I recently did the upper attach brackets which affix the pitch pushrod
containment bulkhead to the upper fuselage. The manual (original Mk 1 manual
at least) says to glass them in place and then somehow drill neat holes and
install the hardware, all while cocooned back there (in mild pain). The
following method was really easy; it essentially prepares and affixes the
brackets outside of the aircraft:
1) Take a rectangular piece blue foam (2" x 2" x 7"), and grind one face to
match the angle of the upper fuselage where the brackets will be bonded (the
lateral angle, sloping down the sides).
2) Lay up 4 layers of bid on this foam block. After cure, cut out the two
angle brackets (2-1/2" L with 1-1/2" flanges) and sloping rearward like they
would be were they glassed in place. There will be a port and starboard
angle bracket.
3) Take them inside the fuselage, and position them against the
bulkhead sides and the fuselage top. Secure them with two small C-clamps.
4) Remove the bulkhead. Drill the required 3/16" holes, and remove the
clamps. I installed two bolts per bracket, not one per manual -- makes steps
6-7 easier.
5) Attach anchor nuts to the bulkhead with pop rivets. Apply wax to the
vertical bracket faces and the bulkhead, so any Redux seeping there won't do
any harm. Install the brackets with AN-3 bolts and washers, but leave them a
couple turns loose so the brackets flop a bit.
6) Take this assembly, plus some Redux/flox, back into rear fuselage. Check
the fit. Apply the adhesive to the fuselage top and to the top part of the
angle brackets.
7) Slide the assembly rearward in place. Install the lower bracket
bolts. Tightening the upper bolts will squidge the brackets into place.
Wipe away excess Redux, noting especially that you haven't bonded the
bulkhead to the fuselage. Job is done.
Hope this is useful to those facing this task, if someone hasn't found a
better method....
Regards,
Fred Fillinger, A063
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