Category: Elevators

July 15, 2010 – OK. I know I said before that the elevators were done, but I did have a couple of housekeeping items to take care of. I wanted to get a rough rig of the elevator trim servo with the tab.

Per the schematics that came with the Ray Allen servo kit, I wired everything together so that it would run. Using a 9-volt battery for testing, it all ran fine.

I discovered, as I guess most builders do, that I had to either bend the threaded rod or extend the cutout. There is interference with the cutout when the tab approaches full nose-up. I opted to extend the cutout about 1/4″ or so. Now the rod just clears at full nose-up.

Here’s a video of the tab running through its travel.

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I also removed the composite end rib from the elevator, since I wasn’t happy with its shape. It was slightly rounded on the top and the bottom. I sanded the top and the bottom until they were flat, then I reinstalled it, using sealant like I did before.

Time : 1:45

June 15, 2010 – I’m going to call the elevators finished. I have 2 months to wait before I see the wings, and all I really need to do on the elevators is to do a preliminary rig of the elevator trim servo. That’ll be a good job for the hot summer days ahead, since I can bring the left elevator and the associated parts inside.

I trimmed the stabilizer skins where they interfered with the elevator counterbalances. Real nice fit now.

I then drilled the holes through the elevator control horns where they attach to the stabilizer hinge bearing. I had a .249-.191 drill bushing from my kit at work. Drilled each side one at a time, then reamed the holes to .250″. I’m not going to drill the holes for the elevator control rod until I reach that point in the fuselage build.

Time : 2:10

May 30, 2010 – Had a family moment today. After we got done doing some chores inside and out, I managed to corral some hands to help me hang the rudder and elevators.

Using my temporary pins in place of the bolts, we got the rudder hung with the exception of the middle hinge. Looks like it needs to be adjusted.

I definitely have to trim the outboard ends of the horizontal stab to clear the counterbalance for the elevators. I have at least 3/4″ interference.

Time : :30

May 29, 2010 – First of all, did I mention that I ordered the wings?! I expect them in mid-August.

Things are otherwise about down to the wire on the tail. I installed the rod ends for the hinges on the elevators and the rudder, using the handy-dandy PVC tool I made a while ago.

Since space is tight in the hinge cutouts, you need a way to hold the rod end and screw it into the nutplate that is attached to the spar. This tool has a notch cut into the business end that will hold the rod end so you can torque it.

The rod end is secured by a jam nut.

I also needed to make a way to temporarily attach the elevators and the rudder to their respective stabilizers without using the bolts that will be used for final assembly. Once again, space in the hinge cutouts makes it a little difficult to get fingers in there. You can buy tools that will do this, but I read on somebody else’s site about using 20D nails. Well, I found that while 20D is close to the 3/16′ bolt size, it was a hair too big (about .005″, actually). So I took a nail, “machined” it down to fit, then put a bend in it. The point of the nail will help align everything. That’s what makes this easier than just using the bolts.

The pin slides in nice and easy. Now I just need a helper to hold the surface while I align the ball in the rod end with the hinge bracket in the stabilizer, then stab the pin through all of it.

Time : 1:30

May 19, 2010 – Well, I got the leading edges rolled on both elevators. The central section of each elevator was a particular pain because the skin bulged between the rivet holes. So I decided to add fasteners between the existing ones in that section.

The spacing between rivets in this area is huge for 1/8″ rivets, so adding fasteners was not a problem.

I finally got some uninterrupted time to mix sealant for both leading edges and to install the fasteners. As was the case with the rudder, adding sealant made things much more difficult, because the sealant got all over the place while I was trying to squeeze the two halves together AND install clecos.

Finally got it together, and got the rivets installed. Let it sit overnight, and I wiped away the excess sealant, trying to get a nice edge seal for the seam in the process.

Next I’ll be installing the rod ends for the hinges, and test fit the entire empennage.

I’ve also decided that I’m going to try to go to Oshkosh this year. Never been. I’m trying to find a ride. If this year doesn’t happen, that’s fine. I’ve also got things going on with the house, so things are slowing down a little bit on the airplane.

Time : 4:35

May 5, 2010 – I decided that I needed to replace the hinge for the trim tab, since the aft edge didn’t quite line up, so I ordered the hinge and a 3′ length of hinge pin. Once I got those parts, I redrilled the hinge and installed the halves in the tab and the elevator.

