Overview
With the painting next the rear fiberglass was finally dressed up and installed with the correct screws along with all those final adjustments.
Installation
The lower rudder fairing lights were connected via a four [4] pin plug mounted onto the first bulkhead after the fin attachment. To do this the cable in the fairing was drawn out and connected to the plug and then feed back in into faring then the faring was secured with a flat head M3 screws.
The elevator faring were next and again secured with the M3 pan head socket head screws with the rudder stab fairings fixed with flat head phillips M3 screws.
Next was the dorsal fin here a couple of holes were re-established using a hole finder and after a series of adjustments it was screwed to the back of the fuselage using M3 flat head screws. The connecting cables from the the stab and trim tab had previously been connected and it was a matter of checking and fixing the dorsal fin.
Finally the rudder stab fairings were installed. As these have to be removed at the 100 hourly to inspect my nick in the spar they were fixed using M3 pan head screws with an incorporated washer. The starboard faring required some more modifications at this time as it did not fit a cleanly.
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Note: All Rivet Nuts were re-tapped with a M3 tap to improve screw installation and avoid cross threading
Fixing holes
Some of the holes had to be relocated, tuned pick a word this is one reason floating nuts exist. When required the correct center was marked onto the surface with a biro in the form of a cross. Next a small amount of Plasti-Bond was mixed and the hole filled then a strip of peel applied across both sides and the mixture squeezed between the fingers and set aside to cute.
When cured the new hole center was re-established and drilled with a 2.5 mm drill before sanding. Once shaped the hole was enlarged with the Dremel motor tool as described previously.
Priming
With this done they were removed and all holes in the fiberglass enlarged to about 3/16'' using a conical grinding stone found in the Dremel kit, this gave a clean hole that could not be achieved with drills.
All fairings were primed using rattle pack bumper bar primer and left to be sanded just before painting
Comments
With the rudder and elevator stab fairings I would not remove the waste to the factory line just straighten both edges equally on both sides as the extra material would allow the fixings to be installed in a flat area the faring. Allow the faring to lie naturally as mine needs a push and shove to line up as pressure was applied before drilling mounting holes.
Note: Pressure was applied when drilling the hole to flatten out the curve and the movement when tightening up the screws created variability creating hole movement, in fact they fit differently every time if only a little. If riveting consider fixing the lower flange and then drill and fix the upper the upper.
The rivet nuts are a mixed blessing as without them the M3 large head screws could not have been used but they make the installation the holes more difficult. There biggest downside is the hole locations are more critical even with 5 mm hole but I was thinking floating nuts when doing the hole filling.
Pop rivets would be the quickest but there are reasons on this project and screws do allow you to adjust pressure obtaining a neater fit.
Above all make sure you mark out the ribs and spar before drilling.
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