Just About Ready to Install the Fuel System

Did not spend much time on the project but spent a bit of time learning to use the tubing tools. One of our Chapter 75, tech counselors, Terry, came this morning and we reviewed the proper use of the tubing bending and flaring tools.

As I had purchased 6 feet of 3/8" aluminum tubing from the hardware store, I spent a few hours practicing before using the tubing supplied in the kit. As the tubing bender I borrowed from the club did come with instructions, looked on the net, found some and once I learned to use the "L", "R" and 45 degree mark on the tool, bending tubing became relatively easy. Using the hardware store tubing I was able to bend the first piece. As others have mentioned, it is not possible to get the 1st 90 degree as close to the flare as per the drawing. Following the words in the plans, it has you make this first bend as close as possible. As such the piece of tube downstream of the 2nd 90 degree bend have to be lengthened an appropriate amount. Also, the piece of tubing required was about 26.5" and not 24".

The only thing I did with the project was to install the systems blocks and move the fuselage to a set of sawhorses. They are normally installed in Section 27. That was one section I skipped to get the fuel system installed before I attach the tailcone. Don't drill the system blocks to 5/16" in one step. Gradually work your way to 5/16" a small bit at a time. Otherwise you will find the block spinning at the end of a drill bit after it is ripped out of your hand.

The sawhorses purchased at Harbor Freight were shortened to 24" by shortening each leg. 20" would have been perfect, but, this will do.

Time Today - 1 hour

Completed Section 26 - Seat Backs

I skipped Section 25, Tailcone Attachment and completed Section 26. The plane now has seats!! There is a lot of edge finishing and deburring to complete here. I primed to seat back rails.

The plans are very good, but, the drawings will play tricks on you. Perspectives! Ensure you study Page 25-01 and compare it with the drawings on the other pages in the section as you assemble. My foray into the Fuel Lines and Fuel System starts on Saturday.

BTW, my Harbor Freight sawhorses were too high. Cut 6" off each of the legs.

Time Today - 6 hours

Section 24 Complete - Baggage Bulkhead and Roll Bar Installed

Completed Section 24 in the plans without any incidents. The plans seem to be accurate and complete, so have no suggestions.

Installed the roll bar and riveted it to the fuselage. Prepped the baggage bulkhead and attached the multitude of nutplates. If you like nutplates, you will love the RV-12. Riveted the baggage bulkhead to the fuselage. Instead of first attaching the roll bar and then countersinking it, I countersunk it on the bench and then installed it. Countersinking while standing on a ladder is not for me. Riveted it it place. Don't know if it was wise to paint the rollbar. It may get scratched and require a bit of touch-up, especially on the outer surface. Time will tell.

Lots of different types of rivets are used here. Pay attention to the plans.

Bought a set of shorty metal folding sawhorses at Harbor Freight. They were cheaper than buying brackets and 2x4's. The project will soon leave the standard work table, as it is much too high. Section 25 has one attach the tailcone. Think I will first build the seatbacks and then install the fuel lines. Then, maybe, attach the tailcone before interior paint. Still have to decide on the paint type and color. Thinking textured or hammered, most likely in a flat gray tone.

Time Today - 5 hours

Do You Believe I am into Final Paint

Yesterday, I visited John Bender in Jesup, IA. He is also building the 12 and is finished with the wings, tailcone and fuselage. I observed John painting the interior of his RV-12 and wanted to pick up a few tips. His project is marvelous!! The brown stone finish looks very good. Mine will be grey. When I got back home, finished the day by deburring a few parts.

Today, I am into FINAL paint. Decided to paint the roll bar, the roll bar brace and the roll bar brackets after visiting John.

Probably spent about 6 hours today on the project, there is a lot of waiting for the primer, top coat and clear coat to dry. (Read the instructions on the cans.)

I first match drilled the roll bar bases, then removed the roll bar from the bases and removed the bases. Sanded the exterior of the roll bar ensuring all rivets were flush with the top surface of the roll bar (do not want to scratch the rear window). Primed the roll bar bases with Marhyde. Built a couple of stands to hold the roll bar for paint. Got the paint I would need from WalMart. As my fuselage will be white and did not want any glare, I chose Marhyde primer, a flat white and a flat clearcoat over the base coat. Painted the roll bar, the roll bar brace and the roll bar brackets. My first paint experience. NO runs!! All will sit until the next day.

