Twisted: Flaps, elevators and first boo-boo

Last week I made further progress with the flaps and elevators.

With the flaps I have begun installing the outer hinge pin - which is going to support not only the flap but also go through the bearing in the rib already part of the wing and into the Aileron. One hinge pin shared by both control surfaces. The pin is flocked in place on the inner rib then a further outer rib is superglued to hold it in position while the flock dries. This job is like most and has to be millimetre perfect. So many hours were spent filing and checking to make sure the pin ends up in just the right place.

This week I will radius the outer rib and reinforce with glass tape.

Other work done was to the ribs on the tailplane (which support the elevators when not connected to the fuselage). After making threads in these ribs and washers a bore hole is made in the rib inside the elevator itself. Again this has to be millimetre perfect so I really went very slow and careful on this job. Lots of checking and remeasuring all the time. I will also reinforce these ribs this week the same as the flaps.

The aileron outboard hinge pin bearings are also halfway through being reinforced - I decided to do one side at a time - too messy and fiddly to try to do both sides at once. The bearing will have to be freed up after the glassing - I've already done this once after the flocking (I also had to do this to the bearings in the aileron horns).

Also a bit upset with myself as I discovered I had made a mistake with the supporting ribs on the wings for the flaps. The diagram in the instructions showed them being parallel to the flap and wing edge (same as the ribs that will go in the flap - which seemed to make sense). Then re-reading the instructions afterwards I saw that they must be 90 degrees to the wing trailing edge rib. Bugger...

This wouldn't have been a problem had I discovered my mistake at the superglue stage - before using flock to radius the edges. 2 hours of careful grinding with the Dremel later and I was able to remove the ribs and re-set them at 90 degrees.

Lesson learnt x3. 1. Read all the instructions - not just looking at diagrams. 2. Not only that but understand what you are doing and why. In other words if I had thought about the function of the flap when completed then the 90 degrees would have been the logical angle as this is the plane of operation for the flap when installed. 3. Re-check the work that has been done at a stage when it is still easy to change it.

It's not such a big deal as it is fixed now but it has added about 3 hours of extra work, however I'm glad to have learned this lesson at an early stage and when I can still fix it.