Riveting Holiday fun & Tailcone complete (For now)

Page 10-20

Riveting

Looking at page 10-20 (shown above) of the plans I knew this was going to be a time-consuming process.  I anticipated about 15 hours to do and I was fairly close to that.  It's hard to determine exactly since I spent some time and focus on rematch drilling, priming and painting the Aft Deck, brackets, spacers, etc.  I was very methodical about this fix to ensure it's done perfectly, will show some pictures later.

My original idea on riveting was to back rivet the entire thing.  I have read about people doing that with some success and it seemed like a good idea.  I started out doing this, but I had some issues early on with the j-stiffener (F-1047) pieces and the bottom skin where the back plate wasn't at the correct angle and caused some skin dents.  There are specifically 4 rivets on the bottom that I'm not particularly happy with.  I went ahead and ordered some Oops Rivets from Vans.  These are in essence larger size 4 shanks but the 426 countersunk head is the same as the size 3 rivets.  My plan is to drill out the rivets with a #40 bit and then use the #30 reamer to enlarge the hole.  After that I will use a small block of wood, hammer and some dimple dies to get everything "flatish" and then rerivet.  And since I used rattle can paint I can paint over any inside scuffs fairly easy.

Since I was primarily working by myself I had to back rivet most the bottom.  When I got to the forward ends I was able to use a gun and bucking bar to do them.  Process is always the same, set 4 or so rivets in, tape over and drive each rivet ensuring the bar and gun stay in place.  The tape helps with scuffing or rivets shifting around.  I followed the directions minus riveting above the top j-stiffener since I will need to remove the new longerons to countersink later.  I chose not to do this after I match drill since I had to redrill the aft deck.  Didn't want to introduce any new variable that could cause something not to sit right.  Should also mention I didn't dimple the top row of the side sinks either for the same reason.

Bottom Rivets

After the bottom was riveted I moved onto the bulk head flanges with a gun and bar.  Again, working four at a time and alternating sides to get everything set in place at the same time.  I'm not sure if it would matter if you one side completely first and then the other... but didn't want to risk anything.  I also started with the middle bulkhead.

After that it was just a series of riveting different things at different times per the plans.  The sides were almost primarily buck riveted.  There are a few towards the end where you are able to use the pneumatic squeezer though.

In progress picture

Bottom again

Finished Tail

Page 10-21 is putting together the Bellcrank Rib assemblies and then riveting those into the tailcone.  The biggest challenge of this was actually riveting them inside the tailcone.  I decided to use the gun and a bucking bar for this step.  My arms were just long enough to drive the rivet from the outside while holding the bar in the inside.  Gravity helped a bit and while riveting I was resting the bar on the rib itself, so I could use two fingers to hold it in place.  As with all the steps you don't mess with anything that involved the front rib (F-1006).  All that will get dealt with when you tie the tail to the fuselage.

At this point I was done with riveting until I could complete a few steps with the longerons. But before I could work with that I had to redrill the Aft deck.  This involved Cleco'ing the tops back in place for rigidity and much like previously use paper to catch all the shaving inside.  I used a number of clamps and a level to make sure nothing was out of alignment and match drilled away, clecoing as I went.

F-1011D

This piece caused me some severe anxiety! This was the part that I didn't do correctly the first time around and ended up having to replace a total of 6 pieces.  I'm happy to announce it worked out great and I'll not have to worry about it again.  Also, the bonus as I mentioned before is I think my longerons fit better this go around then they did before... could just be that I'm being an optimist though.

Left- Old Bracket... Right - New Bracket

Triple checking longeron coverage

Really locked this piece down prior to drilling

Final result

Finishing up

I spent a few hours Christmas day removing the longerons and brackets to prime.  It was in the 60s and we had cold and rainy weather in the forecast, so this was really my only chance to get this done.  Prior to doing that however I had to countersink the 3/32 holes on the longerons and a few other minor items.  Everything worked fine, and I was even able to top coat with some rattle can paint later in the evening.

This officially retires my homemade empennage box paint booth.  This thing worked out great, small pieces I put on the wire mesh, larger pieces I set on top and if I had a lot of pieces just laid some cardboard out and set them in the middle section.  Since I'm doing QB Wings & Fuselage that get primer washed at the factory I won't be applying AKZO to anymore extremely large pieces.  For the remaining smaller pieces I plan to use the rest of the AKZO then switch to a rattle can primer and do it all on some cardboard.

Before

After

Even though the new parts were fully cured I decided to move forward.  Since there was little chance of things getting scratched it wasn't much of an issue.  Once everything was cleco'd in place it was just a matter of riveting the various rivets of the aft section.  I went longer on the spacer section since I added some depth to that piece.  Instead of using -8 rivets I used -9 which measured out correctly per my rivet gauge.

Really the most challenging part of finishing the aft section and the bell-crank assembly was finding the right hardware.  I had to use my go to reference book and micrometer to measure the bolts out.  It didn't specifically state in the plans, but I did go area and torque everything out to the proper Inch Pounds for the bolts; 25 for AN3 and 50 for AN4.

Aft Deck

Battery / Bellcrank assembly

Close to 200 hours into the project and I have all the empennage pieces completed.  I won't rivet the tailcone tops till I'm close to being complete, not wanting to crawl inside the tail cone if I can avoid it. 

I feel like I'm making good pace and with about 3 months before I get my QB Kits I don't feel rushed on the build at all.  Prior to assembling all the parts into an actual empennage I would like an EAA Tech Counselor inspect all the pieces. I'm sure given what I've learned over the last four months there are areas and rivets that need some attention.

Neato!