When the hinges were installed and I put the two together, I noticed that the lower edge of the tab was a bit rounded and wasn’t faired to the lower surface of the elevator. This was before my end ribs were installed. The only thing I could figure out was that the bend of the trailing edge wasn’t sharp enough. I gently “percussed” the trailing edge to sharpen it, and therefore flatten the tab a little bit. It fits better. I tried the ribs I had made (see post below). They were a little rounded, so I trimmed the edges of those ribs and test-fitted them. I think things will be better.

The tab will be easy enough to replace later if need be.

I installed the end ribs for the tabs.

I am now in the middle of the most enjoyable task of rolling the leading edges. I read a post somewhere that they thought this was easier than the rudder. Hmmmmph. Pain in the *^$@#$.

As a side task, I made the tool to install the rod ends for the hinges for the rudder and elevators. This tool holds the rod end and lets you torque the rod end into the nut plates.

Time : 4:15

April 22, 2010 – I decided to make riblets for the trim tab and the elevator cutout. After a lot of debate and consultation, I decided to use pieces of fiberglass-faced aluminum core. I used a scrap of floor panel material from the big ones I work on. I said “SCRAP”, as in: I pulled it out of the trash.

I made some cardboard templates, then traced them onto the material, and cut it out. I then trimmed, sanded and filed until I got a good fit in the openings.

When I was happy with the fit, I made new facings out of .020 T-6, spread sealant, and clamped the pieces together. Besides reinforcing the face of the rib, I thought having the aluminum there would make for a cleaner and more weatherproof finish.

After the sealant set up for a day or two, I trimmed the aluminum facings to match the shape of the ribs.

I then test-fitted each rib, and removed honeycomb material to clear fasteners that would be installed in the tab and the elevator that would interfere with the rib.

Since I have ordered a new hinge for the tab, I couldn’t install the ribs in it yet, so I went ahead and installed the rib in the elevator.

The rib is only sealed in, so I used a healthy amount of sealant and clamped the rib in place. When the elevator and tab are all done, I’ll edge-seal all three ribs at the same time.

Here’s the rib in place. I think this’ll work just fine.

I also cleaned, treated and primed the parts for the trim tab, then I riveted the lower edge of the spar and the control horns in place.

Time : 5:05

April 8, 2010 – Well, OK. A procedure that I had my doubts about turned out as I expected. The left elevator has a cutout for the trim tab, and you have to bend tabs to close the cutout. To do this, you make wood blocks to fit inside and out in order to bend those tabs. My problem, and maybe I just missed it, was that I couldn’t find the dimensions for those blocks anywhere. Lots of pictures, but nothing about specific dimensions. So I traced the outboard rib at the end of the elevator, and cut the block to match that. Turns out that was too narrow. But I tried to bend the tabs.

The inside wedge in place, with double-stick tape.

My result. I didn’t go too far; I knew it wasn’t turning out well.

So I’m going the route that I was thinking I’d prefer anyway. I cut the tabs off, and I’m going to insert a riblet to close that area out. I have a rib made, but I’m going to wait until the tab is made so I can get a precise location and gap between the tab and the elevator.

So then I proceeded to assemble the left elevator.

On to the trim tab. Bobby had already bent the tab and bent the ends. (They are done just like the closeout in the elevator).

I located the brackets for the trim actuator and drilled them.

Then I moved to the hinge for the tab. Clamped it in place, and drilled through the elevator skin and the spar. Did this slowly because the hinge could move while I was drilling it. Took the hinge off, attached it to the tab spar, and drilled that side.

I’m still not sure about the bends on the ends. I’ll probably put it all together and see how I like the fit. I may do the same thing as the elevator: cut the tabs off and make ribs. Stay tuned…

Time : 5:35

April 3, 2010 – Some of this is a carryover from previous days’ work, but I did leave some things hanging.

I started assembly of the left elevator structure. I also finished making and installing the tapered shims for the right elevator at the counterbalance skin (see post below this one).

I carefully slid the shims into place.

Using cleco clamps, I held them in place while I drilled the rivet hole that goes through the rib, shim, and the skin…

…then installed the rivet.