Time Today - 6 hours

Roll Bar Installed - But it Has to Come Off

Quite a bit of progress. Let me see if I can remember. Renee and I trial fitted the roll bar to the roll bar bases one more time. Took a width measurement. Removed the roll bar from the fuselage and took a measurement, IT CHANGED!!! It was 3/16" to 1/4" less. It had shifted inward. Based on the input from the forums, I decided to reattach the roll bar, take a final width measurement and then use a scrap piece of 2x2, acting as a spreader to ensure the width did not change after removal and as I riveted all of the pieces together. See the pictures.

I first riveted both sides of the roll bar to the roll bar plates, thinking that this would help maintain the width. Then clamped the assembly flat on the top of workbench. Read in the forums that warping had been an issue with at least one builder. When finished riveting, the width was perfect and there was no warping.

Was a bit difficult to cleco the roll bar to the base but got it done. Think I may have to touch drill some of these holes!! Reading ahead, all has to be disassembled for priming! Oh Well!!!!

UPDATE: Suggest painting the final color of the underside of the F-1254-L and R now with the color of your choice. I chose the canopy deck color. Also, it is time to paint the underside of the Mid Fuselage Brace.

Time Today - 8 hours

EAA Open House, 2nd Tech Inspection and Start of Section 24, Roll Bar

Today I hosted an Open House for our EAA Chapter, Chapter 75. Had about 30 guests view the project from 2-4PM. All were impressed with the RV-12. At the same time had my 2nd Technical Inspection by Jim, one of our chapter Tech Counselors.

After the open house, started deburring the parts for the roll bar. Cleco'd it all together and then tried to trial fit it to the roll bar base temporarily attached to the fuselage. The width of the roll bar was perfect but it would not slide down onto the base unless I used way to much force. I disassembled all and checked the angle of the roll bar flanges where they insert into the base. The angles were a bit short of 90 degrees. Opened the angle on the four roll bars just a bit. Reassembled all (sure are at lot of 3/32" clecos) and then tried to trial fit it again. This time is slid on halfway with just a little push.

One thing I noticed was an uneven surface on the top of the roll bar flange. Thanks, Larry! There were deformations around each hole in the surface. Used a sanding block to remove the majority of the imperfections.

I don't think the tool list includes the required number of 3/32" clecos. I had them, you will need a number of them. Next step is to match drill each hole to #30 and then countersink all of the holes in the top flanges using a #30 x 120 degree countersink for a CS4-4 rivet.

Time Today - 4 hours

Air Conditioning Installed

Installed the highly efficient RV-12 air conditioner today. No problems, though it took some time to debur, countersink and then rivet all of the parts for the vent. Then on to the cowling hinges. On the advice of the VAF forums, I cut the hinge to 10.5". BUT then I cut off the wrong tab on the end of the hinge. This was totally my mistake. It is sure so easy to get turned around when looking at the plans, then the plane. I am now a charter member of the "Buy Some More Hinge Club". Can't wait until I become a member of the "Buy Some More Fuel Line Club".

Cut another piece of hinge and cut off the correct tab. Match drilled it after postioning. Ensure the bottom firewall does not move as you have to remove all clecos and then clamp all into position before match drilling. Primed the hinges and the spacer. Let them dry for about an hour and then riveted the hinges to the firewall bottom.

BTW, after looking at the pictures, got that last rivet!!!!!!

Going to have an EAA Chapter 75 OPEN House on Sunday to allow all of our club members and any other interested to view the project. Hope to get a critical EAA Tech Inspection at the same time. It is time for the 2nd inspection.

Time Today - 5 hours Totals-137 Hours on the Fuselage - 108 Hours on the Empennage (85% Complete), 175 Hours on the Wings (100% Complete)

Longerons Complete, Side Skins Riveted

UPDATE: I did not have the tubing tools to do this now but there was a very good suggestion on the VAF forums. It was to install the Fuel System in Section 28 of the plans prior to attaching the side skins. Without the skins it would be a lot easier to access the tunnel.

UPDATE: See my blog entry for March 26. Prior to riveting the side skins ensure a nutplate at the forward part of the side skins is correctly dimpled. The plans are in error here.

Cleco'd the left and right side skins to the fuselage and riveted both of them paying attention to the note on the drawing that says "Do Not Rivet Here". All of the holes matched very well. Did NOT have to touch drill any of the holes. Section 23 in the plans will be history after Saturday. Am going to run out of things to do. Glad the finishing kit was announced today.

Time - 6 hours

Longerons, Longerons

Continued with the longerons today. Today I first checked the aft angle of both of the longerons before proceeding. The left and right longeron were bent 3.8 degrees inboard per the digital level so I was satisfied to continue.

