Page 14-7 gives us the exact dimensions these panels need to be - all cut from H100 divinycell.
Before bonding the panels to the box, they receive 1-ply BID at 45 degree bias on what will be the interior face. Here I am cutting out BID. Since my workbench is used up by the jig and spar assembly, I placed protective paper on my shop floor and cut the BID there. I took proper precaution by sweeping and vacuuming before placing the protective paper on the ground - then placed the BID over the paper.
Once I had all my BID cut to size, it was time to glass! I can't remember the last time I had a simple, flat-plane layup! Brings back good ol' Chapter 4 memories!
Nothing new here... slurry on foam...
1-ply BID wetted out..
And peel ply around all edges. My temporary workbench is a foldable table I bought from Home Depot - and it's not very level (it has an uneven step down the middle). Since I want the panel to cure flat and level, I moved it to another workstation I set up that is flat and level.
CS4 panels cured...
It was now time to trim all the edges. I started out by trimming all around using the bandsaw...
I then trimmed all the edges flush using my router table... this thing is wonderful! Best $60 I've ever spent!
Close up of the router bit trimming the fiberglass flush with the foam edge...
All CS4 panels... ready to go!!
Before bonding them to the spar box, I wanted to verify all panels matched the dimensions shown on page 14-7...
All was good except for a small kink on the forward lip of the center CS4 middle panel. I simply marked up where it needed a bit of trimming...
And trimmed away to have a perfectly straight forward lip. Here I am verifying its straightness by propping it up and looking for any light shinning through. I also made sure the right side sweep matched the left side weep...
Here is the right side weep...
Here is the left side weep... all looking great!
When I placed the middle panel into position, I noticed that CS3 needed minor adjusting to match the edge of the panel.
So I lined up the panel with CS2 (along the jig's backboard) and placed six 2" nails along that line. I then stuck my hand inside of the box and pushed CS3 out a bit until it aligned with the forward edge of CS4. With my other hand, I inserted the forward row of nails in order to hold CS3 in place. CS3 and CS4 edges are now perfectly flush.
Before I could test fit the side CS4 panels, I had to trim the fiberglass corners a bit. Here I am using a metal file to get a nice clean corner.
Oooooo.. looking goooood!
Yup, perfectly flush!
I should note that I beveled the edge that mates with the center panel...
I then sanded all the jagged edges of the reinforcement layups smooth. I will later be sticking my hands inside this box to install the wing's nuts/bolts.. don't want to end up with any cuts when I do!
Also sanded the interior bulkheads flush with CS2 and CS3...
And of course, all fiberglass mating edges flush...
I then vacuumed the interior and had one final test fit before bonding time! I should note here that I skipped over the recommendation of fellow builders to install a conduit inside the spar box. The idea is to be able to run cables from the wing tips through the wing, through the spar box and into the aft end of the fuselage. Since I am planning on running my cables through the leading edge of the wing (and through conduits I installed inside the fuselage wall panels), I decided to omit this mod. Worst case scenario, I will just have to fish the cables through the hard way.
With all pieces properly trimmed and sanded, it was time to bond the panels on! I started out by applying wet micro to the top faces of the middle section..
I installed the middle CS4 panel by first inserting the CS2 nails. Again, sticking my hand inside the box and pushing CS3 out until the forward nails found their happy spot. I then placed 2x4 pucks and weights on top. You can see the access micro spilling out...
I then repeated the process for the side panels. Notice how I also applied micro on the top edge of the interior bulkhead. I cleaned up the excess before installing the panel.
Here's a better view of the interior bulkhead top edge with micro...
I then applied 2x1 pucks and placed a few 2x4's on top for weight...
I added weight to the center section by filling up 3 gallon trash buckets up with water. I then removed all excess micro and let cure.
Next up will be removing the box from the jig and prepping it to receive the top and bottom spar cap layups! I have to wait 3 days for a full cure (per plans) before touching it.
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