Hello everyone, this is my first post!
Attending the NATS this year reignited a long-dormant interest in flying. Though I enjoy judging, attending contests, and being at the field, flying has never been something I've done with any regularity. With this new found excitement for flying, I decided to start small and build a 1/2A scale plane.

The question was: what do I build? I have basically no experience with 1/2A engines, so I'll stick with just one. Also, I've never built a plane by myself from start to finish, so it should be relatively simple. So that got me to a single-engined, inline-engined (no perfectly round radial fuselages) fighter plane. I decided to go with the Ki-61—a classic. I found a Walt Musciano plan for a .09-sized Ki-61 and sized it down 33%.

My version has a 20-inch wingspan and is powered by what I'm pretty sure is a Cox Super Bee.


The basic structure. It's a twin keel fuselage using 1/8" balsa keels and formers. The fuselage is built around a 3/16" spar with 1/8" braces.


The airframe put together. It has a Perfect 1/2A Bellcrank in it. This photo has a clevis for the pushrod connector but I later had to change this to a ball link for clearance. It's a tight fit in there! The first former is the firewall and made of ply. I fitted as much balsa block as would clear the bellcrank between F1 and F2 so hopefully that's enough.


A view from the top. The wing is sheeted with 1/16".


With the fuselage sheeted with 1/16" as well. A first-time builder's mistake is visible between this photo and previous one: I sheeted the wing before installing landing gear! I cut back into the bottom of the wing, epoxied the gear to the main spar, and then braced with a mountain of epoxy and wood.


One of the challenges of the smaller size is fitting leadouts. The plan called for them running the length of the inboard wing internally, which just wasn't possible in the downsized wing. So now there are two cutouts in the fuselage to clear the bellcrank and also some further down the wing where the dihedral meets up with the height of the bellcrank, and then aluminum eyelets in the wingtip.


The part I was most nervous about: the cowl and canopy! Thankfully since they were so small, they weren't too challenging.




As you can see in the photos, the bottom of the nose is glued to the fuselage. And then the top half can be removed. It's a very tight fit to get to the bottom two screws for the engine mount, but with a skinny screwdriver it just barely fits.

That's it for now. This has been a fun and educational couple of weeks of building.
Jake

Hi Mr. Jake,
I'm digging your build! I especially like the fuselage construction.

While I'm not advocating "stealing a new member from SH," I do want to advertise another site that is heavy in my four site rotation...they'll LOVE to see this plane. Jump over to CoxEngineForum.com. Create an account...watch your spam folder for account validation email. The admin approves using an "admin*" account, which some email systems flag as junk mail.

I use the same username here, on CoxEngineForum and RCGroups. It just makes it easier to keep up with "who's who" between the three.

I'll be watching this one as you continue! Please keep posting your progress.

Thanks for sharing "small!"

I too will watch for the finish of this little plane.   Is this the same Jake that used to draw pictures at a contest?

I got to have a look at this at last weeks contest in Dallas. I have to say Jake is very talented and I would expect this to be a winner at the nats if he chose to fly there. He is good just like his dad.

Dick Byron

We're getting somewhere now.



I masked the tail and roundels and then airbrushed the airframe with Tamiya Mica Silver lacquer, thinned 30% with Mr. Color Self-Leveling thinner. This is what I use for my plastic models, so I figured it'd work here too. I ended up using about 25 mL of paint to cover this little guy. I then masked and painted the ailerons flat aluminum.




Confession: I've built hundreds of plastic models but had never done a Japanese or German squiggle livery. I've actively avoided them. But here we are. I used a smaller point needle in my airbrush and thinned the olive drab a little less than the silver point to avoid runs. I unfortunately had some contamination issues in the beginning and had a few splatters. I later covered them up with even bigger squiggles. Eventually I found a sweet spot: holding the gun 3 inches from the surface (which felt insane to me) and extremely low pressure: just 15 psi. I typically do my plastic models with the airbrush 8 inches away and at 25 psi, so this felt so weird.




But it was all worth it! After the green dried, I masked off the wing roundels and painted them red. I used a very thin coat of primer again there. Red is quite translucent, so I could get a much thinner, complete coverage over the silver and green wing with primer and paint vs. lathering the red on. I then painted the anti-glare panel flat black. Then I masked off the canopy area and painted it a 50/50 mix of gunmetal and mica silver. Then I masked the canopy frame with 1 and 2 mm Tamiya yellow masking tape (it's the best) and painted it again with a light blue I mixed.




I won't lie—I'm extremely pleased with this. I was practically giggling when I pulled the tape for the blue fuselage stripes and say how clean they came out. Unmasking is always my favorite part. I'd like to give a huge thanks to Frank McMillan who gave me some great advice on painting scale planes and even sent me some reference material for paint colors.

Unfortunately there won't be much more to update with for a while! I move to Singapore in exactly 1 week. So this will get a coat of clear to seal everything and then go into storage for a while.

Jake

That’s really nice!
Chris…

I am calling this one done!
The final steps were auto clear, assembly, and finishing the leadouts. Fishing the leadouts through the holes in the top and bottom of the wing as well as the brass tube in the wing was a lot more complicated than I envisioned. But it came out pretty slick.

I've made a couple mistakes along the way (forgot to paint gear doors before clearing it, never finished the gear doors etc.), but I'm ready to fly this thing. I plan on flying it this Friday in the Brodak 1/2A scale contest.

This post serves as documentation of its existence. This is a heavy thing (6.5 ounces) for a tiny little wing. To minimize my chances of complete destruction, I plan on only flying it once before the competition. Mike Londke got my engine working like new. He disassembled it, cleaned some rusty parts, and cleaned the reed valve. It was highly educational to watch him rehabilitate that engine. He also made me some Spectra 28(!!) foot lines. We'll see what happens.















Thanks to everyone who followed the build thread!