Sunday, August 21, 2011

Vans Aircraft RV-12 Build, Section 18: Flaperon (part 4)

Today will finish the flaperon for the RV-12 aircraft. It interesting because to date I have a total of 238 hours into the project. The wings have taken 136.5 hours. By comparison at this point on the RV-10 I had 822 hours into the build. True it is an apples to oranges comparison but it still illustrative how fast the RV-12 goes together.

Reference: page 18-06; 6.5 hours

Step 2: When satisfied with the fit of the Outbrd Flaperonskin and Inbd flaperon Skin, rivet the outbd flaperon skin and inbd flaperon skin to the A-1205Main Ribs and to each other.

Builders note: On the opposing trailing edge rivets I ran in to the situation where they bottom out on the rivet from the other side (see picture below.) To deal with this problem I used a hand rivet puller and gently pushed the rivet into place as it was slowly squeezed (see second picture below.).

Step 3: Cleco the Outbd Nose Skin to the under structure as shown in figure 1 on page 18-06 on Van's Aircraft plans. Rivet the outbd nose skin to the under structure EXCEPT along its inboard edge where the Mid Nose Skin overlaps as shown in Figure 1 of the RV-12 plans.

Step 4: Cleco the INbd Nose Skin to the under structure as shown. Match-Drill #30 the holes common between the inbd nose skin and the InbdNose Ribs. Insert a cleco after each hole is drilled. Remove the #40 clecos from each inbd nose rib and final drill #40.

Step 5: Remove the A-1201A-L Inbd Nose Skin and deburr all match-drilled holes.

Cleco the Inbd Nose Skin and the Mid Nose Skin to the under structure. Rivet the inbd and mid nose skins to the under structure using the rivets called-out.

Step 6: The mid and outboard flaperon hinge points use rod-end bearings threaded into the A-1206 Pivot Brackets as shown in Figure 2 on page 18-06 of the RV-12 plans. Apply a thin film of Loctite 243 to the first third of the threads of each rod-end bearing before installation into the pivot bracket. Wipe-off any Loctite that is visable after the installing the rod-end bearing.

Place the flaperon on a horizontal surface with rod-end bearings pointing up and allow the Loctite to cure for 24 hours.

Builders note: To measure the height of the rod end bearings I temporarily installed a long AN3 bolt leveled with respect to the skin and measure from the bottom of the bolt on both sides of the rod bearing. Instead of using 11/32" from the center of the hole, I measure 8/32" from the bottom of the bolt to the skin. (11/32" - 3/32" [half the diameter of the bolt] = 8/32".) Then I ensured the rod ends were perpendicular to the edge of the nose skin.

That completes page 18-06 and the flaperons of the RV-12. Next to come is the construction of the fuselage. For anyone who is interested I have gone through ~24 spray cans of zinc chromate primer to this point.