Van's  RV-8  Project

Wings

The wing kit was received early in November 2012. After inventory and setting up, actual work started on 17 November, 2012.

I will install Duckworks HID taxi/landing lights (done), a Falcon heated Pitot tube (done) & Deluxe locking caps (done) from Van's.

In a later stage, strobes, LED navigation lights, manual instead of electric aileron trim and an Auto Pilot servo motor will be installed. These four items are not purchased yet and will be installed at a later date.






Prior to receiving the wing kit, I re-organized the shop to maximize the space and built a wing stand. It will support the wing structure during construction. It's on wheels to move it around. In this picture it is not complete as I still had to install alu angles to hold the main wing spar.
Both left and right wing spars. Inspection found them to be spotless. The gold colour is the anodizing of the aluminium. Truely nice pieces of workmanship, too bad they won't be seen after the wing is built.
The first job to do is countersinking holes for platenut rivets. It's a little intimidating to do at first because you don't want to damage the spar. All holes were countersunk and checked for size with a rivet.

The holes are then spot primed.















Here are 30 platenuts, there are 120 to do on both spars.
















After, 120 bigger holes for screws are countersunk and primed also.
From a plan drawing, spacers for the wing tie-down brackets are fabricated from a stock aluminium bar.














One hole on the stock tie-down bracket is drilled and then the bracket is squared bolted and clamped to the spar for final drilling of the all holes.














Here, the spacers and the tie-down bracket all drilled, deburred and scored, ready for priming.













The platenuts are installed and the assembly is bolted on the spar for testing.













Behind the spar, aileron brackets are bolted with the tie-down bracket.
A plastic grommet is installed in the hole on the left spar. This hole will have the wires for the stall warning system.













The tie-down brackets need to have their bottom holes tapped to accept the tie-down bolts.
Work on the rear wing spars starts with match drilling  doubler plates through the spar itself.

This one is on the outboard end.

















This doubler plate is in the middle, it's partially finished as a hole still needs to be cut for the aileron pushrod.

















At the root end, bigger doubler plates are match drilled.


















After drilling, deburring and priming, the doubler plates are riveted to the rear spar.

Note that not all holes get a rivet at this stage as ribs and other parts will be installed later.

A good study of the plans is needed here to leave the correct holes empty.










Seen here are the middle doubler plates with their aileron pushrod holes.

Again, lots of empty holes.















At the outboard end, the plates with their empty holes.
The wing ribs as received from Van's.

As with all other parts, these need edge and lightening hole deburring.
Followed by squaring and fluting the flanges to straighten the ribs out.












The ribs after treatment.

All stack up nice and square now.

The 14 main wing ribs are clecoed for the match drilling to the main and rear spars. Starts to look like a wing!!!
The next step is to prepare the Z brackets that hold the tank to the main spar.

I wish I'd seen this post before in VAF.
And this builder's site.

It puts to light a known problem with the drilling of these Z brackets and the instructions should be changed.

My initial hole is slightly off center to the left. Even if it had been perfectly centered, the hole for the baffle (centered and square with the spar) would still be off to the right... So new parts are ordered and I will change the manufacture process to get it perfect next time. Will detail the new procedure when I get the new ones.
While waiting for the new parts, all 28 main wing ribs get 2 holes (the 2 bigger ones) to further receive a conduit that will hold all wiring in the wing.

The 2 most outbound ribs only get one hole for now (the one on the left) as one pilot hole needs to be intact for future aileron alignment.











The ribs are then scored with ScotchBrite pads for priming.

On the left, a scored rib, on the right, before the scoring.











All main wing ribs are now ready for priming.
It's time to rivet the ribs to the spars. I used an offset ("s" shaped) rivet set since I didn't want to rub the gun against the rib.

Almost all the manufactured heads get blasted (no. 2, 4 and 5 here) despite trying with low to high air pressures and my applying sufficient hand pressure to the gun to keep it from moving on the head.

I installed only 6 OK rivets out of 10 on 2 ribs and had to remove 19, some more than once, including these 3. I later tried the straight set, and while pushing slightly on the rib is needed, it was a bit better but not quite. Frustrated, I did a sample rivet on pieces of scrap on the bench and it was perfect.

I have to suspect that maybe the spar vibrates and causes this.

After removing the spar from the stand and worked on the work bench, the rivets turned out ok.

Lesson learned, for these rivets, do not rivet on the wing stand but on a stable support!!

Riveting the ribs to the spar.

Because of the flange sides, I suggest to start with the third rib from the root, then the second, then the first, then the fourth for ease of installation because they are close one to another.

Then the rest can be done without any particular order since they're further spaced.

Pretty straightforward, apart from the fact that the outboard ribs need a shorter rivet.

Remember to do this on the worktable and not on the stand and don't rivet to the spar the last, outboard rib!!

Riveting the rear spar needs some care as there are 4 different rivet lenght used within 2 types, (normal & flush).

And on almost all ribs, there is one hole left open, (seen here as a horizontal line between the clecos), for further installation of an additional part.

On one half it's the lower part that's left open and the higher part on the other half.

So pay close attention to the plans!! The most outbound rib gets flush rivets!!

The wing rib/spar assembly is back on the wing stand.

The following step is to prepare the skins.

Next to the fuselage, an extra layer of aluminium is installed under the skin to permit entry and exit by walking on the wing. The doubler is made from aluminium sheet. It's  slipped under the skin, the side edges are aligned and the forward part is aft of the skin by 9/16" (green line).







The doubler is positioned and clamped under the skin for drilling. The skin is used as a template.

The extra lenght at right will be cut to 26" later.

This cut could be done prior the drilling.










The first holes are clecoed to stabilize the assembly.

Then all holes are drilled using the skin as template.









The 2 top skins and the doubler are clecoed to the wing for match drilling.















The bottom skins on the wing, ready for match drilling.


















After drilling the main skins, the leading edge was assembled and clecoed on the spar for fitting and drilling also.




After the leading edge assembly is clecoed to the spar, the most inboard rib needs to be installed and drilled as it does not have pilot holes.

First it is drilled and clecoed to the spar only. The rib web needs to be flush with the skin edge. A 12" long drill bit was used because of the restricted space below.

