Willy Nillies Cub to Citabria makeover

Ok, so this is my first posting, bear with me. (no, not Bare, you guys keep the clothes on)
I've been posting the updates to the FB page, but figured, I may as well show you guys what I'm doing. So I'll post up to where I am in a blaze of entries.
If you hadn't heard, over on the Willy Nillies Builders page on FB, there is a little contest going on that requires the use of a WN wing as the basis. This will be an "accidental" entry because it just happened. I was already working on a Howard DGA 15. Haha! I'll do another posting for that.
Anyway, I had already printed out the Sterling Citabria plan from Outer Zone at the same basic 250g class size as a WN plane because my intention was to build one from scratch. :)
I had ordered a Cub from WN and it showed up the day I was staring at the planes. Hahaha!
Slipping the Fuselage side out of the package, this is what I found.
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First step of course was to make the addition to the fuselage top. These parts were not made by scraps from the kit.
If you wanted to build yourself a Citabria following what I am doing, you could omit this and just build the fuselage as it came from the kit and reshape the Tail feathers and wingtips. Those steps will make it a nice stand off look alike.
Me? Well I want to go a little further and make the lines more match the actual plane. I take full responsibility for any change in flight characteristics.
 

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For the most part, it will build just like the Cub, I will need to do a little work on the top Fuselage formers for the added height and the movement change of the wing. The change in moment is right with the Sterling plan moment arms, so we'll see that result when it flies
 

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Gluing this piece of scrap back on, going to use everything in the kit, even the scrap.

A little final sanding and covering, work just fine. You can see the kit parts in there. the grain directions of the add-ins give a bit of stiffness to keep it from warping with heat shrink covering. Ta-Da! Rudder and Vert Fin.
And YES! All those pieces were scrounged from scrap in the kit.
BTW, this series of mods could also be used to create a Champ, after all, that's what the Citabria was based on. Change the shape of the Vertical and Rudder, Voila!
 

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Here is the making of the Stab and Elevator changes. The pic order follows my remarks.

I marked out for cuts, taped up cutouts to minimize the chance of breaking a stiffener.

Scrap edges from the kit were used for the leading edges, I left the nubs on til it was glued in place and then trim to size

You can see the Leading edge strips before trim

Finished stab ready for final sanding and covering. Trimmed to length, caps added. Note grain direction to minimize warps and add stiffness.

Elevators start the same way, tape up the loose parts to hold integrity while modifying.

Yup, that triangle getting trimmed for counter balance is from the Stab.
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:) Again ,the piece of scrap glued to the tip.

Finished Elevator halves ready to sand.

Note: there were two types of counter balances used on the Champ/Citabria, I went with the Stab/Elevator style balances used on the Citabria Pro/Decathlon to make them simple.
 

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Wanting the overall visage of the body to look more like a Champ/Citabria, I got busy adding some more mods.
The lower was trimmed 3 1/2 from the wing saddle and parallel with it. I then added the strip to the lower rear. A small section of the lightening hole was glued back in for some integrity. the from area was trimmed from the bulkhead forward as well to reestablish the lower cowl line.

The little closer view of the mod sitting on the plan you can see the match lines
 

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In keeping with the Champ/Citabria mods, I change the thrust line to match the line from the Scale Sterling plan. I used the blank firewall and added the cooling holes, the stock firewall is on the right.
 

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Wanting a little more curve under the nose and cowling area I added some triangle and filler pieces then got to sanding. Kinda early in the assembly for this much sanding but I was also setting up the transition from Cowl area to the stringers in the lower Fuselage as you can see in the background picture.
The second former for the gearbox is in the foreground.

Added some cheek to have a sanding foundation. Do they call this getting "Cheeky"? Ha!
 

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Former for the gearbox, I left the center piece long to trim after I put it in. I wanted to get the cooling holes cut and the thickness established.
My hole cutters in the background.

Former for the gear is installed, the gear will go in later, but I think I captured the bottom detail pretty well. At this point the fuselage weighs 30.1 grams.
Need to build the wing to drill peg locations and wing bolt plate. Coming together Kinda nice.
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:)

That pretty well rounds out the bottom. Maybe...
 

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Still on track, I built the wing but didn't add pics as I went since that is covered pretty well in the PDF and other builds.
Where this deviates is of course adding the Carbon fiber peg. Yup, still using scraps from the kit as noted by the "CUB" lettering. I did glue the lettering as the etching was almost halfway through it.
You might notice that I did some cutting to the Windscreen angle as it was kinda wrong. Note the laser etching line on the inner Fuselage.

A better look at the peg arraignment on the wing.
Another thing you might have noticed is the Aileron holes. I made mount tabs for the servos and the stand up along the spars. All that sticks out is the arm and I cover the hole with clear tape after installing them. The EMax 9251ii 's are so small it's really not a big deal. I just don't like gluing servos in.
 

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Shot from the front with the wing in place. Yes, Top hatch, plenty of room to slip the battery in.

Yes, I decided to cover the nose. Motor fits fine. The battery hatch is on top and the battery slips in fine. with the high wing and the raised trust line I wanted the weight at or a little above so it didn't get a heavy pendulum effect.

There is what I came up with on the upper stringers. It will be a tough cover job, but I'm going to attempt the tail fillet with covering like full scale. Glutton for punishment?
 

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Here it sits all stuck together minus the landing gear so I can admire it and look for things I need to change. Amazing thing is it only weighs 68 grams at this point!

The wing tips...Holy crap! There are several versions depending on the model/year and owners that change them. I settled on this tip. I had some super soft/light block material just begging to be used. They weigh about nothing all carved and hollowed. The tip angles a exaggerated in length, but I like how it looks, the ailerons are strip rather than Barn Door anyway, so deduct points for scale.
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:)
Looks pretty cute at this point, couple small things to do and then I start covering. Whoot!!!
 

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So finally sitting down for the day, I started mulling the decals for my prop(s). I'm also building a Howard DGA 15 and trying to keep it in the 250g class using a WN Q-Tee/S-Tee wing as the base. Each cell prints 8 decals. The picture shows a 6 x 4 prop
I printed two sizes and now need to decide which I like better, so inputs welcomed.
 

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OliverW

Legendary member
I've been following this on FB and you've been doing an amazing job! I'm nervous to start my mini skymaster 😬😬😬