Flaps

This blog cover the assembly of the flaps

Overview
Both flaps were supplied assembled with the necessary twist at the factory only requiring triming of the skins and final assembly.

Assembly.
The nose skin is held with a few temporary rivets that were removed allowing trimming of the nose skins to size. Both skins were trimmed using a Ofla knife giving 10 mm from the rivet line as per the factory standard, then all edges were then filed and polished using wet / dry paper before installation.

Note: The factory uses a series of 5/32 dome head rivets to hold the assembly in alignment  these were removed to ensure the nose skin would be flat. This removal makes the initial reassembly difficult so under no circumstance chase drill any holes they will slot.

The nose was then reinstalled using clecos with the first few being difficult due to the twist required in the flap but once the basic alignment was re-established all the others were installed relatively easily.

All work assembly was done on the aircraft using the flap hinges to ensure alignment and just because is was convenient. All rivets used were domes but countersunk rivets were used on the top side of the nose to ensure no possibility of a foul with the shroud.

In the blog on the shroud it was mentioned that attention should be paid to the alignment of the shroud lower edge, well this was because this builder failed, though not all that bad it could not be left as it was.

Shroud with new lower edge

To fix the problem a new lower edge was fabricated from 0.5 mm aluminium sheet, match drilled to the rear spar. The aluminium shroud was then trimmed to the back edge of the skin and then match drilled through the new edge and then dimpled for assembly.

Cover Strips

The shroud has to be drilled to pick up tabs on the brackets  that support the top skin that covers the flap. They have a habit of bending and the aluminium on the shroud is very soft and will tear easily. To make the forming easier it was decided to add a curved strip to align the skin of the shroud. 

A strip 25 mm wide was formed from 1.0 mm aluminium and fixed to the tabs with structural double sided tape.

The next problem was drilling the holes, these will tear due to the softness of the aluminium used, so it was decided to use a series of small jigs to drill the holes and were fabricated from scrap 2024-T3.

With the location of the tabs marked the jigs were held in position and the holes drilled, once done a cleco was added. The addition of the curved strips assisted maintaining/creating a smooth profile.

The shroud was reinstalled under the folded edge as described earlier but it was noted that the starboard side had small but distinct inflection. It was concluded that this was a result of all the fitting and refitting so the first two rivets holding the cover were removed and to hold the cover straight / flat then two beads of polyurethane adhesive were applied onto the underside of the shroud and reinserted. Finally a length of angle and clamps were fitted to hold the assembly flat / straight while the adhesive dried, it has a long working time and will drie flexible but slowly - like 48 hours.

Note: Doing it again these rivets on the brackets would be removed and replaced by clecos to avoid forcing up the edge.

That's about the lot

Comment
Was the extra work required - not really but at least the builder is happy with the final result.

I left in hope a that all is OK when the clamps are removed, reminds you of that line "Life is like a box of chocolates" - we shall see as there is nowhere to hide.

Wings Assembly

This blog covers final assembly and associated details for the wings - both wings share common details but the photos are a mix from both.

Overview
Task to assemble all the hardware into the wings for skinning.

Installation
The first task was to install all the piping for the return lines and for the pickups for the external [future] tanks. A trail fit of a tank previously showed a clash with the fuel sender required a U to route around it plus a few Aeroflow fittings. At this time the pitot tube and wiring were loomed and installed on the underside of the ribs. The wires cover strobes and power /signal for the under wings tanks on both sides.

Note: All fittings are all full flow not 90 degree as per aircraft AN fittings

With the pipes installed the tank was fitted to allow connection and fitting of  the components onto the tank.

Note: Last rib is only clecoed allowing all the tank fittings to be installed except the fuel cap which is last.

External tank fuel and electrical connections
Access hatch is for service and connection when commissioned 

Fuel return and delivery lines from external tanks port side

Fuel delivery line from external tanks. Loom is for strobes and external tanks pump / low fuel indicator

These photos are from the starboard side and are a duplicate of the arrangement on the port side.

The skins were installed and clecoed from the underside to provide access and to locate the ribs allowing the tubes and electrical to be cut and installed.

The leading edges of these wings are dimpled and without doubt this has quadrupled the work to install the skins. 

In particular when installing the stringers the skins were removed and reinstalled to many times to count providing access or alignment for the top or bottom stringer and then at either end to install the T clips shown below.

The connection to the check valves at the end of the tank have been changed from rubber to aluminium as I had to purchase a new roll of aluminium and it was there and lighter.

Work on the piping was much easier as it was really a copy of the port side and visa versa for the working and associated clips.

It was decided to fix the stringers to the ribs using a T clip made from 2024-T3 aluminium to place the stringer flush with the skin from rib 7 to 4 and then fit a 0.025'' packer from rib 4 to 1 

In the photograph below there there is 0.05'' of metal [rib and skin] and the Tee will place the face of the stringer flush with the top side of the outer skin when the next skin is placed on the wing.

The Tee is at odd angles because the stringer runs at an angle to the spar because of the wings taper with 0.040'' chosen for stiffness and ability to be countersunk 
All holes are 120 degrees to suit pop rivets

Comment

The tanks will be covered in a separate blog to keep it tidy but they are integral to this process and they were removed and reinstalled too many times for fitting.

There are a number of small items to add and these will all be covered in a final wrap up blog on the wings. 

The final word is below - port next but running out of clecos

More on the underside