1/4 scale Ka-3

[Fred]

Hi there,

First of all, thanks to Alan for the 3 views !

So, after my 1/5.5 Grunau Baby, it's time for a new scale ship !
This time, the Ka3, 2.5mtrs wing span.
Let's glue some wood !

As usual now for me, I've started with the "front box" made with 3mm plywood (from the local DIY store...)

[Fred]

Then, it's time for hard wood strips to simulate the tubing construction of the real one.

I've used 10x3mm strps, but if I have to do it again, i'd rather use 2x  3x5mm strips. Much more easier to bend ! :rolleyes:







Nothing really difficult here. The hardest part of the building was for the rear part of the fuselage...Finally, no real difficulties, but you must be precise here !

[Fred]

Then, it's time to build the wings !

Really easy here ! Ribs are all the same (ok, ok, almost !), the wing is flat, rectangular... A real beginner wing here !





The first 4 ribs are in 3mm plywood. The wing spare come from the DIY shop and the key wing is in 8mm carbon rod.

[Fred]

Ok, so, we have a set of wings and a fuselage... time to put everything together for the first time :





Contemplation !

Fred --> happy !  :p

[Fred]

So, it's time to start the "webbing" on the fuselage. First, I was thinking to cover the entire fuselage with balsa, and simulate the tubing with the 10x3mm strips... Finally, Why not reproduce the real structure ?! Less hassle ! And very light and strong ! (Ok, the weight is not an issue here in Ireland !  :rolleyes: )

[Fred]

Now, a bit of paint for the cockpit interior...

Ok, Grey like the Irish Sky !  :p  Camouflage !

[Fred]

A bit of work on the wings now.
Put the TE made with 1.5mm liteply.

Note the wing root. Scale now (design error here...Ooopss)

[Fred]

Now, the ailerons :

Really easy.. nothing to be explained here... photos talk for themselves !

[Fred]

And finally :


So, missing on the picture : the wings root and the sheeting.

Now, it's time to start the V tail !  Yep, I keep the best part for the end !


Fred

[Fred]

Ok, let's make the wings tips.
One of the Ka3 Particularity is to have a hollow wing tip (mean that the wing sheeting is not going to the tips)
So, the last 2 ribs are made with 3mm balsa and the wing tip, by using 1.5mm liteply.
Here are the pictures before gluing :








So, this week end, the plan is to finnish the wings (sheeting) and to start the V Tail !

See you next week,

Fred

[joe]

looks excellent Fred.the Ka3 is a very nice looking sailplane.the v tail looks unusual on a vintage scale gliders.very cool though.
can't wait to see it with a suit of clothes on  

[Fred]

Hey Joe !
Thanks a Mill !

Hopefully, the V-Tail will be finish to be designed this Week End... So, finger crossed.. If everything is going smoothly, the glider will be ready to cover next week...

I'm on a hurry, should be finish for retroplane !!

Finger crossed !

Fred

[Alan_Perse]

Looks great Fred   . Will you be giving it spoilers like the full size.
Hope to see you guys up at Killakee in the next few weeks, hopefully, haven't flown in months.

[Fred]

Thanks Alan,
Yes, he will equiped with spoilers like the real one. Scale I said !  

What are your plans for Sunday ?
If the weather is looking good, I've plan to meet Joe at Mount leinster...
If interrested, I have space...
086 083 1782, send me a text !

Fred

[Fred]

So, let's continue with the elevator :

The elevator is made like a wing. The profil is a NACA 00008. No spars but 2 wing joiners made with carbon tubes.

first, cut all the ribs (not a lot   ) :



And glue them on a "false" TE, made with 4x4mm balsa strip :



Then, this is the critical phase of gluing the carbon tubes. Critical because you can input some wash-out during the process.... But slowly but surely, take your time and all will be fine...



Then, you can glue the TE to the ribs :