A few minutes later, I had two foam tabs.
But before I could bond them onto the canard, I had to shim the canard square and level.
I used squeegee cards between the F22 bulkhead and bottom lift tabs...
I also shimmed under the canard to get proper level...
Making sure the canard incidence was perfect. Of course, I made sure the fuselage longerons were also level.
I used a shim between the alignment pin and the canard to press the canard down a bit to get the incidence exactly where it needed to be.
Looks good to me!
I had two levels.. one on the left outboard end and one on the right outboard end. I also measure the distance from the canard outboard ends to the spar's outboard ends.. I was surprised that they were within 1/16"!
Happy with the canard's placement, I was ready to bond the foam tabs in. I used my caliper's depth gauge to measure how tall the tabs had to be...
I then brought it over to the foam tabs and trimmed them to size...
Before using 5-min to bond them in, I placed plastic wrap onto the F28 bulkhead so they wouldn't bond to it..
Cleaned up all the surfaces and performed a dry test fit... I will mention that I failed to shim the back side of the tab by 1/16" as the plans state - this is to make up for the CN2 bushing heads later on. Since I missed this step, I later had to add more padding to the F22 bulkheads by 1/16".
I had to trim the outboard edge of the tab a bit to match my fuselage contour for both tabs...
I then used 5-min to bond the tabs in place.
Notice how I had to remove my shims under the alignment pin.. so I took some 2x1 shims and placed them between the F28's center and the canard... of course, I rechecked canard incidence and all alignments.
Even though I used 5-min, I let them cure overnight. The next day, I prepped the fwd face of the F22 for the shim layups (the layups that pad the F22 to get the canard where it needs to be).
I used my calipers to measure how much padding I needed from the shims and cut BID pads at 45. I also went ahead a cut the glass needed for the top tab layups.
I started out by focusing on the top tab fwd layups. I prepped the canard top by sanding the mating surfaces. I then painted plain epoxy and applied a flox fillet..
I prepregged the 5-plies of BID and installed them in place... peel plied the edges for a smooth transition.
I then painted plain epoxy onto the fwd faces of the F22 bulkhead mating surfaces, prepregged the pads and installed them in place.
After cure, I trimmed everything up..
I rough trimmed the edges...
And then sanded everything clean...
I then reopened the tab holes..
With the fwd face of the tabs complete, it was now time for the aft faces...
First step was to clean up the 5-min epoxy and round the corners smooth...
Looking gooooood!
I painted plain epoxy onto the mating surfaces...
Prepregged the 4-plies...
And installled them in place...
Next day, I trimmed and cleaned everything up...
In order to reopen the tab holes, I had to drill from the fwd face... which meant the canard was going to get in the way of the drill... so I used the flex extension bit...
Perfect clearance...
And the tab holes were reopened...
Top tabs complete!!
I then opened the holes up to fit the CN2 bushings...
I then reinstalled the canard and remeasured the incidence and alignment. That's when I noticed something was off! The CN2 bushing head was pushing the canard top tabs forward, causing a canard to pitch nose down. That's when I realized I failed to shim the tabs forward by 1/16" as the plans stated!
The solution was pretty simple - add 1/16" of padding to the F22 bulkhead. This moved the canard forward by 1/16", allowing proper clearance for the CN2 bushing heads on the top tabs.
I then cleaned everything up and got ready to drill through the F22 bulkhead! Stay tuned!
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