Since the rib has no holes, it is installed and clamped. Then marks are made on the rib flanges with a felt pen through the skin holes.

These marks will show where the holes will be to permit fluting the rib.























This strip will have a lengthwise line drawn 1/2" from its edge.

It is then inserted between the skin and rib, the mark in-line with the holes in the skin.

It will then protrude 11/16" on the tank side for the tank skin to be screwed through the strip.










A rubber mallet is used to gently tap the strip and the rib in place. A ruler is used to measure the distance between the rib and strip (11/16"). When all is in place, the strip and rib are final drilled using the skin as template.

















The leading edge assembly is removed for drawing  on the bottom skins intersecting lines over the tie-down bracket.

The leading edge assembly is reinstalled and the lines on the bottom skin are then extended until they cross.

There is where a hole is drilled to permit the tie-down bolt to screw in the bracket.

There's a hole already made by Van's but it's not correctly centered. It is expected as such, hence the need for the intersecting lines.





Inside the rib, on the left can be seen the gap between the skin and the tie-down bracket. If forced, the bolt could press the skin against the bracket causing skin deformation.

An inside nut will be installed in the bracket to prevent screwing the bolt too far.


Starting my 2nd set of tank brackets proceeding differently from the Van's instructions.

First, instead of a centreline on both flanges of the brackets I marked only ONE flange per bracket.

IMPORTANT: the root bracket gets its hole shifted 1/16" towards the edge, (further out) while the 6 other get shifted 1/16" towards the flange, (further in).

DO NOT drill the 1/8" hole on the other flange like the instructions say, the other flange is left UN-DRILLED for now.
A precision punch is first made in the middle lengthwise. Note the line is off-centered towards the edge this being the root bracket.

This off-centering towards the edge will allow a wrench to be easier placed when bolted to the spar.

For the other 6 brackets, the shifting of 1/16" towards the web (inside) will give a little more room for the blind rivet tool when installing on the tank.

I then drilled in 3 steps, using a 3/32", a 1/8" and finally the 3/16" drill bit, measuring after each drilling to ensure the hole keeps centered.
The bracket is then positioned to the spar with a loose bolt through the middle hole.

It is then squared with the spar's flange lip, then bolted tightly and clamped down firmly.

The 2 remaining holes are then drilled through the spar, making sure that all is always nice & square.

Notice that the other flange of the bracket is still UN-DRILLED.
Following the drilling of the Z brackets, then the installation of the platenuts on them, the tank ribs are clecoed to the skin.

I started with the 3 leading edge holes on the top then by pushing down on the rear flange while the skin is on a soft surface, it's easier to install first the bottom rear cleco then the others alterning top and bottom.
The new Z brackets are primed, got their platenuts and are bolted to the spar.

Still NO HOLES on the forward flange.













The assembled tank skin with ribs and rear baffle is installed on the spar.

It needs to be pushed against the leading edge assembly so the skins touch and alignment is perfect. Also pull the tank skin towards the spar by clecoing it to the spar.

Some use ratchet straps to help pull down the tank.
Only the root Z bracket is exposed at this stage.

Now that the tank is correctly set, the bracket is drilled perfectly using the rib and baffle as template.

Don't forget to put a scrap piece of aluminium underneath the bracket to protect the spar from the drill bit.

Because of the closeness of the rib, the angle drill is used.
Next, the leading edge assembly is removed to expose and drill the outboard Z.

Once both end Z's are drilled and clecoed, the baffle can't move.

Remove the tank skin and ribs by unclecoing it from the baffle and spar but leave both end ribs clecoed to the Z's.
The remaining Z brackets can now be drilled through the baffle.

A drill stop is used to prevent damage to the spar when drilling through the baffle.











By using this method, the baffle and Z brackets are straight and square and match drilled correctly.
The tank skin, ribs, baffle and stiffeners are drilled through.

The baffle is not yet installed here to permit the installation of the stiffeners seen here on the bottom skin.











Along the baffle, all the top and bottom skin holes are countersunk instead of dimpling.

This way, the baffle will be easier to slip in its place when the tank is riveted.
Next, two tank attach angles are made by first cutting some stock aluminium angle.














A centre line is marked and a 1" radius is drawn with tangents down to the lower corners. I used a 2" ScotchBrite wheel as template. A smaller radius is drawn in the corners.

The rough cut was made with a Dremel tool using a steel cutting blade. It was noisy, slow, dusty and smokey. The cutting wheel was also almost worn down completely for these two cuts.







Not having a band saw, this other rough cut was done with a regular hacksaw. This cut is to conform to the rib end. It is drawn wide and will be adjusted with the grinder. Compared to the Dremel tool, the hacksaw was quicker, less noisy, less dusty, and no smoke. A clear winner.











The tank attach angle after fitting and polishing.

Just a view to show the before and after of the tank attach angle.












Drilling holes in the angle, I used the plan to measure the distances of the holes from the angle's straight side.













The reinforcement plate will be on the other side of the rib.It will be clamped in position for match drilling.

The tank root rib is modified by cutting a large hole the size of the round bead.

A fly cutter in the drill press was used for this.
















The access plate is clamped, the straight edge is parallel to the bead and it's centered top and bottom. It's important that the small hole is towards the top of the rib.

After drilling, I noticed that it could of been a bit closer to the center bead.

Will do that on the left tank rib.










The anti rotation clamps are deburred.

No need for now to cleco it to the access plate. There's two versions of clamps where the teeth in the inside circle are positioned differently.










The fuel pick-up tube is cut to lenght. It's made from 3/8" outside diameter tubing. One end is flared with the tool seen in the background. The AN fitting is loosely installed through the plate, the tube nut is hand tightened and torqued to minimum values to determine which version of anti-rotation clamp to use. This clamp will be riveted with tank sealant and the tube and fittings installed because it's not possible to install later.
The inside ring is clecoed to the rib for drilling of the screw and platenut holes. All is deburred then the rib rivet holes are dimpled and the ring is countersunk to fit the dimples.














The ring, rib and platenuts are riveted together. Notice the offset ring from the rib. I need to better centre the plate on the left side. I don't believe the offset is a problem, I'll see later.














Just for fun, the root rib assembly. The tube still needs bending which will be done after the anti-rotation clamp is riveted.





Under the skin, the fuel cap flange is clamped and the cap is used to centre it all.

