Category: Leading Edges

Landing light lens work

April 19, 2011 – I began working on installation of the landing lights in the wing leading edges.

I am using the Duckworks rectangular lights. The instructions start by having you mark and cut the lenses to size. They suggest an ideal measurement of 3/4″ on the top and bottom and 5/8″ on the sides. I went ahead and marked those dimensions on the leading edge around the cutout, then placed the lens over the top of the leading edge and traced those marks.

I cut the lines using my dremel.

Here’s the lenses after cutting:

I used a large, coarse file to clean the edges, then I used a utility knife to scrape and slightly round the edges. I’m really happy with how they came out. I still need to cut the corners, but I may wait on that until the attach brackets are installed, then I’ll cut the lenses to shape.

The next step is to drill the lenses through the leading edge of the wing. To help hold the lenses tightly in place, you use tape so you can pull the lens tightly into position.

I also painted the brackets for the lights. These will be installed inside the leading edge.

Time: 2:10

Installed stall warning vane in left leading edge

April 4, 2011 – I installed the stall warning vane and switch in the left leading edge. I enlarged the tooling hole in the wing spar to 3/8″ and installed the snap bushing.

I attached the switch to the bracket previously installed  in the leading edge.I’d forgotten how clean things can be without sealant. 🙂

I terminated the signal wire and installed it on the switch. I’ll pull the wire through after the leading edge and the top wing skin are installed.

Time: :15

Began install of right leading edge

March 29, 2011 – I started installing the right leading edge to the main spar. The plans call for solid rivets for the rib/spar install, but access to shoot them is something of a challenge, so many people use pop rivets. I really didn’t want to do that, so I decided to use hi-locks, a fastener that theoretically only requires access to one side. Hi-locks are fasteners made of either steel or titanium that are secured with a collar that has wrenching flats that break off at the correct torque. I wanted to install them from the forward side of the spar so that I could install the collars on the aft side where I had room to work. They would also be easier to remove should the highly unlikely need arise. As it turns out, there wasn’t enough room to get a wrench or socket on the collars from the aft side, because they were up against the main ribs. So I drove the fasteners in from the aft side and installed the collars on the forward side. I used -5 fasteners, so I had to enlarge the holes in the spar and the ribs to #21. That drill size also allows for an interference fit of the hi-lock.

Did I gain anything from using these over pop rivets or solids? Probably not. I ended up having to modify my pop riveter for the tank z-angles anyway.

I still have to install the rivets for the leading edge skin and the main spar.

Time: 3:45

Repaired potential rib crack

March 13, 2011 – Last week I started riveting the joint strap into place on the left wing leading edge. My tungsten bar slipped off the rivet and I thought the rib might be cracked.

So I drilled out the installed rivets and removed the rib and the strap again. The rib wasn’t cracked, but the potential was definitely there for one to develop later on.

I blended as much as I could, then I drilled through the deepest part of the gouge. I made a strap to go on the inside of the rib flange. probably over-engineered, but I’m confident it’ll be good forever.

Time: 1:05

Leading Edges assembled

December 26, 2010 – I hope you had a Merry Christmas. After the festivities, I had some help riveting the rest of the right leading edge. Earl Routh was visiting for Christmas, and he and I went out at about 8:00 to do the rivets in the very front of the assembly. We ended up finishing.

He then clecoed the leading edge to the wing spar, and we clecoed the inboard rib and splice strap in place in preparation for the fuel tank assembly.

Before I start the fuel tanks, I want to remake the doubler for the stall warning access panel. I removed the doubler yesterday, and I’m going to make a new one out of .040″ instead of the provided .025″ material. I don’t like the idea of dimpling the nutplates, and this material is really too thin to countersink for those attach rivets, so with the thicker material I can countersink to my heart’s content.

Time: 4:25

Leading edge assembly

December 21, 2010 – After not being sure if I could rivet the leading edges by myself, I decided yesterday to give it a try. I took the assembly out of the cradle and put it on the table. Things went a lot easier.

Before I started assembly, I installed the nutplates for the landing light brackets.

The fasteners at the leading edge were a little more difficult to reach, but I took my time, and things came out OK. I also installed the access panel doubler for the stall warning vane.