Then recleco'd the skin and the longeron to the fuselage. Took a bit of time, lots of clecos. Drilling of the longeron proceeded without any problems. Did the same for the other skin. Removed all of the clecos and then started to debur all of the parts. Lots of holes here and deburring each of them took quite a bit of time.

ONE CAUTION: When drilling thru the F-1205A, roll bar attach plates thru the longeron and then thru F-1204F Aft Side Bulkheads, try and position the holes in the aft side bulkhead directly under the hole in roll bar attach plates. If I did this again I would proceed as follows. With the longeron NOT installed, cleco the roll bar attach plate to the aft side bulkhead. With a Sharpie, trace the top of the aft side bulkhead onto the bottom of the roll bar attach plate and extend the marks to the outboard edge of the plate. After installing the longeron and before drilling the two holes, ensure the aft side bulkhead is positioned within your marks.

After deburring, removed all of the machining marks from the longerons, scotchbrited them, cleaned them with acetone and then primed them using Marhyde. Had to open the garage door a bit, lots of fumes. It is 20 degrees outside today!!!

Then, prepped the side skins by cutting off the aft tabs, finished the edges and then attached the nutplates for the opening. Step 5 on 23-06 indicates we are supposed to dimple the nutplate holes around the triangular opening of the side skins flush with the INBOARD side. This is incorrect. They should be installed flush on the outboard side. The nutplates go inside the fuselage per an e-mail from Van's. Did not have any problems dimpling as I had the smaller yoke for the squeezer. The rivet holes AND the holes on the nutplates have to be dimpled.

Broke the bottom and aft edge of skins per the instructions using the Cleaveland edge braking tool that looks like a set of vise-grips. Made 3 passes. Gave me a consistent edge. Riveting of all of these components will have to wait for Friday.

Time - 8 hours

Will Drill the Longerons Tomarrow

Had another good day! A lot of deburring. Installed all on Page 23-04 without any problems. Things looked a bit weird so I trial fitted the left and right skin to the fuselage. All of the holes matched so I disassembled all and then continued. Removed all of the machining marks from the edges on the skins. Then had to cut the holes for the wings in the fuselage side skins. Used drills, the unibit, snips, the dremel tool with a cut off disk and had to file to the line quite a bit with the multitude of files in the toolchest. The Vixen file was a godsend. Took quite a bit of time but the result is very, very acceptable. Page 23-06 Step 1 took me for a loop. I tried and tried again to figure how to attach the F-1202L gussets. Perspectives on the plans are strange at times. Had to look forward in the plans to Page 29-03. The perspective here was much clearer. It should be installed correctly.

Will match drill the longeron tomorrow.

Time - 7 hours

Completed Bending the Longerons and More

It was a very good day at the airplane factory. Completed the left and right longeron. Whew!!! Happy that fabrication process is complete.

Today I made some final tweaks to the right longeron using the template. After I was finally satisfied with the match, I had to bend the aft end of both 4 degrees inboard in accordance with the plans. Had to use the 5# dead blow hammer to get the angle to budge. You have to whack it pretty hard. Using a little bit of high school trig, 4 degrees equates to a tad less than 7/16" over 6 inches. (Remember, Tan 4 degrees = opposite side/adjacent side of 6"). Using a straightedge and a small ruler was all that was needed. See the picture. After bending the initial 4 degrees inboard checked the vertical and discovered the angle needed to be beat back into the vertical plane. Used the dead blow hammer again. After a couple of iterations, finally ended up with a 4 degree bend and a flat top longeron surface. I did not trim the aft end of the longeron for weight savings. (Maybe later??)

Match drilling of the longeron to the template went very well. If you match the template during the bend process, this step will be easy!

Onto page 23-03, deburred all of the parts and MCS then riveted the roll bar attach plates, the mid fuselage brace and the mid fuselage brace closeout to the fuselage. I placed F-1205C over F-1205A on the forward edge of F-1205C. The plans do not specify if F-1205C should go over or under F-1205A on this forward edge.

Found a 2nd error on Page 23-03. The plans tell you the MCS the F1205B Roll Bar Attach plate, #30-120 degrees in 4 locations on its forward edge. These 4 locations get a CS4-4 rivet (Figure 2, inset). Appears that the 5th hole on the forward edge needs to be MCS also. See Page 23-06, Figure 1. The forward, outboard hole gets a CS4-4 rivet here.

A good day!!

Time - 6 hours