The fuel cap flange is then drilled. The flange will be countersunk and the skin dimpled for flush rivets.


The tank vent line needs a bracket to hold it up that will be riveted with the fuel cap flange. It's made from stock aluminium sheet cut 1 1/2" x 1/2".


These will be curved and bent in a later stage.









The vent line bracket is drilled to the cap flange.















The fuel cap flange holes are countersunk to accept the dimpled skin.















I slightly enlarged the hole in the skin for the fuel drain valve just enough so the actual valve could go through. I then screwed it from inside to the drain flange for position. That centres the drain valve flange and then the skin is drilled.



Final preperations before sealing the tank.

The skin is scored with ScotchBrite pads so the sealant will stick better.

The ribs and stiffeners get the same treatment.

The scored aluminium is then thouroughly cleaned with acetone to remove any pollutants.

The rivets also need a wash in acetone to remove any oils from their manufacturing.

I learned a few things about acetone.

It dissolves latex gloves but not nitrile gloves.

It also dissolves some plastics but not all. I first used a small plastic bottle to wash the rivets. The bottle melted with the rivets embedded in the mess... :-o

There are two commonly used methods for sealing tanks.

One is to butter up the parts, then shoot the rivets immediately.

Then make sure that there's a filet of sealant around the edges.

Finally cover the rivet shop head with sealant.

That's what I did here. It is known to be quite messy and I confirm that. The tools also need to be cleaned almost after each rivet which is time consuming.


The second method also requires to butter up the area and I spread some sealant also on the stiffener.

Then, the parts are installed with 100% clecos.

The sealant cures a day or two until tackiness is gone.



All stiffeners and the fuel cap flange are in place for sealant to cure.







The tank tip rib has a 3/16" tooling hole that needs to be plugged. Instructions call for installing an AD 470-6-X (round head) rivet. I don't have those but I do have some A 426-6-4 (flat head and softer) rivets to repair an error on the vertical stabilizer skin. The rib was then dimpled and the rivet wet set with sealant.










The shop head of the plug encapsulated with sealant.






After 1 day curing, the sealant is still a little soft and tacky. Remember that my workshop is unheated when I'm not there and it's about 8 or 9° C.

I waited an extra day and the sealant was drier while still being soft. It's easier to remove when the tackiness is gone.

Make sure the dimpled hole is free of partially cured sealant. I use a clean brochette stick to scrape it off followed by a wipe with acetone.

I then use another brochette stick to put some fresh sealant on the recess in the hole. That's to seal the rivet head.





The 3 holes, left centre and right, are ready to receive their rivets.












The rivets are pushed in tightly with a stick.

Sealant is squeezed out and seen forming a bead around the rivet head.











After back riveting, this is the "only" mess made. The other clecos are removed.












The rivet manufactured heads after riveting and cleaning with acetone. It can be cleaned at the end of riveting all stiffeners while the sealant is still fresh as it's easier than when it's hardened.


All stiffeners are now riveted and the shop heads are encapsulated with a blob of sealant.

I really believe this method is simpler, faster, cleaner and less frustrating than the "all wet" method.


More details on this alternate method of sealing tanks can be found here.

Using the same method as for the stiffeners, the rib and the skin gets a coating of sealant.













Once the rib is in place and clecoed, a filet is formed along all edges and left to harden for a couple of days.








The fuel cap flange and vent line bracket is sealed to the skin.

Some cleaning will be done before closing the tank.

One note on the vent line bracket. It was very difficult to insert the vent line because of the bracket was already rolled.

Next tank, I will only partially roll the bracket, install the vent line then roll it fully.

A hole is drilled in the inboard rib to install the vent line fitting.














Inside the inboard rib, the access plate flange is sealed and the blue fitting is ready to receive the vent line. It will provide air to the tank as fuel is burned.












The vent line is fitted to the fitting. It's offset from the holes in the ribs so a couple of bends are required.















At the outboard end, the vent line is held by the small bracket and bent to be closer to the top of the tank. The holes in the ribs will be equipped with bushings to prevent chaffing between the vent line and the rib.



It takes me on average 3 minutes to install a tank skin rivet.

Steps includes removing the cleco, cleaning the hole, putting fresh sealant, pushing in the rivet, cleaning both sides of the rivet and bucking.

It took me just under one hour to drive these 17 rivets.












The inside look. Later, there will be a blob of sealant put on each rivet head.




After the fuel drain valve was sealed, I noticed that the countersinks were too large for the indicated size 3 rivet.

The rivet head is recessed in the hole instead of being flush to the surface.

These countersinks were already made on the flange from the supplier.

After measuring, I found that a size 4 rivet would fit nicely.

That would mean to drill the flange and skin from 3/32" to 1/8".
After receiving Van's OK to drill the flange's holes to size 4, it was done and the appropriate rivets installed.

After checking with the rivet gauge, instead of 426 3-4, I installed 426 4-5 rivets.

Here, they received their blob of sealant.









The outside of the drain flange with the now bigger, size 4 rivets that fit flush with the surface.





All 5 inside ribs and the fuel drain flange are now riveted.

Here the bottom of the tank.















Here the top of the tank with the fuel cap flange.















Seen here is the outboard end of the tank.

All the shop heads are now "blobed" with sealant.

The vent line is installed with its plastic bushings











The inboard end of the tank with the vent line installed and the plastic bushings.

On top is the fuel pick-up I made from tubing and fittings.

The end is clamped and a saw is used to cut openings in the tube for fuel to enter.

I wasn't satisfied with the cuts, I felt it weakened the tube.



Below is the fuel pick-up sold by Van's. The only difference is the wire mesh instead of the cuts. This is what I will install.
Intending to install a fuel injected engine, but not having it yet, I drilled some holes in 4 ribs to install a fuel return line.

Plastic bushings are installed in the rib holes.












The end of the fuel return line is bent downwards. It is in the fourth fuel bay from the root so the warm unused fuel returning from the fuel injection pump will be mixed to cooler fuel far from the pick-up point.














The inboard end of the tank with the vent and the fuel return lines.
WARNING TO BUILDERS!! THE FUEL PICK-UP TUBE IN THIS PHOTO IS ORIENTED THE WRONG WAY!! IT SHALL POINT TOWARDS THE REAR OF THE TANK CONTRARY TO HERE.













