Right wing - shear web

This was a pretty straight forward, 'problem free' layup... although it did take about 6 hours to complete - one hour for prep, 4 hours for the layup, and one hour to add the LWA2 and LWA3 pads and pucks.

The day prior, I cut the 12 pieces of UNI required for the shear web layup. The plans say to cut twelve 13" wide UNI sections at 45; however, before I started cutting, I looked at the shear web and noticed that it is much thicker at the root of the wing than it is at the outboard tip. So I measured a rough distance around the root and at the tip.

Instead of cutting all 12 pieces the same width, I decided to add more skirt overhang.. so I ended up cutting six of the twelve pieces 16" wide... and six 14" wide. I like to have a bit more playing room with the overhang skirts, as I noticed from past experience that the plans typically don't allow for much wiggle room.


I micro'd the LWA4 and LWA6 pucks in place...


Here is the inboard LWA6 puck...





Here are the outboard LWA4 pucks...





I then cleaned up the excess micro and moved on to micro the WI8 plates...


Nice fit!!


I then repeated it for the other side...


I waited for these to cure overnight and then proceeded with the shear web layup the following day.

I started out by sanding all cured micro runoff from bonding the FC sections and LWA pucks. Actually, I didn't sand them - I used my dremel at really slow speed to remove runoff micro. I found this method to be quicker and much cleaner since sanding removes a lot of the foam.

After all surfaces were smooth, I slurried the shear web...


Made sure to cover every square inch of the shear web... the heavy stuff with a squeegee and then the brush to spread it all out...



I added dry micro to any voids.. especially on the seams where the FC sections met...


I made sure to NOT cover any of the aluminum surfaces with micro. I mixed up some wet flox and covered the pucks with it...


The WI8 plates also get a small amount of wet flox...


The surface was now ready for the first ply.


I made sure to use the 16" wide pieces for the inboard most sections... and the 14" wide pieces for the middle and outboard most sections.


I had previously marked where the sections should go. This was very helpful in making sure the pieces were not being stretched or deformed.


The first ply is always the hardest, as I had to make sure all surfaces were properly transitioning between the foam and aluminum pucks...


Here is a good shot showing the sections are butted.. not overlapped...


It takes 3 pieces to cover the full span. The second ply is at the opposing 45 degree bias.


The third and fourth ply only get an inboard and middle section. Notice the skirt overhang.. this gets trimmed later...


Elle helping me wet out the cloth...


The last two plies go on the inboard section only.


Now time to trim that overhang...


I put a new blade on and gently cut the skirt using a plastic card to hold everything in place right on the shelf line...


I then peel plied the spar cap sides...



It was now time to bond LWA2 and LWA3 pucks...



The plans say to add a 3-ply BID pad at 45. Although I was aware of CP 26 (LPC #31) that states it should be a 2-ply pad, I went with 3 plies instead.

Although the surface of the shear web was still wet, I painted on a thin layer of newly mixed plain epoxy to freshen up the bonding area...


And applied the 4"x4" 3-ply pad...


Added wet flox to LWA2...


And bonded it in place.


Section view B-B and C-C in the plans (on page 19-12 and 19-13) show how they cantilever out a bit. The spar caps later go under this cantilevered lip.


Same for LWA3... first I painted plain epoxy onto the surface...


3-ply 4" x 6" pad...


Wet flox onto LWA3...


Bonded it in place..



I then peel plied the pad edges...





Added cling wrap to allow me to place weights on the pucks...



Used full epoxy cans to weigh the pucks in place.



Right wing shear web complete!




The next day, I had to trim the ends.


Multitool in action...


Snip snip...


Other end...


Snip snip...


I then used my router to trim the ends perfectly flush with the foam surface...


Next up... bonding the leading edge and bottom spar cap!

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