Section 10 - Tailcone

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	Section Hours: 148.5	Section Status: Complete

October 21, 2006 (10-14 step 4): After another way-too-long break (lots of things going on right now!) I managed to slip out in the shop. 1st thing I did was match drill the 4 screw holes in each of the F-824 cover plates and skins. Plans call for a #28 drill but we don't have one that size. Since these are screw holes as opposed to rivet holes, and the difference in size between a #28 drill and a 9/64 is 1/10,000th I used the 9/64 bit I had. After that I dimpled the cover plates but not the skins yet... still need to debur those. These plate will cover the access holes in the skin to access the elevator horns.

(10-15 step 5): Next up I removed the upper & two sides to the F-1006 bulkheads and dimpled the common holes. These holes will get flush rivets because the rear baggage bulkhead will rest up against them. The lower piece in the pic is the baggage bulkhead channel. Since it mates to the upper portion of the F-1006 bulkhead it'll get flush rivets also.

(10-16 step 4): I then marked off all the holes not to dimple on the bulkhead and frame flanges and started dimpling as I checked each piece for scratches & deburred the holes. I've still got a few of the frames to go because they're still clecoed to the skins.

(10-15 steps 7-9): No real ryhme or reason today I guess… just whatever comes to mind. While I was dimpling the flanges on the F-1012A & B bulkheads I went ahead and dimpled all the web holes. While doing this I noticed the four #30 holes used to rivet the tie-down were only drilled to #40, so I had to redo those. Once the two rear bulkheads were all dimpled, I countersunk the mating holes in the tie-down and also the rudder stop brace. And finally I dimpled the flanges of the rudder stop skin stiffeners.

October 23, 2006 (10-16 step 1): Tonight I started off with a few minor things here and there. The main thing was I got all the skin holes on the longerons countersunk. There are a few that need to be skipped. These will be used to attach the empennage fairing with screws later.

October 26, 2006 (10-16 step 5): Grasping any opportunity I can to get in the garage right now, this morning before work I managed to get one of the tailcone stiffeners deburred and the holes dimpled. After work I managed to get three more done.

October 29, 2006 (10-16 step 5): Today we continued on with the stiffeners. We got 5 more done today. While deburring 2 of them we noticed these impressions. There are two pair and then a single one. Its pretty obvious they were made at the factory but I haven't noticed them until now. I sanded them down about as smooth as I could get them, but I still don't like them. I may have to have the tech counselor have a look at them.

November 2, 2006 (10-15 step 4): I decided to go ahead and remove the blue protective film on the outside of the tailcone skins just along the rivet lines. I moved away from this practice on the other skins for time reasons, but I'm doing it here because we'll be back riveting as much of the skin rivets as possible and unlike previous parts we've back riveted, the tailcone assembly will get pretty heavy, and moving it around on the table will cause any small aluminum shavings to cause some decent scratches in the skins... we know... we've already experienced them! So anyway, after that was done I deburred the outside of the holes on the left side skin. Also, evidentally when the longerons were being drilled some of the aluminum shavings were trapped under the blue film and caused some pretty good scratches around the holes. Normally I wouldn't worry about scratches (within reason) on the outside of the skins since they would be removed during paint prep... however, after dimpling and riveting these scratches would be hidden under the rivet heads. So, I used a roloc disc to sand them out, and since the alclad layer was now removed I followed that up with a quick brush from the alodine pen. You can see a couple of these holes at the top of the pic.

(10-15 step 3): After removing the right side skin it was time to trim the triangular portion from the front of it. The left and right side skins are identical to each other until the factory puts the bends in the bottom portions of them for the transition down to the belly skin. Then they become dedicated left and right parts. The triangular portion at the front of the skin fits under the lower rear of the baggage door, and there is only a baggage door on the left side of the plane. So, we get to cut this triangular portion from the right skin... ta-da!! He did it! Now that didn't hurt now did it...

(more 10-15 step 4): While I'm having all this fun Angela's been deburring bulkheads, ribs & stiffener holes. She's also got some stuff slow cooking on the stove and the smell is starting to make its way out into the garage… mmmmmm……

(and yet even more 10-15 step 4): Suffering through the smells ;-) I deburred all the holes on the outside of the right side skins before calling it a night.

