de Havilland Aeronatical Technical School T.K. 4 from 1937

[Timo Starkloff]

I started cutting out fuselage parts. My brother actually isn't able to cut them out with his cnc. Works really fine since I discovered that the cheap plywood is easier to cut with a fine metal saw blade.

Edited By Timo Starkloff on 07/01/2016 19:38:49

[Timo Starkloff]

I switched to a second option to bring the parts on plywood by using an iron. It needs copied or laser printed paper, but works fast and accurate.

This weekend I received the winter 2015 magazine from Air-Britain with an article about the TK4. I found it by luck on a internet search. It contains many new and good pictures about the TK4 and a short but interesting text. Really great to get this document while building the model.

**LINK**

And after cutting out all parts I finally started the fuselage.

Edited By Timo Starkloff on 10/01/2016 18:58:46

[Timo Starkloff]

Fuselage part 2.

[Timo Starkloff]

A small but important step today, since both halves are glued together.

Edited By Timo Starkloff on 13/01/2016 18:22:59

[john stones 1 - Moderator]

That looks fantastic Timo, tricky formers to cut those, great job.

John

[Timo Starkloff]

Thanks, cutting worked quiet fine. I used to take birch plywood for most of my models until I switched to poplar in the last years. You have to design models and parts different since this kind of wood is very weak. But it is cheap and very easy to cut and sand.

I'm now preparing the fuselage with reinforcements for wing and elevator, adding an accumulator board and parts for the accumulator lid before covering with sheet balsa.

Timo

[Bob Cotsford]

That reminds me of the old KeilKraft Flying Scale models method of construction, fantastically light and rigid but lots of delicate half formers that snapped if you looked at them to hard.

Nice work Timo

[J D 8]

On those KK flying scale models I used to cover the former sheets with light weight tissue before cutting them out.

[Timo Starkloff]

Of course you have to be careful, but the half formers are not too thin. They have a width of 10mm and reinforcements at weak points like the cutouts for the stringers. Important is, not to damage the plywood by sawing, which is why I use a saw blade with very small teeth.

The fuselage looks better and better and improved a lot during the last two days. Good to have free time on a snowy weekend. I added a small cooling air channel in the lower front of the cowling. The accumulator sheet got a double bottom for easier installation of the Velcro tape. And I finally started covering the whole fuselage with soft 3mm balsa. Which is like painting a room - the preparation needs longer than the subject itself. I use a sponge to apply a bit of water to the outside of the balsa for easier bending.

For cutting out balsa parts, I pin the paper template onto the balsa and carefully cut along the paper with a sharp knife. Needs a calm hand, but works quick and fine. For 5mm balsa I need several cuts with little force to cut through completely.

Edited By Timo Starkloff on 17/01/2016 16:31:42

[Timo Starkloff]

[john stones 1 - Moderator]

My that's looking good, it'll take an hour to remove all the pins

John

[Henri Squier]

Congratulation, your very neat wood job is a pleasure to watch.

[Timo Starkloff]

I had only little time this week so progress slowed down a bit. Kind of a big puzzle...

The fuselage fits fine to the wing. The fuselage reinforcements for the wing are installed in the same angle as the wing dihedral. Simple thing which prevents excessively sanding.

[Timo Starkloff]

For the fuselage parts which are curved in two directions, I use thin balsa stripes.

And I started preparations for the canopy. I will make a template from foam and glass fibre for vacuum forming.

[McG 6969]

Hi Timo,

Great craftsmanship & an even greater pleasure to watch.

Cheers

Chris

Brussels, Belgium

[Timo Starkloff]

Thanks everyone. I also enjoy following building threads and so you have to give something back. It's good to see there are many experienced builder with many good ideas who still build and sometimes construct their own models. And of course, a forum thread is kind of a self-motivation during times when building is exhausting.

Regards, Timo

[Timo Starkloff]

I added the "keystone" and finished covering the fuselage with balsa.

[Timo Starkloff]

After drying over lunchtime, I sanded the whole fuselage and started work on the tail. First I marked the position for elevator and then glued the vertical tail in place.

[Timo Starkloff]

What I like about building wooden planes, is that it looks better and better the longer you build. Now it starts looking like a racer

Edited By Timo Starkloff on 24/01/2016 16:05:16

[MartinBell]

Looks great! Fantastic build.

[Timo Starkloff]

Thanks! From now on, there is only little progress visible. Now come all the small tasks to finish the wood work on the plane...

For the screws I always add a sheet of 0.8mm plywood on each side of the wing. It means more strength for the wing and secures that the screw breaks at this sharp point to give the wing free in case of an accident.

I also added the wires for the tail servos through the small holes, which meant more work than planned. I have to change that for the drawings and put the cable tubes a bit higher.

[john stones 1 - Moderator]

Yes it's looking like a racer, very nice work

John

[Timo Starkloff]

Working further on the tail fairing.

[Timo Starkloff]

I added fairings for the elevator from two sheets of soft 5mm balsa. After that I added tape around the fairing. This shall prevent damaging the fuselage while sanding the fairing.

[Timo Starkloff]

And I bent a 2mm wire for the tail wheel. The wire is glued to the rudder the same way as I do the aileron control for small aircombat models. The small brass tube will be later glued to the fuselage.

The TK4 had a fixed tailskid. But for a small rc model, this would mean problems for turning on the airfield, especially in windy conditions.

Edited By Timo Starkloff on 06/02/2016 19:16:30