Originally Posted by Maxrate
How far down does the aft flange spacer go? Does it go as far down as the keeper rivets? Also, does it taper in thickness? Thick at the top, thinner at the bottom? Thanks for the details. I’m going to have to do something similar.
The shim is .025" (not tapered) and is 1⅜" deep and not quite as wide as the rear flange.
The shim does not make it to the keeper rivets. (From just above the keeper rivets to the bottom of the aft flange, the flange fits tight up against the F-712 bulkhead)
The plan is the shim will be captured when the vertical stabilizer bolt holes are drilled.
When sizing the shim I pushed some .025 stock into the gap until it would not go any further...marked it and fashioned a shim of that depth. Then I inserted the shim into the gap and drove it down until it was flush with the top of the WD-409 rear flange.
The problem with my installation was the Quick Build fuselage F-712 aft bulkhead would turn concave when installed...removed, it was flat.
I had already installed a .064" shim between the forward WD-409 flange and F-711 bulkhead.
The F-712 aft bulkhead was so difficult to install after adding the forward shims I really did not want to take everything apart. Ergo - the aft shim being driven in without disassembly.
You can see the concave F-712 aft bulkhead in the photo below (this was taken before adding any shims). After adding the forward shim the aft flange still looked like this photo but not as severe.