RV-12 Rudder (Finishing)

Reference: page 07-03, page 07-04, page 07-05; 3.5 hours

Today the rudder for the RV-12 will be completed. If you are just joining this blog I'm in the process of building a Vans Aircraft RV-12 airplane that fits in the E-LSA (Experimental Light Sport) Category. The idea is to follow through the builders manual and document each step with pictures. If you look at the Topics on the left you can reference a specific page of the plans. You will also information about my RV-10 as well.

Let's see, we left off after checking the Hinge spacing for fitting the rudder spar to the vertical stabilizer. The parts have been alodined and primed with zinc chromate primer.



Reference page 07-03

Step 2:


Remove the R-1205 Hinge Brackets and WD-1205 Rudder Horn. Rivet the R-1204 Spar Caps and the R-1203 Main Rib to the R-1202 Spar. Rivet only the four holes common to the main rib. See the rivet call-out in Figure 2. NOTE: On my kit these rivets were a half size too long (this makes the shop head want to "clinch" or go off side ways) so I ended up cutting them down to size before setting them. Your mileage may vary;)



Step 3: Rivet the R-1205 Hinge Brackets to the R-1204 Spar Caps and R-1202 Spar. Rivet the remaining holes in the spar caps to the spar. See the rivet call-outs in Figure 2. NOTE: I found it easier to set the rivets I'm pointing at in the picture below before installing the hinge.





Step 4: Completed on previous blog entry.

Reference: page 07-04

Step 1: Rivet the R-1203A. trimmed Rib to the WD-1205 Rudder Horn. Flange orientation and rivet call-outs are shown in Figure 1. Refer to this assembly as the Rudder Horn Assembly. NOTE: Not sure if the two LP4-3 should be installed from the top or bottom, so I installed them from the top as it was a much better clearance for the rivet puller.



Step 2: Rivet the Rudder Horn Assembly to the R--1202 Spar, as shown in Figure 2.



Step 3: Rivet the three remaining R-1203 Main Ribs to the R-1202 Spar. Flange orientation and rivet call-outs are shown in Figure 3> Refer to this assembly as the Rudder Skeleton Assembly.



This completes page 07-04.

Reference: page 07-05

Step 1: Remove the material shown hatched from the lower end of the R-1201 Main Skin shown in Figure 1.



NOTE: I "broke" the leading edge of the left skin to help it lay flat and not pucker after riveting. This is not called for in the plans, just something I did.



Step 2: Position the R-1201 Main Skin oner the Rudder Assembly. Check for main skin hole alignment with the Rudder Skeleton Assembly. Cleco the entire main skin to the Rudder Skeleton AAssembly.



Step 3: Star nearest to the trailing edge rivet the R-1201 Main Skin to the Rudder Skeleton Assembly per call-oust in Figure 2. Leave open the top row of holes in the main skin.



Step 4: Close, and rivet the R-1201 Main Skin on the forward side of the R-1202 Spar. the main skin must overlap onto itself as shown in Figure 3.





This completes the rudder and section 07.

RV-12 Rudder

Reference: page 07-02, page 07-03; 4.5 hours

Today I'm starting the rudder on the RV-12 airplane.


Step1: Read all steps in manual prior to construction.

Step 2: Separate the R-1204 Spar Caps by removing the material shown hatched in Figure 1. Deburr all the edges of both caps.



Step 3: Mark both of the R-1204 Spar caps with a centerline on the surface that will nest against the R-1202 Spar web as show in Figure 3.



Step 4: Final-Drill #30 the 1/8 inch holes in the R-1205 Hinge Brackets as called out in Figure 2.



Step 5: Final-Drill #12 the 3/16 inch holes in the R-1205 Hinge Brackets as called out in Figure 2.



Step 6: Separate the R-1205 Hinge Brackets by removing the material shown hatched in Figure 2. Deburr all the edges and drilled holes of both hinge brackets.



Step 7: Position the R-1204 Spar Caps between the flanges of the R-1202 Spar so the center shows through the middle set of holes in the spar web as shown in Figure 3. Adjust the bend of each spar cap, as necessary, to nest against the inner surface of the spar web and flange as shown in Figure 3. Detail A-A.



Clamp the spar caps in place. Mark the spar caps left or right so they can be installed in the same position as drilled.



Step 8: Match-Drill #30 the holes from the R-1202 Spar into the R-1204 Spar Caps per call-out in Figure 3. Cleco each hole before drilling the next. First match-drill the holes in the spar web, unclamp and clear away any chips, cleco the spar caps back in place.





Then match-drill the holes in the spar flanges. Remove the spar caps, deburr holes, and clear away any chips.



Step 9: Final-Drill the holes in the WD-1205 Rudder Horn as shown in Figure 4.



Step 10: Cleco the R-1204 Spar Caps, the R-1205 Hinge Brackets and the WD-1205 Rudder HOrn to the R-1202 Spar. Position clecos on the web of the spar as shown in Figure 4. Hereafter refer to this assembly as thew Rudder Spar Assembly.



Reference: Page 07-03

Step 1: Check the rudder hinge alignment by temporarily attaching the Lower Hinge Assembly to the V-Stab Assembly. Temporarily attach the Rudder Assembly to the V-Stab Assembly as shown in Figure 1.

When installing the hinge hardware, use one washer between the bolt head and R-1205 Hinge Bracket, one washer between nut and hinge bracket, and only one washer between each hinge bracket and upper hinge assembly. Begin with the same hardware order for the Lower Hinge Assembly. AN960-10L Washers may be substituted for AN960-10 Washers to adjust clearance between the hinge brackets.

Once a fit is confirmed, make note of the washers used. Detach the Rudder Spar Assembly.

NOTE: I made some washer holders out of tongue depressors to make it easier to place the washers.









Step 4: Remove the forward flange from one R-1203 Main Rib, per dimension in Figure 3. Deburr the trimmed edge. Hereafter refer to this trimmed rib as the R-1203A Trimmed Rib.