The tank attach angle bracket is riveted to the inboard rib and stiffener plate inside. The rivet heads get a blob of sealant inside and out.














A view of the inside inboard rib with the stiffener installed. Also seen are the two tube fittings sealed and torqued.











WARNING TO BUILDERS!! THE FUEL PICK-UP TUBE IN THIS PHOTO IS ORIENTED THE WRONG WAY!! IT SHALL POINT TOWARDS THE REAR OF THE TANK CONTRARY TO HERE.

Prior to closing, the access door with the fuel pick-up tube and the fuel level sender are position tested. All looks OK.






WARNING TO BUILDERS!! THE FUEL PICK-UP TUBE IN THIS PHOTO IS ORIENTED THE WRONG WAY!! IT SHALL POINT TOWARDS THE REAR OF THE TANK CONTRARY TO HERE.

The access plate gets platenuts installed that will hold the fuel level sending unit.

The top 3 are sealed and the bottom 2 will get the same treatment of course.

Preparing the fuel tank baffle by scoring the surfaces that will get sealant.
















Laying a bead of sealant just forward of the rivet holes and along the end ribs just inside of the rivet holes.

Also, big blobs of sealant are laid in the 4 corners and the rib rear flanges are layered with sealant also.

I used a big syringe with a 5/32" hole.

A little less than 100 grams of sealant was needed to fully prepare this step.












The baffle gets a thin layer of sealant also around the rivet holes that meet the ribs.












The baffle is installed and the sealant bead between the skin and the baffle looks good!!
Where the Z brackets will be installed, the baffle surface is scored and cleaned.

A coating of sealant is applied.












A coating of sealant is also applied to the Z bracket that was scored and cleaned.














After the blind rivets are twirled in sealant and installed.

There's already a nice filet forming around the Z.

And nice filet around the rivets.











For extra peace of mind, the rivet heads are covered with sealant.









The Z's are all installed and sealed.

The fuel tank baffle being riveted. The bottom skin is done, about half of the top rivets are done.
WARNING TO BUILDERS!! THE FUEL PICK-UP TUBE IN THIS PHOTO IS ORIENTED THE WRONG WAY!! IT SHALL POINT TOWARDS THE REAR OF THE TANK CONTRARY TO HERE.

The access plate is scored and cleaned, ready to receive sealant then screwed to the tank.









WARNING TO BUILDERS!! THE FUEL PICK-UP TUBE IN THIS PHOTO IS ORIENTED THE WRONG WAY!! IT SHALL POINT TOWARDS THE REAR OF THE TANK CONTRARY TO HERE.

The inboard rib gets a good bead of sealant while the access plate gets a coating of sealant.

I chose to not use the supplied cork gasket but only sealant.








The plate screwed on the tank.

I will continue the small bead around it for peace of mind.











The fuel level sender gets the same treatment as the access plate.













The fuel tank is now completed!!!

Only a few blobs and beads of sealant to do before the leak test is done when the sealant has completely cured.










The leading edge parts are drilled, deburred, dimpled and scratched for priming.

Next step will be to cut out the skin for  the landing light lens.
A fellow builder noticed that my fuel pick-up tube was installed the wrong way.

According to the drawing of the plans, it's very clear: the fuel pick-up tube shall be rearward.

For some reason, I installed it pointing forward...

Here, I removed the 12 screws despite them being in sealant for 3 days.

They unscrewed fairly easily as the sealant was not yet completely set.




The access plate was needed a little more persuasion to leave the inboard rib.

I used a pin punch to break the bead of sealant then the same pin punch and some flat screwdrivers to gently pry open the plate.

THE FUEL PICK-UP TUBE SHALL POINT THE OTHER WAY, PASSING UNDERNEATH THE SENDER UNIT.






After removing the plate, the 2 rivets holding the anti-rotation bracket were removed leaving shavings clinging to the not completely cured sealant.

Some cleaning is in order.












After the removed rivets, the bracket itself was un-pryed from the plate.

This was the toughest to do as the bracket was sealed a few weeks ago and the sealant was very tenacious plus the fact that the bracket was restricted in movement also by the AN fitting...








By chance, when I ordered my wing kit, I had some sealant stripper shipped with the lot!!! :-)















The access plate gets a good splash of sealant stripper to help the with the cleaning. Care was made in not getting some stripper gel on the sealed platenuts.












The inboard rib after cleaning.

















All parts cleaned, ready for installation, part II.
















The fuel pick-up tube now pointing in the correct direction, riveted and sealed once more!!!















The access plate and rib with sealant, ready for final closure.












The access plate now sealed and installed for the second time, this time with the fuel pick-up tube correctly positioned.
The template for the Duckworks lens is taped in position on the leading edge.















The rough cut of the leading edge skin was made with a Dremel tool.
















The final cut & polishing were made with some files and a small ScotchBrite wheel.
Retaining strips are clamped the skin for drilling














With a template, 2 marks are made on the 2 ribs around the light.














The 4 holes drilled.














Platenuts are clecoed to drill there holes.














The platenut holes done and the centre holes are enlarged to 3/16" or drill number 12.














The ballast clamped to drill holes in the mounting plate.





The plexiglass lens is marked using the hole in the leading edge leaving about 3/4" on top and bottom while leaving about 5/8"on the sides.











A careful cut with a Dremel is made just outside the marked line.



Difficult to take a photo of something transparent. This is just to show the edge of the plexiglass lens after careful preparation using a file then 80, 150 and finally 400 grade sanding paper.











A handle is made with tape to pull the lens tightly inside the skin. Then a first hole is drilled through the existing hole. A warm lens, slow speed and some Boelube to prevent cracking.














Once the 3/32" holes are done, the lens is removed, everything is cleaned up and re-installed to carefully enlarge the holes to 1/8".













Using a Unibit, the lens holes (not the skin) only are enlarged to 5/32".















A dimple for a no. 6 screw is made on a piece of scrap. It is used to check the countersinks made in the lens.
The retaining strips get countersinks for the platenuts and the screw holes enlarged to 5/32".













The skin holes are dimpled using first a 1/8" rivet die. This enlarges the hole slightly to permit using the no. 6 screw die afterwards. If not, the 1/8" holes need to be slightly enlarged with a drill bit before using the no. 6 screw die.












