Rudder Lower Fairing
Posted: June 25, 2020
June 25, 2020 – I worked on the lower rudder fairing some more.
The leading edge of this thing has been giving me fits.
Even when I built up the leading edge, by the time I sanded it smooth, the material in front of the rudder horns was paper thin.
So I bent the tabs of the rudder in just a bit to make some room, then I mixed some more resin with flox and caked it inside the fairing at that point. With the fairing in place, it just fills the gap. When it was set up, I removed it all and sanded to smooth it. It fits much better now.
Time to move on. I hate fiberglass.
Posted: May 29, 2020
May 29, 2020 – I’m finally satisfied with my tail fairing.
Here’s the original stock tail fairing with the “ears” that go down behind the horizontals. I’ve had a lot of trouble with this partially because I tore the left side and repaired it. (This is actually a picture from when I back-drilled holes into my new solution, but more on that later…)
There’s an RV-14 in my hangar that I walk by every day. I looked at the tail fairings on it, and I thought I’d try to reproduce them. I bought a 2×4 sheet of .025 T3 from Spruce, and a piece of poster board.
I used the fairings and the inspection panel as a unit, and roughly traced the outline onto the poster board.
I cut this out and tried to secure it in place on one side. As long as it was close…I knew I’d cut the aluminum large and final-fit.
I back-drilled the holes from the original metal lower fairing, and screwed the new piece in place. Then I put the fiberglass fairing over the top and back-drilled the remaining holes. That’s the first picture I showed you:
I also marked all the trim lines to have the edges all aligned and clean.
The inspection panels will be under the new fairing. If I need to remove one of these panels, I just remove the screws on the inspection panel and slide it out from under the fairing.
The last step was to joggle the fairing because the fairing does not sit flat against the fuselage skin. This is on the RV-14 fairing as well. I drew bend lines and put in gentle bends on a small brake in the hangar.
Once I did the left side I stopped for the day. I came back the next morning and did the right side. The first one took 3 hours; the next one only took about an hour to make.
The last thing I had to do was cut the “ears” off the fiberglass fairing. There’s a screw hole right in line with the trailing edge of the stabilizer, so I drew an angled line swept aft. That gives it a more sleek look.
Here’s the metal fairing in place (before final trimming). I’m really proud of this:
Continued Tail Fairings
Posted: May 8, 2020
May 8, 2020 – I continued on all the fairings for the tail.
Fill and sand…fill and sand…fill and sand…
At this point, I’m getting to where I’m happy enough with the fairings that it will fly. They’re surely not paint ready, but I don’t have the patience nor the expertise right now to get them absolutely perfect.
Here’s the tail wrap-around fairing:
I installed the nutplates for the fairing, until I ran out… I did order nutplate jigs from the Yard Store for #6 nutplates. I can’t stand doing nutplate holes from a nutplate. Way too much error. More nutplates on the way from Spruce.
I did the elevator tips. They don’t require any major fitting.
I also installed the nutplates for the side inspection panels in the tailcone. I’m working toward installing the rudder and elevators permanently, so I’m addressing anything back there where they might get in the way. Here’s a nice shot showing the inside AND the outside:
Continued Tail Fairings
Posted: April 11, 2020
April 10, 2020 – I continued with the fairing for the vertical stabilizer.
I had to force the fairing into position, then I drilled the pilot holes for the screws. The right side does not pull down as far in the back, so I have to extend that part just a little bit.
I’ve also been working on the upper fairing as well as the tips for the elevators. No current pictures of those.
Continued Tail Fairings
Posted: April 4, 2020
April 4, 2020 – I continued work on the fairings for the tail.
I decided to enclose the elevator tips and make the cap wrap around the lead weight in the front. So I taped off the weights to keep the resin from sticking, and I wrapped cloth around the front. I also taped along the edge and filled there to smooth the transition between the elevator skins and the fairings.
Well, when I went to sand the ends, it was too thin. I also couldn’t remove the fairings… 🙁
So I decided to install them in place, and just use filler to fair out around the weights. Haven’t gotten to sand them yet. Hopefully this will work.
I moved on to the top of the vertical. I had previously made a foam plug to close the open end that faces the rudder. I hung the rudder back in place, and had to remove some material from the small vertical fairing for clearance. There’s a nice gap there now. I just have to seal the foam where material was removed, then fill the front of the rudder where the weight and the rudder skin are mismatched.
Then I moved to the fairing that wraps around the vertical and the horizontal stabs. I looked at the lower fairings, just flat pieces of aluminum that close the space under the horizontals. This is screwed in place into the longeron. So I removed the appropriate rivets, drilled up to #36, and tapped the holes for 6-32 screws. I also trimmed the tops of the fairings to give space for the rubber seal that will go there.
