I peeled off the peel ply from the bottom spar cap and sanded it smooth.
The layup schedule was spot on... the cap was perfectly flush and level with the foam surface...
The cap didn't need much sanding..
With the cap all prepped, I focused my attention to the wing attach pocket. A flox fillet is required around the pocket. So I milled out a groove with my dremel...
A good flox corner requires a good flox bond with the existing glass. So I sanded the mating surface clean with a metal file all around...
I then prepped the LWA3 surface, since a 4" overhang from the FC1 leading edge will overlap onto its surface... what you see at the very bottom of LWA3 is a piece of tape that is holding a foam bumper on the underside. I put this foam bumper in place so that if for whatever reason the jigs were to collapse, it would land on the bumper and not pop the LWA3 piece off - just playing it safe.
I also prepped the forward face of the shear web - since it too receives the 4" overlap.
I then cut all UNI plies as indicated on page 19-6 of the plans. I noticed that in the plans, the sketch there shows the left wing, even though its talking about the right wing... but the point on how to cut the uni is clear. Here I am dry fitting the sections on.
I then cut the 45 biased BID piece that reinforces the wing tip.
I then drew the "rabbit ears" to let me know where to apply the peel ply later on next to the wing attach pocket...
With everything prepped, it was time to do the layup. I started out by slurrying the foam, beginning with the first section...
I filled all uneven surfaces with dry micro...
Added flox into the groove for the flox corner pocket...
Added micro to some of the mating edges with the cap to create a nice ramp transition into the cap... even though the surface was pretty much flush with the cap already. I made sure to not get any micro on the cap surface itself.
I then painted plain epoxy onto the cap surface to get a good glass to glass bond with the skin...
Also added some flox to the edges of LWA3 to make a nice transition with the glass that will go over it...
Prepping the surface always seems to take forever! There is a lot going on... slurry, micro, dry micro, flox, wet flox... with all that behind me, it was finally time for the first ply.
IMPORTANT NOTE: I should note that I intentionally skipped over the step to add peel ply along the trailing edge of the wing and along the leading edge of the aileron. This is because I had a really bad experience with this during the canard build back in Chapter 10 - prepping for the top layup.To make the long story short, when embedding peel ply under glass, it becomes extremely difficult to rip the peel ply off later. My plan is to prep any mating surface later by sanding it. Of course, I will have to use extreme caution not to sand too much... but after the experience I had with the canard, I would much rather take this route.
Here we are putting the first ply on.
When dry fitting everything earlier, I noticed that I would have to shift the first ply slightly over so that the root tips would get the proper coverage. The picture below shows how it is about 2" shifted inboard.
With the first section on, it was time to slurry the remainder of the wing... and prep it with dry micro, etc.
Plain epoxy on the cap...
Then added the remaining sections of the first ply.. the sections are butted, not overlapped.
I then measured 4" of overhang on FC1 leading edge... and trimmed the cloth...
With the first ply complete, it was time for the second ply. This ply crosses the first ply as shown in the plans.
Elle helping me wet the cloth out...
Trimmed the 4" overhang...
I let the leading edge just hang...
With the 2nd ply complete... I moved on to laying the 3rd ply - the BID reinforcement on the wing tip...
With all plies wetted out, I trimmed the trailing edge to have less than 1" overhang. I should mention here that I skipped over the step to add micro along the trailing edge groove. At the time, I thought, "I'll just do it post-cure"... but now that I think of it, I should have applied peel ply on the top surface of the trailing edge... now I will have to prep the surface prior to filling it in with micro post-cure.
I then peel plied everything that needed peel ply... the wing attach rabbit ears...
Peel ply on the leading edge...
Peel ply on the butted UNI plies...
The BID section... this one required a large peel ply section... I still had the large roll of peel ply for when I was asked to peel ply the entire surface of the firewall way back in Chapter 4.
The next day after a full cure, it was time to trim all edges flush. And what better way to do this than the router?!
Look at that smooooooth flush trailing edge! Niiiiice....
Of course, I couldn't use the router where the jigs are...
So I drew a continuous line...
And trimmed these parts with the multitool...
Nothing to it. The tape on the jig was a good idea since it protected it from runoff epoxy and from having the overhang stick to the jig...
Perfect!
I now switched focus to the leading edge... I started out by marking the tangent line along the leading edge...
I then used my multitool to trim the leading edge overhang...
This edge gets sanded later to allow a nice transition with the top skin...
Although the plans said to cut the inboard root piece square off section FC4 (at the end of step 4 of this chapter).. I figured it would be easier to cut it after glassing... let me explain...
I started by clamping a straight edge (2x1 strip) to the leading edge of FC1....
I then held a steel square up against the 2x1... aligned the corner up with the root of FC4... and drew the perpendicular line...
Here's the perpendicular line...
I then used my multitool to cut along this line...
Oooooo.... ahhhhhhhh....
I then peeled the fiberglass edge off... the idea will be to do the same thing on the other side (top surface). This will give me a "guide" to run a hacksaw blade along to cut the foam piece off - and guarantee that I do not cut it at an offset angle...
Moving on.. I now switched my attention to the wing attach pocket.
I used my router to remove the "lid" to the pocket...
I then used a file and sandpaper to fine trim around the edge...
Ooooooo.. look at that nice flox corner!
Page 19-12 in the plans shows us how a 3/8" drive ratchet wrench with a 3" extension and a 3/4" socket should fit in the pocket to later bolt the wings onto the center section spar....
I had to test it!! Moment of truth... will it fit? Yuuuuup! Plenty of room!
And there you have it! Right wing bottom skin surface complete!
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