The right elevator is now complete except for rolling the leading edge. I’ll do both elevators at the same time.

Time : 1:30

April 2, 2010 – Haven’t gotten around to updating this site lately, so there’s a lot to cover here.

I assembled the structure for the right elevator, then shot on the skin.

When I installed the counterbalance skin on the rudder, I chose to place the skin on the outside of the rudder skin, and faired the trailing edge. On the elevators, I’ve decided to do it per the drawings, with the counterbalance skin inside the elevator skin. I personally think it’s cleaner the other way, but I’m not willing to remove all the rivets to do it over again.

I did, however, neglect to bevel the edges of the counterbalance skin before installation, so now I have a slight gap in the structure. So I’m making tapered shims to fit in that gap.

The shim is very thin; from about .010″ to .025″. Because I only have access to one side, I don’t want to lose it, so I’ll slide it in place, drill it, and install the rivet, all in one operation.

The left elevator will be handled correctly.

Time : 4:40 (Includes elevator trim work below)

March 25, 2010 – Sounds like old age… Anyway, I’ve got the stiffeners installed in both elevators and I bent the trailing edges. Got some help from my bride and my friend Joe. They helped me get access to the rivets in the stiffeners along the trailing edges, since it was hard to get my gun straight on those rivets.

Then it was time to bent the trailing edges. Thanks to Don Crum in Midlothian for the loan of the brake (2 2x8s with several door hinges) The skins come from Van’s partially bent, so you have access to rivet the stiffeners. Once they are installed, you finish the bend to give the nice sharp trailing edge, then the rest of the structure is installed.

I was a little nervous about doing this, but the tool works great, and I got nice crisp edges.

The pictures below show the left elevator’s position in the tool, and the nice bend when it’s done.

Right elevator in the brake:

Next I need to work on the fixture for the electric elevator trim that is installed in the left elevator.

Time : 3:10

March 20, 2010 – It’s been a little slow lately. Nice weather and everything, but I haven’t been able to order the wings yet, so I’ve been pacing myself.

Over the last week or so, I’ve cleaned, alodined and primed the remainder of the elevator parts.

I was concerned last time about the condition of the doubler for the elevator trim. Edge distance on the dimples for the screw holes was a little close for my comfort. After looking at it and looking at a couple of other airplanes, I think it’s going to be OK. A friend pointed out that the nutplates can act as doublers for the material also, adding a little bit of extra strength. The only thing on this plate that I did differently was to countersink the holes for the nutplate rivets. One reason is for maintainability later. If a nutplate goes bad, I’d rather not have to dimple a new one before installation. Well, it’s installed in the left elevator skin now.

I’ve installed the stiffeners in the left elevator. Lots of fun getting the ones at the fwd end of the stiffeners, right up in the fold of the leading edge. Note the prodigious use of the green-striped rivet tape in the third picture. That tape hold the rivets in place so you can rivet from the back.

Time : 4:10

March 9, 2010 – Finished cutting the right elevator counterweight. Pretty good workout.

Double-checked the drilling for the left elevator structure, then I dimpled and countersunk everything that needed it. Cleaned, scuffed, and alodined the skins and the stiffeners for both elevators, then primed them. The tedium is overwhelming. I thought the pile of stiffeners would never go away. But they’re done, painted, and ready to shoot. I still have to clean, treat and prime the rest of the structure, but if it rains tomorrow I can rivet the stiffeners to the skins and still be ahead.

I’ve dimpled the panel and the doubler for the elevator trim, but I’m not really happy with them. I’m on my second access panel, and it dimpled OK, but I don’t like the edge distance on the nutplate holes for the doubler.

Time : 6:00

March 4, 2010 – Continued dimpling; got the left elevator skin and the doubler plate for the elevator trim cutout done. Used a soldering iron to remove the protective plastic from the skins. Searched all over for mine, and couldn’t find it, so I bought a new one. Now I’m sure I’ll trip over my old one. That’s how it works.

Then I sorted and labeled the stiffeners for both elevators in preparation for alodine and paint.

Started assembling the structure for the right elevator. Now I’m doing the trim of the right counterweight. Cutting the lead isn’t as easy as I thought it might be. I’m a little scared of using an air tool to cut it, because of the dust, so I’m starting out doing it by hand.

Time : 3:15