JohnBoren

This is a Nakajima K9M Kikka. Japan had over 20 of these on the assembly line before the war ended. One took flight and it flew only once. My model is a 1/6 scale, spanning 65.6 inches. Overall length is 59.7 inches. To keep the scale intake and exhaust sizes I decided to go with a pair of Freewing 70mm EDF Power System w/ 2957-2210kV In-runner Motors. A set of JP Hobby electric retracts will be used but I am still up in the air about the gear struts. The model will be constructed entirely out of wood. I hoping for a take-off weight between 10 and 12 pounds. The fuselage and engine nacelles are planked with 1/8" thick balsa. The wings were covered in 3/32” sheet balsa while the horizontal and vertical tail were covered in 1/16” balsa. To date it has taken almost one month to get to this point during the build. I had the fuselage designed first but the rest of the parts I designed once the fuselage was under construction.

The model is going together very well with only a few mistakes on my part that I have since corrected in my files. As seen with both engine nacelles installed the framed up model weighs in at 4 pounds even.

John Boren

JohnBoren

More Build Images

JohnBoren

More Build Images.


John Boren

Don Sims

Looking good John!

riverrat

Nice!!!

JohnBoren

I fiber glassed the engine nacelles last night. Because of their complex shape I tacked the 2 oz cloth down with 3M 77 contact spray that I applied very lightly. It worked great. I then covered the cloth with West Systems Epoxy. The two photos show the nacelles before and after the resin has been applied.


John B

Panther

WOW! what a project. I take it you have your own laser cutter and CNC skills. Makes this old fellow jealous. We could only dream of this stuff years ago.
A lovely model.

JohnBoren

Yes, I purchased my laser about a year and half ago. I've been building model for 50 years Been learning Auto Cad for about 20 years now. Still Lots of stuff I don't know how to do. The laser was the best tool I ever purchased.


John Boren

Panther

Thanks John.
It is only the CAD part that puts me off looking further into it. If I was younger I wouldn't hesitate. I'm nearly 73 and been building since primary school too. Always scratch drew plans and scratch built because in NZ there was very little available but balsa and aero cement back then. Things have sure changed.
Maybe I could gain enough knowledge to cut wing ribs or the basic stuff but that would be about it.
Just as a curiosity, what make/model cutter? Thanks

JohnBoren

Today I constructed the air intakes for my nacelles. I used 1/64" plywood. Before I glue them in place I will add a wrap or two of carbon fiber tow in a couple places along the duct to help prevent it from getting sucked inward.

quorneng

John
Just a thought and It might be difficult to construct but if the nacelle formers were extended so the inlet duct could be clued to them the duct would not only be well supported against collapsing but the nacelle itself would be considerably stiffer.

solentlife

I have to say also that my Laser has paid for itself many times ...... and there's no real need for CAD as I can draw in Paint ... save to JPG .... import to laser and vectorise ... cut.

I have to admire the build .... superb work.

JohnBoren

"@quorneng" I certainly could have designed the nacelles so the intake duct would rest against the inside of a couple formers but that would have required more work on my part and I'm lazy. This would be something to consider on the next one that gets built. I'm pretty sure the plywood ducts are strong enough as is but for almost no weight gain I can simply wrap a piece of Carbon fiber tow around the duct in one or maybe to locations and glue them in place with thin CA.

I really do appreciate your comments



John Boren

JohnBoren

Today I mounted the engine nacelles. They need to be flared into the front and rear of the wings. I also installed the landing gear to confirm she is sitting at the right angle. I need to machine a steel 1-1/4" long extension to the nose leg but for now I'm simply using a wood dowel.



John Boren

pmullen503

What software do you use to vectorise?

JohnBoren

She is on her wheels.


John Boren

Panther

Thumbs up on that John.

JohnBoren

A few more build images.