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.

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

Reference: page 18-05, page 18-06; 5.5 hours

The cool things about flaperons on the RV-12 are, few production planes have them and it sure saves build time and weigh compared to building four separate wing control surfaces.

Step 1: Rivet the A-1207-L Actuation Bracket (outboard row of rivets only), A-1206 Pivot Brackets and A-1203 Spar together per the callouts in the RV-12 plans on page 18-05 figure 1.



Step 2: Cleco ten of 12 A-1205 Main Ribs to the A-1203 Spar. Leave the 5th rib from the inboard end and the most outboard main rib un-clecoed. Rivet the main ribs to the spar using the rivets called-out in Van's Aircraft plans.



Builders note: I found by squeezing the ribs as shown above they were easier to insert into the spar.





Step 3: Cleco the inbd Nose Rib & Bracket Assembly, A-1203-R Inbd Nose Rib, the remaining two A-1205 Main Ribs, and the A-909/A-1204-L & -R Outbd Nose Rib/Counterbalance Assembly to the A-1203 Spar.





Step 4: Rivet all the parts assembled in Step 2 together per the callouts in figure 1 of the plans.







Reference: page 18-06

Step 1: Cleco the A-1202B Outbd Flaperon Skin and A-1202A-L Inbd Flaperon Skin to the A-1205 Main Ribs and A-1203 Spar. Checl that the inbd flaperon skins are bent properly as shown on page 18-06 figure 2 of the RV-12 plans. If not, work the inbd and out bd flaperson skins by hand until they lie flat against the main ribs.



Builders note: My RV-12 flaperon skins needed a little extra bent to lay flat. So I placed them on a solid surface and carefully creased them by hand much the same as you would crease a paper fold for a paper airplane.



Next time I will finish the flaprons off. Until then, take care!

Vans Aircraft RV-12 Build, Section 18: Flaperon (part 3)

Reference: page 18-03, page 180-04; 3 hours

Well, the flaperons for the RV-12 are going smoothly. As soon as I finish this section I will do a time comparison between the RV-12 and the RV10. But I can tell you right now the RV-12 is hands down much fast to build.

Step 3: Un-cleco all the parts. Deburr the two holes just drilled into the A-909 Aileron Counterbalance. Rivet the A-1204-L & -R Outbd Nose Ribs to the aileron counterbalance.





Step 4: Cleco the A-1204-L & R Outbd Nose Ribs/A909 Aileron Counterbalance sub assembly to the A-1203 Spar. Cleco the A-1201C-L Outbd Nose Skin to the spar and outbd nose ribs.



Step 5: Match-Drill #30 the holes of the A-1201C-L Outbd Nose Skin into the A-909 Ailron Counterbalance. See "match-drill" call-outs in Figure 3 of Van's Aircraft plans for the RV-12.

Because of the hardness of the stainless steel I prefer to match drill with a #40 drill bit first and then final drill with the #30. In the pictures below you can see why. The First picture is a #40 hole. Note the drill bit "walked" while drilling making for a ugly pilot hole. However, when it was final drilled #30 it completely cleaned the hole up. The slight unevenness of the hole in the bottom picture is due the the camera angle to the piece.





Match-drill 330 the holes of the outbd nose skin into the upper flanges of the A-1204-L & -R Outbd Noe Ribs.

Remove the #40 cleco holding the out bodnose skin to the upper flange of each outbd nose rib and final drill #30.




Step 6: Un-cleco all parts. Deburr all holes in the A-909 Aileron Counterbalance and all holes in the A-1204-L & _r Outbd Nose Ribs and A-1201C-L Outbd Nose Skin that were either matchdrilled or final drilled.

This completes all steps on page 18-03.

Reference: page18-04

Step 3: Rivet the A-1208 Bracket to the A-1210-L Inbd Nose Rib per the callout in Figure 2.



Step 4: Cleco two A-1206 Pivot Brackets and the Inbd Nose Rib & Brakcet Assembly to the A-1203 Spar.





Step 5: Insert an AN3 Bolt thourgh the hole in the A-1208 Bracket and A-1207-L Actuation Bracket. use washers to space the parts as shown in Fidure 3 on page 18-04 of the RV-12 plans.



Step 6: Align the sides of the A-1207-l Actuation Bracket and A-1206 Pivot Brackets perpendicular with the upper edge of the A-1203 Spar. Match-drill #30 the holes in the spar into the actuation bracket and pivot bracket. Cleco as you drill.







Step 7: Remove the A-1206 Pivot Brackets, A-1207-L Actuation Brackets, and Inbd Nose Rib & Brackets Assembly from the A-1203 Spar and deburr all holes in all parts that were match-drilled.

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

Reference: page 180-04; 3.5 hours

Today's entry covers the deburring of all the remaining RV-12 flaperon parts, prepping and then priming them. This is not a hard task it just takes time.

Step 8: Inspect the outside edges of all A-1204 Outbd Nose Ribs, and A-1205 Main Ribs, and deburr any edges that are left sharp from the manufacturing process and may scratch the mating skins or spar. during final assembly.

Deburr the inboard and outboard edges of the A-1202A & A-1202B Inbd & Outbd Flaperon Skins. Deburr the aft edges, upper and lower, of the A-1201B & A1201C Inbd, Mid, & Outbd Nose Skins. Prime the A-1206 Pivot Brackets and A-1207-L & -R Actuation Brackets. If desired, all other flaperon parts may be primed at this time.



This completes page 18-04 of Van's Aircraft plans. Next time will deal with final assembly of the flaperons for the RV-12 aircraft.

Vans Aircraft RV-12 Build, Section 18: Flaperon (part 2)

Today I spent most of the time deburring parts in preparation for build the RV-12's flaperons.However, there were a few other steps I accomplished

Reference: page 18-02, 180-3, 18-04; 1.5 hours

Step 3: Flute the flanges of the A1204-L & -R Outbd Nose Ribs and A-1210-L & -R inbd Nose Ribs at the locations shown in Figure 3 and 4 of the RV-12 plans. Flute the rib flanges so as to make the rib webs as straight as possible however it is not absolutely necessary for the ribs to be perfectly straight.

Builder's note: I ended up putting very deep flutes in the ribs to get them as straight as possible. This was done after I deburred the edges of the parts.



This completes page 18-02.

Reference page 18-03

Step 1: Cleco together the A-1203 Spar, A-1204-L & -R Outbd Nose Ribs, A-909 Aleron Counterbalance, and A-1201C-L Outbd Nose Skin.





Step 2: match-Drill #30 the most outboard hole and most inboard hole of the A-1201C-L Outbd Nose Skin into the A-909 Aileron Counterbalance. See "match-drill call-out in Figure 1 of the the RV-12 plans on page 18-03.

Builders' note: Stainless steel is very hard, used new bits while drilling and Boelube (which is sold by Van's Aircraft). I started with a #40 drill bit and then final drilled with the #30.





Reference page 18-04

Step 1: Break apart the A-1208 Brackets by removing the hatched areas shown.



After completing the above steps, I deburred, etched and alodined the parts for priming.