November 3, 2006 (10-15 step 4): After a little stint of deburring tonight……

(10-17 steps 1 & 2): ...... I was looking for something a little different. So I decided to take care of the elevator bellcrank assembly. First thing was to fashion a small spacer from a piece of .063 sheet stock. I then drew a line down the center of it length wise. After that came the deburring (exactly what I was trying to get away from... but a necessary evil!) of the two bellcrank pieces. Then the two pieces were clecoed together sandwiching the bearing in between. The spacer was then slid in between the two bellcrank pieces and the line was centered in the holes. Keeping this line centered in the holes I made sure the spacer was centered side to side and then clamped the bellcrank pieces down on it to hold it in place while I match drilled the holes into the spacer. Here you can see the entire assembly clecoed together. This assembly is what will connect the push-pull tube from the flight controls to the push-pull tube going back to the elevators.

November 6, 2006 (10-15 step 4): For some reason I was all pumped up tonight about gettin'er done so I stayed up way past my bed time and deburred. Man we managed to put quite a few scratches in our bulkheads and skins during the pre-assembly. Nothing major but enough to feel with your fingernail so I've been sanding those out. Tedious but I feel better about it after its done. Getting closer to priming...

November 9, 2006 (10-17 step 3): Again looking for a break from deburring :-) I decided to scuff one of the skins in prep for priming. This is the aft top skin. I found a really cool idea on Tim Olson's site… one of those DUH's!!! I attached a scotch-brite pad on the bottom of my palm sander and scuffing the skin took all of about... oh, I don't know... 2min! One of those 'why didn't I think of that' moments. After that, I dimpled all the holes except for the five screw holes that will be used to attach the empennage gap fairing.

(10-15 step 4): After the skin its back to more deburring and parts prep for priming… bor-ring.

November 10, 2006 (10-16 step 3): Tonight I scuffed the tailcone belly skin, cleaned it up, and dimpled it. In addition to the interior portion I also scuffed the exterior portion where the side skins will overlap it. I'll shoot some primer on this area too.

Next up I scuffed the exterior portion of the side skins that'll be overlapped by the top skins. I ran the alodine pen over these so I probably won't shoot any primer on these.

November 11, 2006 (Rudder Cable Fairing Covers): We debated on how to put these on, which consequently dictates when we can put them on. These fairings give a more cosmetic look to the aft area of the rear fuselage where the rudder cables exit the side skins. Without them you would just see a plastic tube sticking out the side of the fuselage, so it's quite common for builders to add these to cover the tube and opening. Traditionally they are attached with just solid or pop rivets. Doing it this way means you have to install them after the rudder cables since the end piece on the rudder cable won't fit through the opening once they are installed. The rudder cables aren't installed until we get to the fuselage. We could wait, but we'd like to not use rivets in these guys incase we ever need to pull the rudder cables out for some reason... shouldn't have to but who knows. Anyway, I liked fellow RV-10 builder CJ's idea of attaching them with screws so Angela & I decided to go that route. Here you can see the covers... on the left is the way they came from Avery Tools (other suppliers carry them as well). On the right shows how I cut them down... just looks better in my opinion.

Next I eyeballed a centerline point on the front and rear portion of the cover. The pitch angle of the longerons on the side skins are parallel to the direction of flight, and the longitudinal axis of the rudder cable openings in the skins pretty much parallel this. So, I plan to line up the centerline of the covers parallel also. I measured down from the top edge of the side skins and drew a line through the center of the opening that parallels the longerons. After that I drew a perpendicular line along the rear edge of the opening, and then another ~1/4" behind that. This was used to locate the rear edge of the cover. I then marked 4 hole locations on the covers and drilled 3/32" pilot holes. After that I used the marks on the skins to clamp the covers in place and then finally match drilled the holes into the skins.

After that I pulled the covers off and drilled the mounting holes for the nutplates. The screw holes will get dimpled for #6 screws and the nutplate holes will get drilled for AD3 flush rivets. Now, hopefully we got the fore/aft position correct… but I'm not to worried about it, looks like is should workout ok.