The left leading edge is clecoed onto the wing spar.

I’ve started on the right leading edge. I’m doing this one a little differently. Hopefully this will give me a little more access, since the top rivets are a little more difficult at the leading edge.

Time: 3:10

Miscellaneous leading edge items

December 18, 2010 – I am at the point of assembling the leading edge skins to the ribs, and I quickly realized that I’d rather not do this alone. So I’ve done a couple of other odds and ends.

I assembled the stall warning switch that goes in the left leading edge.

I have the rib installed in the skin of the leading edge, and I’ll install the switch later. That way the vane won’t get damaged.

I also took the time to countersink the rest of the holes in the main spar that will accommodate the dimples for the leading edges. So all the holes in the spar are now countersunk, and I can paint that face of the spar cap on each side before anything gets permanently installed.

Time: 1:55

Painted leading edge ribs and skins

December 14, 2010 – The most important thing about today is that it’s my 25th wedding anniversary! But due to the fact that LJ had to work, I still get to work on the airplane.

Over the last week I have alodined and primed the leading edge ribs, and got them and the leading edge skins primed. I also painted the landing light bays the traditional flat black. I  read a note in the instructions for the Duckworks lights where they advise painting the upper surface of the interior of the landing light bay a brighter color, since the cutout points more down than forward. A lighter color on the top will permit some reflection of the light downward. So I painted the upper portion white as you can see in the photo. I also painted the sides of the ribs that will form the bay for the lights. I used the nutplates as the guide for where the line should stop, since that is where the bracket will sit.

Time: 3:10

Deburred, dimpled, and cleaned leading edge parts

December 9, 2010 – I have been busy, as the post title says, deburring, dimpling and cleaning the skins and ribs for the leading edges. Not really much to talk about; this is just a lot of tedious work. I did get the inside surfaces of the skins painted yesterday. Right now I have scotch-brited the ribs. They still need to be cleaned, then alodined and painted. After that I can start assembly.

Time: 5:45

Began prep work for stall warning

December 1, 2010 – Another component in the left leading edge I wanted to get to is the stall warning vane. This is a little vane that sticks out of the leading edge of the left wing that floats and makes a switch in the event of  a stall. It seems like not a lot of people have these installed, but I see no reason not to go ahead and install a simple piece of insurance. The left leading edge skin came drilled and cut out for it anyway, so I figured I may as well do it.

Since the skin had cutouts already, doing some of this work was pretty simple.

There’s an access panel on which I needed to drill the holes to #40. It will need to be dimpled and have nutplates installed.

I then had to cut out the slot that the vane will stick through. There were two small holes in the leading edge that I just had to enlarge, then cut out the material in between.

The rib that the switch attaches to goes right inside the leading edge. I put it in place and drilled the rivet holes to #40. I’ll dimple this rib and paint it when I do the rest of the leading edge ribs, and then I’ll install the guts of this thing later on.

This first picture is just the little rib that holds the switch, and the second picture shows the access panel with the rib towards the front.

Time: :40

Began landing light prep work

December 1, 2010 – Over the last couple of days I have done the sheet metal work in preparation for the landing light installation. I decided to get the Duckworks regular 55W rectangular lights. I’m putting a light in each wing, and they will be in the most outboard bay, just inboard of the wingtips. The kit comes with very nice instructions.

To start with, I cut out the template for the leading edge cutout. The edge of the template also gets cut, so it can align with the fasteners in the rib inboard of the light. I aligned the template in place on the leading edge and taped it in place, then traced the outline of my cutout.

To do the cutout, I began by using a Unibit for each corner, then I used a cutoff wheel between those holes. Then a combination of rotary files and scotchbrite discs until the opening was nice and smooth.

I then used a template to locate the holes in the ribs that the landing light bracket will attach to. The holes will contain nutplates, and the attach screws can be loosened, allowing the bracket to be adjusted. I drilled the holes through the template, took them up to #10, then used a nutplate jig to drill the rivet holes for the nutplates.

I’ll install the nutplates after everything is painted.

Time: 2:40

Leading edge inboard ribs and joint plates

November 25, 2010 – HAPPY THANKSGIVING!