Checking the fit of the screw in the hole.
All the leading edge and the landing light parts are primed and ready for assembly.












The two most outboard ribs get platenuts for the light mounting bracket. Since I had easy access, I countersunk the rivet holes to install 426 flush rivets instead of the blind rivets. The two retainer clips get also their platenuts and the top one is trimmed and touch up with primer to better fit the lens.












The wing top skin edges and holes are now deburred scored and dimpled. Here the doubler plate.
The wing spar gets countersink holes for all the rivets that will hold the skins. There's quite a few. All rib holes are deburred.













The countersinks get a dab of primer. The rib holes are now dimpled.















The splice plate between the leading edge and tank is primed, dimpled and gets platenuts for screws that will hold the tank.
After priming, the top skins are clecoed to the wing frame. Normally this is done after the leading edge assembly is riveted to the spar.
The leading edge skin is now riveted to the ribs.
The mounting plate for the landing light is installed.














The retaining plates are glued to the lens with double sided tape.














The lamp is installed to the mounting plate.















The electrics behind the mounting plate. I still need to properly attach the wires together and to the structure.













The lens is installed. Not seen is a foam strip between the lens and skin. The light is not lit, it's the reflection from the camera flash. There still needs to properly adjust the light orientation when the wings are on the fuselage.
The inboard top skin is riveted.

Normally as per the instructions, the tank should be installed beside the leading edge.

I had a bucking partner to help in this task.

I can't see how one can do this alone with the tank installed.

There's 2 small recesses on the top left because I forgot to turn down the pressure on the rivet gun after using the squeezer.
Lesson learned...
The fuel tank is pressurized to about 1 PSI only.

A balloon is fitted on the fuel return line while all other openings are sealed.

The balloon will act as a safety valve to prevent over pressurizing the tank.

Then, some soapy water will be used to find if there's any leaks from the rivets, seams or elsewhere.


After 2 soapy water tests showing no leaks, I left the pressure in the tank for fun and 5 hours later, the balloon was unchanged!!!

I declare this tank leak free!!! :-)

The tank is installed temporarily to check its fit and to strengthen the whole wing structure.

Only 1 of 2 screws and 2 of 3 bolts are used for now.

The electrical sleeve tubing is installed through the ribs. The tube is slightly oversize so it takes some twisting, pulling and persuasion to get it through the holes.

For ease and efficiency, I started in the middle rib and worked my way towards the root of the wing for one end of the tube and towards the tip for the other end.







The tube is installed.

 It's somewhat easy where the ribs are spread apart but quite hard and slow to do where the ribs are close together.

I left about an extra 45 centimeters of tubing sticking out on each end of the wing.
The tubing is now installed through all the ribs
The top skins are now completely riveted. Some cleaning will be done, especially on the leading edge as there's some primer overspray.
Back to work on some new parts, here the right aileron brackets are being prepared.
The aileron brackets are primed and riveted. The dirt marks are from the handling during riveting and will be cleaned.
The wing, on its stand, is moved outside the garage for a U-Turn so I can lay it on the workbench top side down to continue working on it.

The skins are now cleaned from the primer overspray and they look better!!









The bottom of the wing ready to re-enter the shop for further work.
The outboard aileron bracket now riveted to the spar and outboard rib.

Notice the bottom (seen on top since the wing is upside down) flush rivet. It's clearance for the aileron it seems.

Again, The bracket looks awful since I touched up the primer after riveting with dabs of another primer batch instead of the rattle can. If It gets to me, I'll masking tape everything up and re-spray the bracket...




The inboard bracket (also with the ugly primer touch-ups). Once more, notice the lone flush rivet.
The flap brace is installed on the rear spar.
































The aileron brace is riveted to the rear spar and the top wing skin. Here, a detailed photo close to the outboard aileron hinge.
















The aileron brace is riveted to the rear spar and the top wing skin. Here, a detailed photo close to the inboard aileron hinge.
The bottom skins are temporarily riveted to the wing.



Seen here is the outboard skin.












This is the inboard skin.
The 3 access openings get their holes drilled, dimpled and countersunk to accept the platenuts that will be installed underneath.













The access plates are now screwed in place. The temporary rivets holding the skin to the wing can be seen on each side of the plates.

There is one in every fifth hole. The wing, without the aileron and flap, will now be stored so that the other one can be completed.
Work on the left wing has resumed. During this step, I will present less photos since it's mainly a repeat of the right wing's work so I'll show only the big steps and anything that's different or interesting.

Here, after the ribs were washed, etched and primed they are riveted to the main spar.


A close-up look of the rivets.

As they were driven while the spar is on the work bench and not on the stand, the result was good and I didn't have to remove any contrary to the session on the right wing.



The left leading edge will have a mechanical stall warning device.

Here, the access hole, its panel and doubler are all ready for priming before riveting the platenuts.


The stall warning mechanism and electrical stuff will be held together with this small riblet.

It needs to be fitted and match drilled to the skin.

The lower flange is not at 90° with the skin.




A couple of pilot holes are enlarged and the skin between them is removed.

Here, only a rough cut is made.
The small opening is done, only some deburring to do.
Here is what basic wing work looks like.

The left wing with its leading edge on the stand with the skins and ribs all match drilled.

That's just under 1400 holes that will be deburred and dimpled later.



The tank brackets are all redone in the alternative way from the plans.

All bolts were a breeze to screw in through the spar which is a good sign.




The tank is now assembled, drilled and fitted to the wing structure and the attach plate of the leading edge.
All left tank parts are now drilled, deburred, scored and ready for assembly with sealant.
Construction continues on the left tank.

The 5 internal ribs are sealed riveted.

The vent and return lines are done.
The fuel return line, its end is in the third compartment in the middle of the tank.

The vent line seen at the outboard end is at the highest point in the tank.

Installing the end ribs is now the next step.
The fuel tank access plate and its sender are now prepared before installing the rear baffle.
The tank is now complete and brought home to let the sealant cure a few days before the pressure test. Some cleaning of sealant is still in order.
Working on the leading edge assembly, the stall warning riblet and plates are drilled, dimpled, countersunk and primed.

