Scribblings on an oven design for heat treating the seat

Trying out outlines for different oven sizes and shapes

Cutting the "fuse tube" part for the prop shaft assembly on the abrasive chop saw

Video of cutting the "Prop Shaft, Rear" part on the abrasive chop saw

Bonding the lashing for the X-bracing loops with epoxy

Bonding the lashing for the X-bracing and rear spar junction of the center support 

Bonding the lashing for the X-bracing and main spar junction of the center support 

Detail of end rib support lashing

Test fitting Mylar peel piece for Kevlar joining piece on trailing edge

Starting the epoxy squeegie-ing of Kevlar joiner on Mylar sheet

Kevlar trailing edge joiner epoxied and clamped in place (one layer each side, plus one extra small strip on front edge)

Cured trailing edge joiner, pre-trimming

Trimmed trailing edge joiner

Marking the location of the X-bracing on a rib