Strake outside bottom layups


It was now time to flip the bird and get busy on the strake's outside bottom layups! To flip the airplane, I used my engine hoist and a strap to act like a cradle around the front portion of the fuselage...





I then removed the main landing gear, and rotated the fuselage while holding it by the engine mount. I had two other friends help me and make sure everything was coordinated. I have to say, something I thought was going to be a real pain to do ended up taking 2 minutes!





With the bird flipped, it was time to trim the leading edges flush with TLE (fuel tank leading edge) and BLE (baggage leading edge)...


First I used a knife to trim most of the overhang...


Using the dremel, I then removed most of the excess glass/flox (that oozed out when I bonded the bottom skins on)...


Then with a 120 grit palm sander...


And last but not least, fine sanded by hand...


Nice and flush!



I then rounded all leading edges...



Sanded the spar since the fiberglass will overlap onto the spar... also made sure there was no "joggle" per CP#32 under 'builder hints'...





I then focused on prepping the fuel drain (where the fuel will drain into the fuel sump blister)... the plans don't really mention anything about this, simply shows a cross-section on pg 21-6 section H-H... but I wanted a nice glass-to-glass lip around the drain...


So I used a compass to draw a circle with a larger diameter around the drain...


Used a flat-head to remove the foam...


And then used a dremel to help me remove the micro that was under the foam...


Finally, I sanded a bevel all around the drain for a nice transition... and also made sure to sand 0.25" lip to have a nice glass-to-glass bond with the existing glass...


I didn't bother sanding the inner portion of the drain, since I will later use a hole-saw after cure to create the actual drain hole...


Per plans, I also removed the foam around the fuel strain tap... and beveled the foam around it...


Before glassing the bottom surface, I decided to fill the gap between the fuselage and the strake with pour foam... it was about 0.25"-0.5" and thought it was too wide to fill it up with micro!


So I taped a portion off, and poured foam into the void...


I also took this opportunity to patch up the voids that attach the spar to the fuselage...


I gave them one last torque check, and sealed them up!


After the foam cured, I sanded everything nice and flush! Also, I prepped the fuselage sides since the fiberglass will lap onto the fuselage about 1"...


I then focused on trimming the fuel line to final length. The plans say 0.4" max (pg 21-4)...


So I made a mark and trimmed away...


Booom! 0.4" on the money!


Sanded the spar...






I removed the temporary red NPT plugs... I figured it would be easier to glass this without the plug, and use the tap to remove any epoxy later...



With everything prepped, it was time to glass!!! Started out by vacuuming everything, mixed plain epoxy and brushed every surface that was going to have glass overlap onto it..



Slurried the foam surfaces...



Was careful not to get any slurry on the aluminum... or from getting inside...


Put a small micro fillet between the strake and fuselage to help the glass transition the corner...



Made sure to paint plain epoxy on the fuel drain for a nice glass-to-glass bond..


Per plans, first ply of UNI parallel with the leading edge... I then butted up the missing portions and wetted everything out...


I then applied UNI ply #2 (fibers forward and aft)...


Wetted everything out and then applied the 3rd ply (5" on the outboard end).... wetted everything out and peel plied all transitions...














Of course, all this had to be repeated on the other side!


And there you have it! Outside bottom strake layups complete!! (note: I will attach the fuel sump blisters after cure!)


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