The riblet will later be fluted for a better fit (seen in a further photo).

These 2 plates will hold a micro switch and an aerodynamic vane.

Platenuts seen here are for bolts that will hold the assembly to the riblet.



The micro switch & the aerodynamic vane installed between the 2 plates.
The assembly seen from the other side.



The leading edge has an access plate for the stall warning assembly.

This is the doubler plate, primed, fitted with platenuts and riveted to the leading edge skin.



The riblet is riveted to the skin.

The web had a curve as if it was too long so a few flutes were needed to straighten it.


The micro switch and vane assembly is attached to the riblet.

A ground wire connects the switch to the riblet and another wire will be installed to feed the audio warning in the cockpit.

Primer was removed on the riblet where the bolt is fixed and also between the riblet and the skin ensuring a perfect electrical contact.

I still need to tighten the bolts holding the assembly to the riblet as I only have metric Allen keys for now...



The aerodynamic vane sticking out the front of the leading edge.
As for the right wing, the left wing leading edge also gets a landing light.
Here we go !!!

Work on the ailerons starts with trimming stiffeners.

The construction technics are similar to the empennage. There are 8 long aluminium angles to cut in 4 short stiffeners.

Seen here are the first 4 made from the bulk stock.



A closer look of one stiffener freshly cut.

Further trimming and polishing will follow to ensure smooth edges all around.
The 32 stiffeners are roughly cut.

Unfortunately, on 2 occasions, I strayed with the shear cutter and cut the flange too thin.

See next 2 photos.
The middle stiffener, after smoothing the edges, is one of the 2 that I messed up.

On the bottom is what it should be like.

I believe that it will not be stiff enough and maybe flex a bit.

The top one will be used as a doubler.


To strengthen the stiffener, I doubled it with another, unused stiffener from the elevator kit (I mistakenly cut a few of them too short and had to order new ones).

I match drilled the holes and the now doubled stiffener seen on top,  will more than strong enough.





The stiffeners are all clecoed to the aileron skin, ready for drilling.

There are 7 holes per stiffener.
Be wary that the aileron spars are assymetrical.

The top and bottom flanges have different angles and a different hole pattern.

As the plans say, the 3 closely spaced holes identify the bottom flange.


Both spars need to be correctly oriented and identified.







4 reinforcement plates are made as per plans from stock 0.040" thick aluminium.
A reinforcement plate is clamped and will be drilled using the spar as a template.
The plate is now drilled and the inboard aileron bracket is installed for further drilling.

NOTICE TO BUILDERS: There's a wrong part number on the plan for the inboard bracket. The plan says A-407-R instead of L.

See 2nd further photo.

The outboard aileron bracket is ready for further drilling to a no. 12 size drill bit. The brackets will be attached using AN-3 bolts.
NOTICE TO BUILDERS: There's a wrong part number on the 13A plan concerning the LEFT aileron.

It calls for the inboard aileron bracket  being A-407-R.

Everywhere else on the 13A plan, this part is refered to as A-407-L.

It got me spinning for a while, but when respecting the 3 hole orientation and keeping the rounded end towards the bottom, only the L fits correctly.

Unless I missed something... Van's was advised of this possible error and I asked for clarification.
The aileron nose and main ribs get drilled to the spar and to the front and rear skins.
The ailerons require a counterweight to prevent flutter and for balance.

The ends need some work to remove the saw marks.

They are made out of galvanized steel tubing and weigh 1.6 kilograms or 3 pounds, 4 ounces each.


The steel tube counterweights are fitted and clamped to the aileron nose skins.
The steel tube is  now drilled, using the skin as template.

It will be held in place with pulled rivets.
Meanwhile back at home, the left tank is under air pressure. I went outside for the soapy water test.

Here's a closeup of the inboard side, and how I plugged the 3 outlets.
On the left top, I screwed on a closed fitting.
Just below, I fabricated and installed a flared tube with a closed end.
On the right, I fabricated another flared tube, this time with an open end were the balloon was installed.

The balloon serves as a safety valve to prevent over-inflating the tank.
It's encouraging that my tubing flares are done well enough to be leak free!!
It was checked all over and no leaks were found.

Even the fuel cap (Deluxe locking seen in the lower part of the photo) was airtight.
Back to the ailerons, here is a close look of a hole in the galvanized steel pipe that acts as a counterweight.

The hole is machine countersunk to later accept the appropriate rivet.
After all aileron parts were primed, it's time for assembly.

First step is to rivet the 32 stiffeners to the 2 skins.
The skins need to be bent further than what is done at the factory.

The wooden bending brake seen in the background is brought out of retirement from being used for the empennage.

After the photo, I did bend the skins just a bit more so they were almost matching the spar's height.
The doubler plates and the platenuts are riveted on the aileron spars.
The nose ribs are riveted to the counterweights with a single blind rivet.
The nose rib/counterweight assembly is then riveted to the spar.

The front skin is only clecoed on for the time.
Then comes a tricky part.

The rear skin is clecoed on top only to leave access to the inside from the bottom side seen here.

This is to rivet the top forward and rear skins to the spar.

I used blocks of foam to keep the skin open so I can access the rivets with the bucking bar.
Looking closely at the middle of the photo, there's a horizontal line of driven rivets.
Once the skins are riveted on top, then the nose skin gets riveted on top only to the rib.
The outboard and inboard brackets are bolted to the spars.





However, I will have to remove and reinstall all bolts as I mounted the washers on the bolt end instead of the nut side... :-P
Here's a good use of water weight and clecos.

They hold the aileron down and keep the skin flat while riveting.
The counterweights are blind riveted through the nose skin.
Apart from removing the bolts, nuts and washers that hold the brackets and reinstalling them correctly, this is the most I can do until the MDRA inspects the ailerons.


On with the flaps now...
The nuts, washers and bolts were removed, then installed correctly...

Don't know what I was thinking when first installed...
Flap construction technic and process is simple.
Spars, ribs and skins. All need to be fitted, drilled deburred and dimpled like many other components.
One difference is the piano hinge.
It needs to be cut to 56 inches from the stock 6 feet lenght. Then it is positioned and drilled to the spar.
One thing to note is that the 2 most inboard spar holes are NOT covered by the hinge.
The main challenge here is to keep the hinge as straight as possible at all times.
The skins get dimpled while the spar's lower flange gets machine counter sunk so that the hinge rests flat on the opposite side.