(10-15 step 4): Just a little more Page 10-15 Step 4 left!!! Not too much deburring left… Finished deburring the left side skin...

(10-16 step 3): Next up I scuffed the inside of the skin and cleaned it. Now it was time to dimple the skins. Once these babies are done, it's time to prime!

November 13, 2006 (10-4 steps 1 & 2): As we were tearing down the remaining pieces of the tailcone the other day I noticed the #12 holes we drilled in the horizontal stabilizer attachment angle… they bugged me. They seemed way to close to the edge of the angle. I set it aside… but it kept bugging me. Well, since I had another piece of angle I decided to go ahead and cut another one. I cut this one about 1/4" longer thinking I'd sand the edges down to a perfect fit. I took my time making sure to get all the holes perfectly positioned... first I match drilled the frame holes using the existing angle to get the height just right. Once those holes were drilled and the angle was clecoed to the frame, I clecoed the assembly to the longerons, the aft deck, and the F-1010B spacer that goes between the angle and the aft deck. I then used a couple of #30 drill bits to line up the holes in the aft deck and spacer and then clamped these to the angle. Next I match drilled the four #30 holes of the aft deck into the angle.

(10-13 steps 3 & 4): After that I started to match drill the #12 holes that go through the longerons, but only drilled far enough to give a small dimple to use for positioning the #30 drill bit. After #30's were drilled through, then I opened the holes to #12. Here you can see the before and after result. As you can see, the #12 bolt hole is quite close to the edge on the first angle we did. The second attempt makes me feel a quite a bit better. The interesting thing is I didn't have to sand the new angle to fit like I originally intended... it fit just fine as is! A quarter inch longer (about an 1/8" longer than the plans call for) and it fits just fine!

November 15, 2006 (10-15 step 4): Ok… one last look at things in prep for alodine & priming… one thing about putting things on hold for periods of time (at least in our case), they tend to get moved around a lot. So even though I've gone over a lot of these parts before, I'm looking them over now and noticing nicks, dings, and scratches... grrrrrr!!! More 'deburring'! Oh well, guess that's an argument for not stopping huh... just get'er dun! I like that idea, and I think I'll have to try and focus more on it!

November 16, 2006 (10-17 step 3): Today I snuck out of the office a little early (late days the first three days of the week make it a bit easier!) My focus was to get started with the alodining. I've got all the smaller items wired-up to dunk in the buckets, so I made it a point to get those done. One thing to mention here... we originally took the frugal approach to alodining. We considered getting the powder and mixing it, but there was a minimum buy requirement that made it impractical, so we went the Alodine 1201 (premixed) route. It comes in 1 gal bottles (quart bottles also I think). According to the manufacturers sheet, for dipping parts the product gets diluted 1:2 with water (same with the alumiprep but its 1:3). I don't think we'll go this route again because it basically takes at least 10 minutes to get the job done, and this time is getting progressively longer, an indication the chemicals are "aging" and in need of replacement. I can do about 6-8 parts at a time in the buckets, but it still seems to take forever!! I think we'll just go full strength in the future, mainly due to the time, but even after all that time we're still not getting that deep gold color that it should be. One of the reasons we went the dilution route was because we needed the volume to cover parts in the buckets. Finding out that 1 gal of chemicals could be diluted to make 3 gal seemed to be perfect... but its winding up to be a time killer! We'll spend the extra $$ for a couple extra gallons next time to save the frustration!

November 17, 2006 (Tech Counselor Visit): This morning Martin & Claudia Sutter came by for our first tech counselor visit… very nice people! They have a long history with RVs and have built quite a few (I forget the exact number) including the older type kits that were not prepunched... now that's building an airplane! I have a lot of respect for anyone that's built one of those! Anyway, the EAA's tech counselor program is a wonderful deal! Totally voluntary, and they provide an invaluable service keeping newbies like Angela & I on the straight and narrow! I made it a point to bring up all the "questionable" items I could remember from the build (things like boogered up rivets, dents & dings, etc) and had Martin check them out... he said they were all very minor and nothing to worry about. I also picked his brain a bit on techniques for certain things (but thought of 20 more as soon as they left!) Overall the verdict was the quality of our build so far is definitely above average, and far exceeds anything in the production factories... Our family out there following the build should be very excited to hear that ;-) Here's the first of our Tech Counselor Visit Reports... We'll have at least 3 more of these before we're done with the plane.

