Tailcone

Flight controls are finished for now, minus the fiberglass, so I'm pressing on with the tailcone.  I'm extremely intimidated by the fiberglass process, so I'll tackle that one later.

The tailcone is a lot of large pieces and came together surprisingly quickly.  Obviously I'm not priming, so that certainly was a huge time savings.  First up is the bulkheads and also the first few divergences in the plans between the tail dragger and tricycle gear.

One of the biggest challenges is finding enough space to get the dimpling done on the larger sections of the tailcone.  Once that's complete, sawhorses and a scrap table worked well for initial mock up of the bottom skin and the bulkheads.

 Reminder, buy extra clecos.  You will need them, as I did during this time of the build.

Some of the rivets in the aft bulkhead area are REALLY tough to reach and rivet cleanly.  At this point in the build I wasn't using any protective tape over the end of the rivet gun.  Although everything is structurally fine, the aesthetics on some of the manufactured heads leaves much to be desired.  There are also a few smilies, but nothing too bad.

I had help during the build, and he was generally pretty excited during the process.  You can see his sign of solidarity at this particular moment.



The plans called for temporary attachment of the vertical stabilizer so that some of the holes can be match drilled.  That also requires the placement of the horizontal stab, resulting in these few pictures.  It's pretty cliche in the builders communities, but "It's really starting to look like an airplane!"

Tailcone completed.  Total time was 63 hours over about a month's time.

Elevators and Trim Tab

I felt like this is where the plans start to get more difficult.  I've definitely built up my skills at this point, but leafing through this section was a little intimidating at first.  Fortunately, nothing that I'm about to do hasn't already been accomplished and documented by hundreds of other builders.  The forums are beyond helpful.

Once the substructure was complete, it was time to dimple both skins.  I got in a rush and didn't have one skin settled on the dimple die properly and went through the skin slightly offset from the factory hole, resulting in a tear.  It was too close to the original placement to warrant a new rivet, but too far offset to drill out for an oops rivet.  In the end, I consulted with Vans and they said a new skin was probably the safest bet.  It was a blessing in disguise, as I have used that skin for scrap on other projects along the way (e.g. fiberglass forms).  

Once I had the replacement skin, I continued with mock up, disassembly and deburring.  I used blue painters tape to protect the parts inside the skin that wouldn't be in contact with the fuel tank sealant used to secure the foam ribs.

Once both sides of the skin are sandwiched together, the plans call for pop rivets toward the trailing edge to keep the ribs together.  This was a real pain, figuratively and literally.  There's very little room to work and using the pop riveter was tough on the hands/wrists.

Once the foam ribs are in place and secured with fuel tank sealant, both sides need to be clamped together.  I found that clecoes, spare lumber and woodworking clamps worked well for both trailing edges as well as the trim tab.

Once I was ready to rivet the trailing edge, the dimple die set pictured below was a huge win.  It's angled perfectly for the RV-14 trailing edge angles and made that part of the process a breeze with near perfect results.

Rolling the leading edges was identical to the rudder rolling.  However, I found out later that once the elevators were attached to the Horizontal Stab that the rolled edge was rubbing against the rear spar of the HS.  I found that a perfectly rounded edge wouldn't work.  I had to remove the elevators and flatten the area closest to the pop rivets on the rolled edge.  It took quite a few assemblies to get this right where I felt like I had flight control travel called for in the plans.

I attached packing tape or duct tape to different size dowels/pipe to get the desired curvature along the leading edges of the elevators as well as the rudder.  I then used downward pressure (toward the table) and rolled the edge toward the trailing edge with one hand on each vice grip.  Once I ran out of space to rotate the edge, I then released and reattached the vice grips to give me more authority to roll the edge.  Seemed to work fine until I determined that the rolled edge that allowed me to cleco and rivet top and bottom together still wasn't quite right to provide clearance from the HS.

Total time invested in the elevators and trim tab came out to about 48 hours.

Horizontal Stab

Time to start working on the horizontal stabilizer.  Lots of work to do on the front and rear spars making sure they're riveted per plans.  I messed up the countersink for one of the 4-5 rivets.  Always check your tooling before drilling away.  I ended up drilling out to a larger 5-5 flush rivet because I figured more strength probably won't hurt here.

Spars are complete, now time to prep the HS nose ribs and dimple the two skins.  The DRDT-2 got the job done, but it required an extra set of hands to spread the skins apart to get some of the dimpling done.  For the holes closest to the nose of the HS, I ended up using the pop rivet dimpling tool provided by Cleaveland.

The plans now tell you to make some stands that will hold the HS in place for follow-on assembly.  I used 1/4" plywood and 2x4s for the bases.  I cut the plywood with a jigsaw to get the initial shape and then made some final adjustments with the oscillating spindle sander to get the final form so there weren't any pressure points.  Make sure you have plenty of space and think through the riveting on both sides of the HS.  I have my EAA tables up against a wall in the garage, so I had to flip the HS around to get to the other side.  It would have been easier to move the tables to the middle of the garage to have access to both sides.

HS complete.  Total time was 34 hours.  I don't know why I took off the vinyl, but man it looks good without it.  Can't wait to see this shiny bird assembled down the road.