I used a small vise to hold the spar while machining the spar.

Long story short: this vise is over 30 years old, made by myself with aluminium blocks with steel rods and blocks in a school project while I was studying aircraft airframe mechanics. I sadly didn't complete the diploma but kept the vise and other construction techniques.
Seen here are the two most inboard holes on the spar.
As there's no hinge underneath, the holes are dimpled instead of counter sunk to accept the dimpled bottom skin.
Both flaps  need stiffening angles.

2 are made from stock aluminium.
The 2 angles done as per the plans.

All the edges are polished and rounded with the Scotch Brite wheels.
These 2 plates have to be bent where the vertical lines are drawn.

The plans call for a 6.3 degree angle.

For starters, I used my drawing from the Horizontal Stabilizer plan where a 6 degree angle was needed then made some small adjustments for finish.
I put the plate between blocks to guide the bend but after attempting to fold with a rubber hammer, the wood was too soft.
So I then installed in the big vise my smaller one that have smooth metal claws.
Testing the fit after the bend.

The angle looks good !!
Oops...

For the second time (see the Vertical Stabilizer), I did a figure 8 with the dimpler...

Again, I enlarged the spar and skin holes to 3/16 and dimpled accordingly.
Clamping the angle and the plate together on the spar and rib to adjust for drilling them together.
Again using my small vise to hold the plate and ease the critical drilling of these parts.
The angle is now completely drilled.

13 holes in this one part made from stock.
After all flap parts are drilled, deburred, dimpled and countersunk it's time for priming.

Here are all the internal parts except the spars and the skins.
First rivets on the flaps are these to hold the angle to the spar.

The row of holes for the inboard rib are left open for now.
One little catch here.

At this stage, instructions get pretty basic. Almost like, fit, drill, dimple then prime as needed. Then rivet as per the plans... I exaggerate just a bit ;-)

Nowhere in the instructions is specifically mentioned to set the rivets that hold the inside ribs to the bottom's skin "spar". Just; rivet the inside ribs to the skins.

So these are done first without the top skin installed otherwise they could not be reached on both sides.

Pulled rivets could be used here if both skins were riveted beforehand.
Before going further, I drilled the end plates to the inboard ribs.

The platenuts holes get countersunk on the ribs and the plates and will receive different lenght rivets.
The plates and platenuts are now riveted to their respective ribs.

Do not rivet these assemblies to the spars yet as there will be no access to rivet the ribs to the skins.
Next step is a bit challenging as I have relatively quite large hands.

Ribs and flap skins get riveted together.

I used a small tungsten bar inside and the rivet gun outside.

I finished with bruised knuckles from rubbing my hand inside the flap skin.
Once the inside ribs and skins are riveted together, the inboard ribs are riveted the same way.
The spar needs to be off also for this as the rivets are not accessible from outside as seen on the flap on top.
6 pulled rivets are used on each ribs near the trailing edge.

Then the outboard ribs are riveted with the squeezer except for the ones nearest the trailing edge where the rivet gun and a modified (thin) bucking bar are used.
The Spar is now temporarily riveted for removal later to permit the flap inspection.

The piano hinge is also temporarily installed.
A view of the complete left flap.

I now have installed more than 5000 rivets. Since the sub-assemblies all have temporary rivets, that number should be higher at this stage.
Building the aileron pushrods is the next step.

A powder coated steel tube is cut to size, 23 inches and 13/16, to obtain two small aileron pushrods.

These will later be connected between a bellcrank and the ailerons.
A larger diametre aluminium tube is cut to 69 inches and 3/16.

This pushrod will be connected between a bellcrank and the cockpit control stick.
The pushrods are cut and the ends are deburred.

On the left are the 2 leftover tubes from cutting the pushrods.
After priming the inside, threaded inserts are hammered in the 2 small pushrods.

The fit is very, very tight.

USE LUBRICANT AND DON'T TAP TOO HARD ON THE ROD ENDS, YOU RISK DAMAGE TO THE FIRST THREADS.

Guess how I found out...
Using a little Boelube makes the fitting of the rod ends easier.

They will later be secured with a couple of rivets each.
A home made bracket is used to hold the small pushrod for drilling.

3/32 inch pilot holes were first made then enlarged to 1/8.
Rivets, locknuts and end bearings installed.

On one of the threaded rod ends, I had to cut off about 1/16 inch  and tap the thread at the start because of my too intense hammering had flattened it and I could'nt fit the end bearing...

Again, use lubricant and go easy with just enough pressure to insert those threaded rod ends.
The large pushrods also get some threaded ends.

Here they are match drilled together.
These are the bellcranks that will later connect the two pushrods.

Brass sleeves and AN bolts will hold them to brackets on the main wing spars.

The bellcranks and sleeves need just a touch of reaming so all parts fit nice and snug with no gripping or looseness.

I used two different sizes of round files and a little elbow grease for this.

The bellcranks and the brass sleeves will need to be shortened a little to fit correctly between the wing brackets.
All the aileron bellcrank hardware are prepared for installation on the wings.

This involved cutting the bellcrank's tubes and their brass bushings to fit between the wing brackets.

The brass bushings are kept about 1/32 longer than the bellcrank. Two small aluminium bushings are also made from stock tubing.

All bolt holes are final drilled to size.
After priming inside and out, the rod ends are riveted and the bearings are threaded in to the plan's call of 72 inches and 11/16.

These will be adjusted more precisely when the wings are installed on the fuselage.
The top inboard skin of the left wing is riveted.

I mostly used the back riveting technique with the long neck on the gun except for the top row of rivets where I used the normal way.

The most inboard row and the bottom row of rivets were set using the squeezer.

I used longer (4) rivets on the bottom row as the (3.5) lenght as per the plans is, in my view, a tad too short. The longer (4) rivets form a much better shop head.
The top outboard skin is riveted except for the top row.

The tank is removed because the most forward rivets that attach the ribs to the spar were forgotten.

These should be done when the ribs are first riveted to spar.

See next photo.
Here are the missing rivets holding the 8 most inboard ribs to the spar.

They are underneath the tank skin and not accessible when the tank is in place.