The top fairing fits OK. I wanted to get the front parts of this fairing fairly tight against the leading edges of the horizontal stabs, so the fairing twists a little bit when forced into that position. I’m backing off and thinking about how best to deal with this.
Category: RV-7, Empennage, Horizontal Stabilizer, Vertical Stabilizer, Fairings
Posted: March 12, 2020
March 12, 2020 – I started working on the fairings for the tail surfaces.
The fairing for the top of the rudder is probably the easiest fiberglass piece on the airplane. I just had to cut the fairing to clear the wedge in the trailing edge of the rudder. The rest was easy.
I then hung the rudder to check the clearance and position of the vertical stab top fairing.
Here’s the fairing in position.
Once I got the pilot holes drilled, I removed the fairing and glassed in a plug to close the backside.
I moved on to the elevator tip fairings. More or less the same as the rudder fairing. I cut slots for the lead counterweights, and fit and drilled the fairings.
Continued Work on Rudder Lower Fairing
Posted: March 6, 2020
March 6, 2020 – I continued the lower fairing on the rudder to prepare for the installation of the tail light.
I drilled the new screw holes to mount the fairing. The holes you see in this picture are the old ones, and they are filled with resin, so no worries about edge distance.
I installed the nutplates in the rudder.
I installed the chassis ground for the light. Not a lot of room in there. Hopefully this will be adequate. I removed one of the pop rivets and put a screw in its place, with a terminal on the inside.
Here’s a test fit of the light.
Continued Lower Rudder Fairing
Posted: February 6, 2020
February 6, 2020 – I stated on my previous post about the fairing that I had a couple of issues with its fit.
The light contour and the attach plate are bigger than the molded area the light attaches to. I’ll just build that area up to make a smooth transition.
I figured out that the fairing is now not vertically aligned with the rudder. I sighted up along the rudder trailing edge, and the fairing doglegs off to one side. Hopefully cutting the offending side at the screw holes will bring it back into alignment…
First, the misalignment.
Here’s a picture, best I could get, of the misalignment:
It’s kind of hard to tell, but it’s there. I cut a bit of material off the top on the right side, to hopefully pull the fairing towards the centerline when screws are installed. I filled the existing pilot holes for the screws, and I’ll redrill new holes when everything else is set.
Then I started working on fairing the light a bit better. I mixed a batch of resin and flox, and slathered it around the base plate for the light, as well as gluing the plate to the fairing. After it cured, the first sanding went pretty well. I just have to do the usual fill and sand…fill and sand… I also installed four pop rivets in the base plate to help to mechanically secure it.
Started Rudder Lower Fairing
Posted: February 2, 2020
February 2, 2020 – I started the lower fairing for the rudder that will also hold the tail strobe.
The fairing that comes from Vans was two pieces that they put together. They provide scribe lines on the part that are suggested cut lines. I know from experience that these lines are just guidelines, and that you should do your own fitting.
The first consideration is that the fairing needs to clear the tailwheel spring. I cut about 3/8″ off the top to give the fairing a 1/4″ clearance above the spring. You also have to make cuts to clear the control arm for the rudder.
I also needed to cut the front of the fairing to give clearance for access to the lower hinge bolt.
Then I trimmed the top to allow the fairing to fit along the lower edges of the rudder, where the fairing will attach.
I drilled screw holes through the fairing and the attach flange on the rudder. I’m going to use #6 screws and nutplates, since I want the fairing to be removable for the light.
This all sounds pretty easy, doesn’t it?
Well, when I got the fairing fitted, I found that the trailing edge of the fairing was mismatched with the trailing edge of the rudder by about 1/4″.
I figured the easiect way to fix this would be to split the trailing edge of the fairing, remove material from the pulled side, then resin the fairing back together.
It took two iterations of this process to get the fairing aligned.
In the meantime, I made an adapter plate to attach the light to the fairing. The plate is 1/8″ aluminum, made to match the contours of the light. I drilled and tapped the screw holes to directly attach the light. I had to chamfer the edge of the hole where it meets the back side of the light housing.
Still not done. Two problems…
- The light contour and the attach plate are bigger than the molded area the light attaches to. I’ll just build that area up to make a smooth transition.
- I figured out that the fairing is now not vertically aligned with the rudder. I sighted up along the rudder trailing edge, and the fairing doglegs off to one side. Hopefully cutting the offending side at the screw holes will bring it back into alignment…