Category: Aft Fuselage

The build instructions miss out lots of information. I suppose Van’s couldn’t write every little detail or the instructions would be huge. An example of that is when to rivet the top skins on. Looking through the plans it does tell you when NOT to do it but not when it should be rivetted on.

So after lots of deliberation I decided that I could mount the first of the two aft skins without too much consequence. So first I cleco clamped the skin in place.

Then I climbed inside the fuselage to buck the rivets while my dad was on the rivet gun. The smile on my face was soon lost once I tried to get OUT of this space! My goodness that was a challenge!

While inside I decided now would be a good time to permanently fit the seatbelt anchor brackets. So they were bolted in place and torqued to the correct specs.

Next I started the ADAHRS bracket. This is a new part that vans have recently offered. As it’s made by Van’s for this aircraft I figured why not. So I deburred it, clamped it in place and match drilled all the necessary holes as per the OP drawing and instructions.

With a bit more time spare this week I decided to fit the floor pans in place. I’m pretty sure these are all match drilled already from when the fuselage was upside down but I wanted to triple check. Pilot side first.

Then the passenger side. I checked all the holes and sure enough they were all done. I also fitted the baggage side panels and checked those too.

That’s all for this week. It definitely feels good to be back on it.

Wow! It’s been almost 5 months since I last worked on the project. I really need to have a word with myself or this project will never get finished!

To get back into the swing of things I decided to tackle the static system. The static system is a series of tubes that connects to the instruments so they know the outside air pressure and therefore the altitude.

I already decided I was going with the Vans large rivet solution so I practiced setting it 3/4 of the way on some scrap and knocking out the central mandral. It wasn’t that hard but it sure was scarier on the actual plane than on the scrap piece.

But after setting it 3/4 of the way and then giving it a gentle ‘thwack’ with the hammer and a support block behind the skin the mandrel was soon out and a rivet set in place on each side of the plane.

Next I ran some tubing between both rivets and sealed them in place with RTV sealant and a cable tie. Along the top I was worried about chaffing so I reinforced the tubing there with a larger piece of tubing.

The important thing routing the tubing is that none of the it is lower than the rivet otherwise water may collect and block the air pressure.

A close up of the tubing routing and the t-piece that allows the tube to go to the front of the aircraft and ultimately connect to the instruments in the future.

That’s all for this week. I’m definitely going to try and be more regular with the visits to the workshop or I’ll be too old to fly by the time it’s done!

Today I started by fitting the rudder cables into the fuselage. I was apprehensive that they would not squeeze through the rudder cable fairings I made but thankfully they fit, just.

I fitted the protective tubing and the adele clamp to hold it in place.

I ran the rudder cables all the way through to the front of the aircraft. Remembering not to forget the snap bushings in all the holes along the way too. Yeah ok, I did forget some and had to back pull the cable and fit the bushings and then redo the cable.

After that I riveting the F-709 bulkhead to aft deck.

And then mounted the j-stringers in place.

That’s all for this week.

Now that the parts have dried it was time to assemble them for the last time. I started with the elevator bellcrank. Once rivetted together I assembled the parts to make sure I had everything.

Next I riveted the F-656 Gussets that add strength to the bulkheads.

Then on to riveting the forward gussets that sit up front against the firewall.

Then I riveted the rudder cable exit fairings.

Finally I riveted the aft deck and checked levels to make sure nothing drastic had changed since it was last levelled.

It’s soon going to be time to install the static ports. Vans have supplied a pair of very large blind rivets which you are supposed to set 3/4 of the way and then knock the middle out. I’ve also got some that came as part of the Dynon Pitot Static upgrade kit. Before deciding which ports to use I thought I’d weigh them both. As you can see the Dynon upgraded one on the left is almost 10 times heavier that the ones Vans supplies.

In addition I have read on the forums that the profile of the Dynon static tube can cause inaccuracies in the altitude readings it gives.

So I’ve decided to stick with the good ol’ Vans supplied rivets. I’ve ordered a few spares so I can have a go at knocking the middle out. Not today though as that’s all for this week.

This week consisted of just 1, long, work session. Priming. Lots. Of. Parts.

Not a lot else that can be done until this all dries (or is it cures?).

More match drilling again, this time skins to the ribs.

Another session today drilling the J Stiffeners to the skins and ribs. The process was pretty much the same as the other stiffeners. Draw a centre line, fit the stiffeners and then back drill through the skins and ribs.

The first job of this session was to finish off the tailwheel skin trimming. On checking I wasn’t 100% happy with the clearance of the skin to the tail spring mount so I filed a bit more. I also opened up the forward hole to allow access to the nut that holds the spring in the mount.

Once I was happy with the tailwheel skin and mount it was time to start on the ‘fun part’ (actual words from the instructions!). First I laid out two saw horses.

Next I located the aft fuselage bottom skin and clecod on the F-708 & F-709 bulkheads and bottom J-Stiffeners.

Next I loosely placed the upper J-Stiffeners and clecod on the right side skin.

Then the left side skin.

Now I clecod the F-706, F-710, F-711 & F-712 bulkheads in place.

I tell you what the instructions weren’t wrong, that really was fun and it looks so awesome!

Motivated by my earlier session I spent the rest of the afternoon building the Aft fuselage. Instructions insist on removing any twist from the fuselage before drilling the stiffeners. I tried to do this with the fuselage the right way up but I soon realised it was much easier to make sure it was square by turning it over. I then put a plumb bob line at each end of the fuselage and used the tooling holes on the aft bulkheads to ensure that the string was centered over both holes. On the front bulkhead it was not so easy so I centered a ruler over the pushrod hole and aligned the plumb string with the tooling holes.

And the rear bulkhead…

Once I was sure that the fuselage was square I aligned the centre line I drew previously on the stiffeners with the pre-punched holes and then drilled the upper stiffeners to the structure on both left and right sides.

That’s all for today.

This is it! Making this cut will make this aircraft a tailwheel, a decision I agonised over for many hours. The plans gives a template for the cut but, like many other builders, I didn’t want to cut the original plans so I made a photocopy of the template from the plans and used that to mark the skin instead.

Once I marked the template I then used a 1/4″ drill bit to drill the end of the curve and broke out the dremel to rough cut the lines.

Next I used the dremel with the drum sander bit to tidy up the cut followed by hand filing for even more accuracy. The cut out is so that the tail spring mount can fit between the F-711 and F-712 bulkheads but when looked at the part it didn’t look quite square. I decided to check how far out of square it was…

Thankfully it looked worse than it was, it was actually only 1/32″ out of square. I can live with that. On first attempt I noticed the mount didn’t fit so I had to trim the cut I made earlier. Unfortunately it still didn’t fit but after referring to the instructions again I realised that F-712 also needs trimming to allow room for the welding fillets.

It took several iterations to remove just enough of F-712 bulkhead. I really didn’t want to take too much off so it was a case of trim a bit, check and repeat. Next I needed to drill the tail mount to the forward F-711 bulkhead through the vertical bars as well. The trouble is that is a deep hole and it was difficult to see in there. The instructions simply say to drill it square to the bulkhead, talk about understatement! Eventually I read Mike Bullocks blog which gave a fantastic tip of marking a line 12/32 from the top and from the edges.  It worked a treat though it was an absolute bear lining it up and clamping it all. In the end I got it done and the bolt holes are drilled #30. I’ll final size them later on.

This session was a lot of work for not much reward. I’m pleased it’s done though.

That’s all for today.