I made 5 1/16" shims and taped them down at designated locations per plan. I did not use any shim at the right rear hinge location since my TB is already resting on top of it (the hinge material is 1/16" thick). The tape was for holding the shims down during the trial fit step. The tapes were removed when I floxed the TB in place later on.
I placed the TB on top of the longerons with its aft end against the firewall. The curvature of the TB fits the firewall very well - its almost flush along the entire seam. However, I noticed the center line of TB-1 was not lined up to the center line of the fuselage. I thought the TB-1 could have been moved when I flox it onto the TB, but I decided to take some measurements to make sure everything is in the right place...
I took the TB off from the top of the fuselage and re-established the center line of the TB - front and back, as well as the TB-1.
I
set up the laser on the center line of the fuselage. Then I place the TB back on
top of the longerons with its new center points (base of TB-1 and mid-point at
the top aft of TB). I was surprised that when everything is line up to center, I
have a gap (~1/4") on one side of the TB and the firewall. The only cause
(I can think of) is the firewall not being perfectly square to the fuselage.
With the TB off again, I took a measurement between the bottom edge of the firewall (left and right) to the centerline on top of F22. Both distances were exactly the same (IIRC it's ~83.5"). The firewall is also vertical per Section 7. I measured and re-measured with no better luck.
I
finally gave up and flox the turtle back in place. Though the plan allows
trimming of the TB by a 1/4", I decided to leave the TB line up to the
center line and use flox to fill in the gap later on. Note the flox fill under
the TB... The 1/16" shim and the sliver of foam are buried inside the flox
fill. My flox fill is more like a sliver because I raised my TB by 1" at
the front.
I
trimmed the TB flanges per plan, then I radius the flange edge to the fuselage
curvature. I further filled the gaps with flox and glassed the permanent part of
the TB in place with 2 layers of BID. I contemplated to use micro instead of
flox but decided not to. I ended up using a lot of flox to fill in the honeycomb
holes - such that there is no bubbles underneath the BID. Should have used
micro???
I filled the gap between the firewall and the aft end of the TB (only the left side had a gap) with flox. Then I smoothed out the seam (as needed) with flox such that the glass will lay down nicely at the transition. Glassed in with 2 plies of BID per Fig. 26 section B-B. I also peel plied the entire BID layer though the plan did not specify.
I have to wait till after Section 11 before I can get inside the TB to finish the glassing of the TB to the fuselage/firewall.