The first process is scuffing. The best is to do this after deburring, but before dimpling. The dimples will wear your scuff pads down very quickly.

I use either Scotch-Brite Hand Pad 7447 or the Colad scuff pads. You can clearly see the difference between the scuffed aluminum and the unprocessed aluminum.

The reason to scuff up the aluminum is to make the primer stick better to it. Although I tried on practice parts to prime unprocessed alubinum and the result were also very good. However the consensus is that scuffing is better, so I’ll stick to that.

On many places the top skin overlaps over the side skin, so on these locations I remove the blue vinyl and scuff, degrease and prime these parts too.

I found a small strip on the tail side skin that also overlaps, hence I have to prepare that part also.

I use the KRISTAL Aqua degreaser 3000, to cleane up and degrease the aluminum after scuffing. I apply the degreaser with Colad (glue free) degreasing towels, while wearing Colad disposable nitrile gloves.

For priming I use the Sikkens (Akzo/Nobel) Washprimer 1K CF combined with the Sikkens Reducer (2 to 1 ratio). Although it’s just a single component etching primer, I’m really impressed by the results and the ease of spraying it.

Time: 3 Hours, Rivets: 0/0 (2019-11-27)

Time: 4 Hours, Rivets: 0/0 (2019-12-01)

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The main reason is to cleanup the parts and to prime them. I start by removing the firewall.

With the firewall removed, you can now see all the longerons and stiffeners that were added on the forward side of the center section.

Carefully I’m disassembling the bulkheads and stiffeners.

After those I can also rewove the longerons. You can see all the drilling debris on the bottom skin.

With all the bulkheads, stiffeners, longerons and the bottom skin removed, the construction becomes very fragile again.

Now I have to remove the side skins and that looks like I go back in progress a month of two.

After separating the center section from the tail, I start counter sinking all the parts. so the counter sunk holes are also primed.

It’s kind-of a puzzle what part to dimple or counter sink. The main rules are: don’t counter sink thin materials (e.g. skins) or structural parts (longerons), don’t dimple anything over 0.04″ (because it won’t work). Thus leaves you in some places with a catch 22.

If you can’t counter sink skin and can’t counter sink the longeron, how about the side skin top row on the main longeron?
The trick is that you can counter sink skin if it is covered by another layer of dimpled skin.

So here I’m counter sinking the bottom skin of the center section, because it is covered by the bottom skin of the forward part. You could also counter sink the flange of the main bulkhead, but I don’t like the idea of drilling in the main bulkhead.

I want to create a new workspace for the fuselage, once the tail and center section are riveted together. So I’m moving the tail to the same table next to the center section.

I dimple the extra row of rivets that were drilled with the side skins.

I use an old ladder on my adjustable table and cover it with some MDF plates I had left over.

This creates a strong 4 meter construction that can hold the entire fuselage and makes it real easy to work on it (I hope).

Time: 3 Hours, Rivets: 0/0 (2019-11-20)

Time: 3 Hours, Rivets: 0/0 (2019-11-23)

Time: 3 Hours, Rivets: 0/0 (2019-11-24)

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This post combines the priming of the wing ribs and riveting the rear spar components together.

Here’s the result of the rear spar doubler plate in the middle. The strange shaped hole is actually correct and it should accommodate the movement of the aileron push rods.

This is the rear spar inboard side with several doubler plates. The holes that are not riveted are used for attaching the ribs.

Primeing the ribs I did without the help of my daughter. I only have one face mask and even if I had two I wouldn’t allow my little girl to enter the spray cabin. It smells too toxic to be careless with.

Time: 6 Hours, Rivets: 113/7

During scuffing and degreasing (let’s call it cleaning), I remembered that I should first scuff then dimple and after that degrease. Now I just wear the Scotch-Brite pads for no reason. Degreasing is also better after dimpling, but I probably grease the skin up again.

Last step before Priming the Elevator parts is the preparation of th paint. I use the light-green, one component self-etching wash primer (Sikkens Washprimer 1K CF) and mix it 2:1 with a reducer (Sikkens Reducer). This combination keeps the paint workable for at least one hour.

I definitely get better at my spray paint gun handling, but I’m still not satisfied. Although the result is not bad.

One improvement is increasing the work light while painting. Especially after spraying for 30 minutes and not having a professional air vent system, it get’s harder to see the result while spraying. Next time I’ll experiment with construction lighting, although this could produce shadows, so some experimentation is necessary.

Time: 4 Hours, Rivets: 0/0

Video

First step is cleaning (specifically de-greasing) all the parts (both ribs and skin). The nice part is I can do this while sitting on my stool.

I tried to make a video of the priming process, but It was mainly my back, so I clipped it short.
Using the paint spray gun is an art and I don’t have that skill yet. But the quality is sufficient for the inside of the plane.

According to some builders, priming is useless and just adds weight. Others claim it is a necessity in some climates. Well I think it looks great.

After priming, I can start again with cleco-ing the spars and riveting the spar doubler and hinge brackets of the rudder to it.

Very productive day, next session I can probably finish the vertical stabilizer and start with the rudder.

With this progress I have to start thinking on ordering the wings. I thought I would do this in 2018, however with the 8 weeks lead-time of Van’s Aircraft, I might run idle.

Time: 5 Hours, Rivets: 115/2

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