Yesterday I drilled the leading edge ribs to the main spar. The easiest way I found to do this right now was to open one side of the leading edge skin. This would give me access so I could place clecos on the inside.

I celebrated this morning by drilling the joint plates and inboard ribs for the leading edges. The joint plates are strips of aluminum which will connect the fixed leading edge to the fuel tank on each wing. Lots of fun because you have to fit pieces together where there’s not a lot of space.

I did the first one yesterday and figured out how to do it. This morning I did the other one and took pictures of the steps. I know that people do this different ways, but this is what worked for me and it wasn’t all that difficult.

I started out by measuring 3/10″ from the rivet holes in the spar. I arrived at this figure because the rib flanges are .6″ wide. .3″ would be half of that width, and would represent a safe edge distance for the rivets.

I put the end rib in place, lining the inboard (visible) end with the marks I made, then I drilled  the rib flange from underneath.

You then mark 1/2″ on the joint plate. This will be the fastener line through the rib, and will allow the plate to stick out 11/16″ past the skin. This will be where the outboard edge of the fuel tank attaches. I also made a line on the rib flanges at about the halfway point. This would provide an indication of safe edge distance.

The plate then needs to be somewhat pre-bent to fit around the nose of the rib. I did this by using a couple of cleco clamps to hold the plate to one of the ribs, and just bent it around. Precision does not matter at this point.

the plate is then slid into place between the rib and the leading edge skin. This is very tight, and you have to tap the plate into place. I experimented with different ways of doing this, but the simplest way was to insert the plate at the top, then slide the sides in. When the plate is in all the way around, look through the holes in the skin to find the line at 1/2″ on the plate. When it is in place, you should have 11/16″ sticking out from the skin for the tank attach.

Because it’s hard at this point to know exactly where the rib is aligned, I used a scrap piece of titanium (stainless works too) to just drill through the skin fastener hole into the plate.

Once that hole is drilled, you can look for the line drawn on the flange of the rib, center it in the hole, and drill it.

Cleco that hole, check the location on the interior, and drill the rest.

Time: 3:55

I actually drilled the bottom hole on each side, then picked up a hole about halfway up each side, then a top hole on each side. Once those are done, nothing will move, and you can safely drill the rest of the fastener holes without using the titanium or stainless.

Leading edges

November 23, 2010 – I have both wing leading edges clecoed in place.

When I started on the left leading edge a few days ago, I pretty much just clecoed the ribs into the skin and placed the leading edge on the spar. It did not fit at all. I couldn’t get the leading edge pulled down far enough to line up the rivet holes on the spar. I knew that people had had problems getting the ribs to fit, so I took the leading edge assembly back down and took a closer look at things.

What I found was that the small flanges at the nose of the ribs were not round and didn’t lie flat against the skin. So as I placed each rib into the skin, I slightly bent each tab, then I polished down the forward surface of each rib to make it round, with no points that stand out that could gouge the inner surface of the skin.

I also found that although the ribs and skin are pre-punched, there is a hole that is in the skin, but not in the ribs. This is the second hole from the leading edge, on both the top and bottom of the leading edge. I marked through the hole in the skin, looked at the rib, and found plenty of edge distance for the new hole, so I drilled them all in the ribs.

To assemble each leading edge, I peeled the blue protective film from the inside of each skin, tweaked each rib, and clecoed the ribs in place.

I then drilled the rivet holes in the leading edges as they were set in place on the wing spar.

Time: 3:15

Started left wing leading edge

November 19, 2010 – Today I also started the left wing leading edge. When I took out the skin, which is rolled so it can wrap around the ribs, I noticed a cutout for access, but I had no idea what it was for. A quick Google search revealed nothing, then it hit me: with the wing kit I had also received a kit for the stall warner. I previously decided that I did want to install that, so I broke open the subkit and found drawings and instructions for installation. That’s what the access is for.

Got out the leading edge cradle I got from Kenny Haberstroh, and placed the left leading edge skin in there. I started clecoing ribs in place. That’s a little bit of work; getting the skin to pull down and align with the rivet holes in the ribs. The instructions say to start with the upper forward holes, work back across the top, then go from the front to the back on the bottom.

Time: :30