Saturday, December 10, 2011

Vans Aircraft RV-12 Build, Section 21: Mid Fuse Ribs & Bottom Skins (part 5)

Reference: page 21-10; 4.5 hours

This entry continues the construction of the RV-12's fuselage kit. It still doesn't look like an airplane, but it look less like a pile of unrelated parts! Good/Bad news about the compressor. I found the replacement part for the compressor, they will cost about half as much as a new air compressor, however they are more than a month out. So I opted for a new 60 gallon unit from Home Depot. It is an oil compressor and much quieter than my old oil-less unit.

Step 1: Carefully deburr the edges and holes of the F-1233A Control Column Mount Spacer and the F-1223B-L & -R Control column Mount Brackets so that the parts will fit together tightly.

Builder's note: Be very careful not the over deburr the holes! As the bearing need to fit tight. Also in the picture below you can see my center parts were slightly curved and needed to be straightend.

Step 2: Machine countersink the four holes surrounding the bearing holes in the Control Column Mount Brackets. Machine counter sink flush on the outboard sides of both brackets for double-flush rivets. Machine countersink the two sets of nutplate attach rivet holes in the sloped flanges (flush on top.)

Step 3: As shown in Figure 1 of Van's Aircraft plans on page 21-10, sandwich the bearing and the control Column Mount Spacer between the Control Column Mount brackets then rivet the parts together. The hole indicated in the spacer locates the top of the part.

Step 4: Separate the F-1203B Bulkhead Flange by removing the hatched area shown in figure 2 of the plans.

Step 5: Seperate the F=1203D Stub Spar Receptacle Support by removing the materil shown.

Step 6: Machine countersink all of the #40 nutplate attach rivet holes and the sic #30 holes in the areas indicated in the RV-12 plans. Machine countersink the #30 holes 120degree NOT the standard 100 Degree!

Step 7: As shown in Detail A of the RV-12 plans page 21-10, drill the four 1/8 inch holes to the sizes indicated and remove the hatched area from the 7/8 inch hole to make it completely circular. The hatched area can be removed by snipping between the small holes using wire cutters, then finishing with a round file.

Step 8: Rivet the F-1203B-L Bulkhead Flange to the left aft side of the Bulkhead. Repeat this step for the right side of the bulkhead using the F-1203B-R.

Step 9: File the curved recess of both F-1203C Stub Spar Receptacles (the bevel locates the top of the part) to closely fit the rounded mating ends of the Stub Spar Assemblies of both wings. Once filed, mark the parts so that they will be assembled on the side they were fitted to.

Step 10: Cleco the Stub Spar Receptacle and the Stub Spar Recepetacle Support to the Bulkhead as shown in Figure 5 of the plans. Rivet the parts together using the two rivets called-out. Final drill #30 any holes too tight to accept a rivet. Builder's note: On my parts that was all the holes! Repeat this step for the right side of the bulkhead.

That's it for today! This also completes all of the steps on page 21-10 for the RV-12.