Don't forget to rivet both the top and bottom flanges of the spars.
The left leading edge was also removed to have better access to the stall warning assembly.

Final adjustments to the vane and the micro-switch were done and the wiring was also completed.
The aileron bellcrank is installed (seen here bottom up).

The top spar bracket (seen on the bottom here) needs to be removed to insert the longest bolt.
Don't forget to grease the brass bushing before closing the wing.

As a standard safety practice, the bolts are installed with their heads on top and the nuts on bottom. Remember that in this photo, the wing is bottom up.

Only the small pushrod is installed for now.

Also seen here is the black wiring tube running spanwise, and the stall warning wire sticking out from the spar.

The left wing aileron brackets primed and assembled with their bearings.
The inboard aileron bracket is installed to the rear spar.

I needed to remove the small aileron pushrod as it was in the way of the rivet gun.
The outboard bracket. Seen again bottom up, where there is the flush rivet (topmost on photo) I deepened the countersink for a better fit.

Some extra primer was used from a previous batch, hence the color difference.

Also, the rivet below the flush one is installed opposite the others with the manufacture head on the outside. For some reason, when the manufacture head was driven on the inside, the rivet gun jumped and damaged the head. I tried 3 different times with no change.

Out of despair, I drove it on the outside and it went well. Afterwards, after thinking about it, maybe there was too much air pressure in the gun.
The left aileron brace installed to the rear spar and top skin.

The small pushrod is back in its place but not yet bolted to the bellcrank.
The left flap brace (seen again top side down) is installed permanently to the rear spar and temporarily to the bottom skin.
After installing the bottom skins with temporary blind rivets, it's time to prepare the access plates once more.

The 4 holes nearest the fuel tank get drilled and dimpled to accept a number 6 screw while the rest gets drilled and dimpled to accept bigger number 8 screws.

Notice the black clecos used for the larger holes.
The wing skin is prepared by dimpling the large holes and countersinking the small holes that will receive rivets holding the platenuts.
The 3 access plates are all drilled and dimpled.
The platenuts are now installed under the skin.
The access plates are now screwed in place.
This is not Van's standard pitot tube installation. Night or IFR flight require a heated pitot, seen here on the right.

In the middle is the mounting bracket or mast.

My plan is to install the pitot just outboard of the aileron access panel seen on the left.

As the pitot needs to be perfectly inline with the airflow, I started by using 2 screws from the access plate and a ruler to draw a reference line parallel to the wing spar.

I will also fabricate and install a strenghtening doubler under the skin. It will be riveted to a rib, the skin and the spar.
Next is to align the front mast holes with the reference line.
The outline of the bracket, its holes and the mast are drawn on the skin.

The mast is actually bigger than the drawing so this is just to start the hole.

The first hole is made. The 4 holes will be dimpled to receive no.8 size screws.

The mast was used as a drill pilot.
Using a Unibit, holes are made to start the mast cutout.
Putting the bracket underneath the skin, I used it as a guide to enlarge the mast hole to its inner limit with a Dremel tool.

Further trimming using different files will make the hole to its correct size and shape.

Disregard the additional green line around the hole, it's there for nothing...
After filing away little by little, the mast is starting to go through.

More filing is needed to ensure a better fit.
The mast hole is now done.

This is the finished look.

Next step is to fabricate the doubler that will strengthen the whole assembly.
To make the mast doublers, I inspired myself with a few fellow builder's solutions.

I used two pieces of flat stock aluminium. One has a bend so it can be riveted to the rib while the front end will be riveted to the spar on the opposite side of the wing skin.

The smaller but thicker plate will compensate for the spar's thickness.

Here, I'm positioning the bracket against the rib and the spar to drill the front holes using the spar as template.
Next step is to drill the screw holes by clecoing the bracket to the skin and using it as a template.
The bracket in place to draw the mast opening through the skin.
Using a Unibit and the Dremel tool to start the mast hole.

The hole was enlarged slightly wider than the line to make room for a small shoulder between the mast post and its flange so the bracket will sit flush to the mast flange.
Platenuts holes are drilled through the mast flange.

Drilling chromed stainless steel is more demanding compared to drilling aluminium.

I used a new drill bit and lots of lubricant.

Countersinking for the rivets and screw heads on the other side was also tougher of course.
All parts dimpled, countersunk and drilled.

Notice the small fluting done on the bracket flange. This is done to match the curve in the wing.

I drilled both plates to flush rivet them together.

At first, I didn't consider the mast flange so I had to drill new holes.

No matter, the unused holes can be considered as a weight savings of a few micrograms.
Platenuts on the mast.
Platenuts on the mast, flush side.
The two doubler plates are riveted together.

The bracket is positioned for drilling the rib.

To ensure a perfect fit, the skin and the pitot mast will be installed prior drilling.
I marked approximate hole positions on the rib.
The pitot mast is screwed in and the bracket is clecoed to the spar to ensure a tight fit of the bracket to the rib.
Needed here is the angle drill.
The rib with the bracket holes.

AN 470 AD4-4 rivets will hold the bracket to the rib.
The matching 1/8 inch holes in the bracket.
Had a "duh" moment one recent night; the 0.032 inch doubling plate on the bracket is not thick enough for the spar's flange which is 0.063 inch.

The nice thing about aluminium is it's easy to work with or repair...

The rivets holding the doubler were removed and a second 0.032 plate was trimmed to size.
Using the first plate as a template, the second plate was drilled, dimpled and the mast hole was cut.
The two 0.032 inch plates are fixed to the bracket and all is primed.

The 0.064 thickness now matches the spar's 0.063 thickness.

The three holes on the bracket's flange will be abandoned as they are now misaligned to the rib's holes.

Fortunately, ample space still exists to drill new holes. They will be done when the wing is final assembled.

For stiffness, doublers will also sandwich the rib and bracket when riveted.

The 5 holes attaching the bracket to the spar were undimpled as it's not necessary.
To free some space in the garage/airplane factory, I moved the empennage parts and wings to a storage facility near my home.

The wings are stored upright on their outboard ends, resting flat on a 5 inch foam mattress. They are safety tied to the building's roof structure.

The horizontal stabilizer is resting against the left wing.

The other parts of the empennage are not seen in this photo but are also resting on the mattress.
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