Strake outside top layups


With the bottom strakes' outside layups and fuel blisters complete, it was now time to flip the bird right-side-up and glass the strakes' top outside layups.

To flip the bird, I tied a strap around the front portion of the fuselage and lifted it slightly with an engine hoist...





I placed the strap between the leading edge of the strake and the instrument panel so that if it were to slip off, it would be "locked" in place...


With the help of two friends, I lifted the fuselage from the engine mount (by hand standing on a step ladder to give me more height)... they removed the stands from underneath and rotated the fuselage up-right like a rotisserie... then slid the stands back in place. The whole process took less than 5-minutes!


Taaaa-daaaaa!!! Airplane is right-side up again!


Now to get busy cleaning up the leading edges...





And the blobs of Liquid Nails left behind from the 2x1's...


And the OD outboard diagonal rib edges...


All this overhang had to be sanded down flush...


With all that work out of the way, I noticed something that was bugging me...


When I placed a straight edge along the leading edge...


I noticed there was a half inch gap. CP#30 under "Builder hints" warns us about this. When I installed the top skin, I remember thinking that the OD can be shaped later and will fix itself. What ended up happening was that the top strake skin was too stiff and once bonded to R45, it will not want to spline with the OD. In other words, the OD rib's shape is based on the top and bottom strake skins (rather than making the OD the shape you want and having the top skin conform to it as said in the CP).


So there I was... contemplating what to do.. leave the divot and fill it later? Or slap some liquid foam over low area and sand it flush? I went with the latter... here I am attaching a piece of cardboard to the leading edge to act like a dam and keep the liquid foam from spilling over...


Nothing fancy.. just taped cardboard to the leading edge...


This should hold the liquid foam...


So I mixed up some liquid foam and poured it over the front portions of the strakes..


Waited 30 minutes for it to expand and cure..


I then started carving, shaping and sanding...


Other side had the same issue.. so I repeated the process there as well...



After a few hours... I had both sides leveled and flush! I should note that the strake's leading edges (per plans) do not connect with the wings in a "straight line". For more information on this, be sure to read this post: strake fairing kink.


Super happy with the shape of the strake's leading edge now! It blends with the OD rib in a perfect line!






I made sure to prep all leading edge surfaces for a good glass-to-glass bond...



Also prepped all surfaces that were going to get glass overlap...


Also sanded and prepped the top surface of the spar. CP#32 warns us to not have a joggle between the top strake foam and the spar. With everything prepped, I wetted all surfaces that were going to be overlapped with plain epoxy, dry micro on large voids, slurried all foam surfaces..


Also put micro to fill the small void between the fuselage and top strake foam...


All voids filled with dry micro and slurried the foam...


Plain epoxy on the side of the fuselage.. since that will be overlapped...



Plain epoxy on the leading edges...



Made sure to put epoxy along the seam where the foam skin comes in contact with the spar.. just to guarantee no leaks... also painted plain epoxy on the top surface of the spar..


With everything prepped, it was time for the first ply!


UNI parallel with the strake's leading edge... the back corner also got UNI (butted, no overlap)...


Then the 2nd UNI ply... this time fwd-aft orientation...





The 3rd ply is a 5" strip of UNI parallel with the OD rib...


I left the layup long and trimmed it post-cure...


I thought I could do both layups in one day, but actually decided to hold off! And glad I did because these layups are exhausting! Sure it's only 2 plies (plus the 5" OD ply), but there is SOOOO much surface area that my hand hurt just from mixing so much epoxy!

The next day, I repeated everything for the left strake...













The plans say to add a 4th ply on the left top strake only to handle any foot traffic that the passenger might produce over the years of getting in and out....


As some builders in the past have done, I added a strip of carbon fiber just to reinforce this foot traffic.


I then peel plied everything and let cure...


Close up of the carbon fiber! Man, I love this stuff! Looks so cool!











A few days later, I  cleaned everything up and put the wings, canard and canopy back on to see how it looked fully assemble... sometimes you have to do things for a motivational boost! WOW!!! I'm sure glad I did because I can't express what I felt when I saw everything come together!


I still have to complete the strake's leading edges, leak test the tanks, add fuel caps, etc... but looking at the airplane like this sure gives me a great sense of accomplishment... and finally starting to see a glimmer of the light at the end of the tunnel!


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