(10-16 step 3): Now… back to work! Just before Martin & Claudia arrived I noticed we still had a few more dimples on the side skins to do. The rivet holes in the curved portion of the skins was a little difficult to do solo so I waited until Angela could help. I guess I had forgotten about them. So, we got 'em done before she sped off to work. She's supposed to be off today, but duty calls!

(10-17 step 3): Next up was to continue with alodining… Well… this stuff is difinitely OLD. I'm getting marginal results even leaving parts immersed for 10min… Let me tell you that gets reeeeaaallll boring when you can only do a couple at a time. Check out the contraption in the pic below. I glued an endcap on each of 2 pieces of 10'x2" pvc, clamped a couple of 2x4 blocks to the table to keep the tubes from rolling around, and them propped them up between the two tables. I then filled one with alumiprep, and the other with alodine to slide the longerons and stiffeners into. Doing two at a time this took forever! This is definitely the last job this batch-o-chemicals will be used for. I also found a couple of shallow 3'x18" plastic tubs to do the bublkheads in and originally I expected to get all the remaining parts done today... but the sun had other plans! Soooo, I've got just a few more parts to do tomorrow morning. Can't wait ;-)

November 18, 2006 (10-17 step 3): I started off the day by alodining the last few frame & bulkhead pieces. After that it was time to prime. Quite a bit more priming to do this time! I mixed up a full batch of primer for my gun, and then just before I started spraying I mixed up another full batch. I went through both (as expected) and then took a break as I mixed up a third batch. This time I only needed about 2/3 capacity in the gun. Turned out good, and this was definitely my best priming to date.

(10-18 step 1): With only a little time left before having to leave, I decided to use the pressure left in the compressor to hook up the squeezer and squeeze a few rivets! Here you can see the F-1012 A & B bulkheads with the rudder stop brace and tie down bar attached.

(10-18 step 3): Really not having the time to but what the hay… I clecoed together the F-1011 bulkhead assembly and for good measure attached the nutplates to the rudder cable angle. Uh-oh… time to go!

November 19, 2006 (10-18 step 2): First up, finish the F-1011 bulkhead that I started last night. I had planned on all my shop heads facing the same direction, but it turned out that the 4 rivets used to attach the bulkhead stiffener that are right next to the horizontal stabilizer attachment bars didn't have enough clearance to get the flush squeezer set in there. So those 4 are turned around the other direction... oh well, points off for my show plane ;-)

(10-19 step 2): Next up was the attaching the horizontal stabilizer attachment angle to the F-1010 bulhkhead.

While attaching the angle I noticed this crack in the bulkhead [sigh]… time for a bit of surgery. Once smoothed out, it was alodined.

(10-19 step 1): Now THIS is the sign of an excited woman! Hasn't even taken the time to get dressed yet and she's out in the garage wondering what she can do to help! Here she's dimpling the nutplates for the cover plates and the rudder cable fairings. Once done I helped her attach them to the side skins.

(10-19 step 4): Last thing we did was to quickly glue the rudder cable snap bushings into the Rudder cable bracket that'll get attached to the F-1008 frame.

Ok… I know I said "the last thing"… well, after getting home from work I wasn't quite ready for bed… or was it excitement about working on the plane ;-) Anyway… we decided to get back to it!

(10-21 step 1 & 2): Since it was late I was looking for things I could rivet with the squeezer and not disturb the neighbors with the rivet gun. Moving ahead in the plans I found I could take care of the bellcrank ribs and angles. I attached the nutplates to the angles, and then the angles to the ribs.

(10-20 step 1): Wanting to do just a bit more I started clecoing together the main assembly in preparation for riveting the skins.