Next up: test the fuel tank, install the root skin, close up the nose skin.

The root skin starts by taking the wing root angle and bending it around the root rib. The angle is completely straight so this is achieved by flattening one end of it with a plastic hammer.

And then to curve the metal, you put crimps in the flange. I got to use another new tool to do the crimping.

It was at this point I realised that I need the i/b nose skin bent back over and I don’t want to do that until the fuel tank is ready to be sealed in. So I set the angle aside and looked over the wing tip.

At Christmas time my Dad and I had looked at putting the wing tip in place and it looked to be a bit tough to get it in place. It did take some moving around, pushing and shoving but I finally got the tip in what looked to be the right place and I first drilled pilot holes through the pre-drilled holes in the skins, and then opened up for an A4 rivet.

Not sure why all this took 90 minutes but that’s what the log says.

The fuel sender arm has to bent at a certain place and angle. This required massive feats of strength (I’m a weakling!) and was probably the worst task of the day. Anyway I got it bent to what I think is close enough.

The video and photo guide make it look easy to get the sender inside the hole, it was not. And for the longest time I was sure I had made the hole too big for the sender to line up with the top of the tank. But just as I was about to take the whole project down the dump it was in and each screw was locked in place. Since I had only been experimenting I had to take out each screw one at a time so as to apply a fuel safe sealant around the screws to prevent leaks.

The fuel sealant is NASTY.

The tank and the sender unit need to be grounded to the wing so I cut some wire and attached some terminals. These will be grounded on a rivet in the spar.

The tank is now ready for final install inside the wing but first we shall test it for leaks.


Finally, this was the first time trying out my new wire stripping tool – it is awesome! No more using my teeth to strip the wire or accidentally cutting the wire using a regular crimper/stripper.

The fuel tank is held in place inside the wing by sticking cork strips to the edges so that it is wedged in firmly, with no metal part touching metal.

I kept adding cork until the tank fit snugly into the bay.

The open end of the tank is held by a fuel channel which needed to be positioned tight against the cork strips and then, using a very long drill bit, holes were drilled through the channel into the bottom skin.

The edges of the channel are attached to the rear ribs via l-angles riveted to each end.

First bracket pilot drilled in place

Enlarging the holes in the other bracket to their final A4 rivet size

The final task for fuel tank placement is to drill holes through the top skin into the fuel channel. So I had to put the top skin back on

and to determine the placement of the holes I drew an extended line down the middle of the fuel channel and then used a ruler to join them up on the top skin. I marked some rivet locations on the skin and started drilling.

I’ve done all I can do on the fuel tank now until I can get a tool for cutting a hole for the fuel sender. This requires a 59mm hole to be drilled and I’ve been putting this off because (a) it’s scary, and (b) the tools for doing this don’t fit my drill.

As two final acts for the day, there were two l-angles to rivet to the ends of the spar tip and rear channel. These were simple l-angles cut to size, rivets holes marked, drilled, back drilled to the wing and then riveted.

The spar tip

and the rear channel

I suppose these will act against the wing tip when it is inserted.

First though, I drilled some holes in the rear channel for the pitot tubing and ran it from the tubes out through the trailing edge

This allowed me to close up the top skin on the outboard side. I had to finish deburring the holes in the skin but it was soon back on the ribs clecoed in place, and including the l-angle stiffeners.

Then it was ready to rivet… here I go….


Halfway there, more rivets ready to pop.

Need to polish aside, I think the wing looks great!

The top row of rivets is left until the nose skin is ready to rivet. Next is the fuel tank, root skin and wing tip.

Before riveting the skins on we have to put a few things inside. First up was the tie down ring that was drilled quite some time ago. A bunch of A4 rivets took care of that.

Next was the pitot tube and this caused me quite a bit of consternation because the plans differed a lot from the video and my online research didn’t really reveal any official location to put it in. A few forum posts later I went with a suggestion from one of the other builders that seemed to combine the best of all answers. I marked the location on the inside of the skin.

I pilot drilled some holes in the pitot tube.

Then I drilled through the pilot holes into the nose skin, clecoed it in place and opened the holes to size 30. A little deburring and priming, then I could rivet it in place.

and from the top

I have to run the plastic tubing into the trailing edge and out the wing.

One difficulty is that I had to try and line the pitot tube straight from under the wing in the semi-dark, I hope it is at least close!

This marks the end of my Dad’s visit and his help in the garage. It has made a big difference to have someone helping and cajoling me on, I’ll definitely miss him.

From here, the major task is to install the fuel tank plus a few extra bits and then rivet the skins in place.

The trailing edge has no pre-drilled holes so you must slide it under the top skin and back drill through it and into the rear channel (that also has no holes). It is a critical measurement to set the trailing edge distance from the flaperon arms to 70mm. I remembered reading a forum post a long time ago questioning exactly how to take the measurement, I found it and we did it correctly.

We taped the trailing edge to the top skin and being very careful not to disturb the measurement we drilled pilot holes down the rear channel line, and then went back and open them to size 30.

The video has you drill out the flaperon arms before the ribs are riveted to the spar but I decided to follow the photo guides and leave it until now. This was a mistake. Anyway, first off we to cleco the flaperon arms into place on the ribs.

and with the arms in place on the ribs we opened the holes through the rib for an A5 rivet. The problem is that the skin makes it impossible to get the drill in the bottom row of holes.

My Dad came up with the idea of getting a very flat hand drill that would allow us to open the holes by hand, we found one on Amazon and ordered it. At the same time I asked on the Zenith website and one suggestion was to use some 12″ long drill bit so I ordered some of them too.

In the meantime we had to make the l-angle supports for the flaperon arm, cut some l-angle into the right width and marked a line on the arm where it sits and then drilled through both items to get our holes.

Putting the flaperon arm back inside the skin allowed us to drill the holes required in the bottom of the l-angle from underneath the wing.

With nothing more we can do until the drill/drill bit comes we located the top skins and clecoed them onto the ribs. We also put the l-angle stiffeners under the skin (this was tough with the skin in place!). With all the holes lined up, we drilled them out to A4 size.