de Havilland 60 III Moth Major SX-AAA - peanut

[g_kandylakis]

So, another build thread that got lost, a rather recent one and not so long, which makes it possible for me to repost it.

Perhaps not in full detail (no real need to again post the failures as well, is there?), but it will give the idea.

So we start with a bit of history.

For a variety of reasons, aviation in Greece was considered for many years, mainly a military issue. Even though the first flights in Greece were made by civilians who trained and bought airplanes on their own expenses, it took until the early 30s for commercial and private aviation to appear properly.

The first private plane was a d.H. 60 Moth Major, licenced as SX-AAA (SX = Greece).

The plane configuration and the colour scheme made for an interesting peanut, with the exception of the rather small wing area, so it would have to be a light peanut. Quite a task since I hadn't built a peanut for over 10 years.

Before starting, it was a fairly easy subject to gather documentation, especially if one has Lars Tolkstam helping out. He provided most, if not all, including the original sales brochure, with a very atractive side view in the colors of the greek one.

The model was started over a year ago, with the rudder as the first item.

Time passed until this summer when the project was revived, with the goal to finish it in time for the 2025 IIFI even in Nijmegen.

I started with the wings

[g_kandylakis]

Parallel, work was begun on the fuselage, as making 4 wings one after the other can become quite boring.

Standard construction, mostly 1,2mm balsa.

Bottom longeron fronts split in half and laminated on a form to take the large curve, for zero strain on the structure afterwards

[g_kandylakis]

fuselage sides done, wings done, time for a first test assembly as soon as the fuselage box was a thing

[g_kandylakis]

I wanted to have a good appearance, even if it meant extra weight, so I went with balsa planking for the front and rear tops of the fuselage.

Formers were drawn up with stringer slots, to ensure proper support for the thin balsa that would follow.

Some pre-forming. held in place with Tamiya tape (most useful) and then careful and slow glueing of the planking to the structure

Regarding the formers, I do all the transfer of drawings to balsa (regardless if made by me or others) with 3M spray mount glue. Once everything is cut and sanded it is very easy to remove the paper template and the glue goes away with it, leaving a clean balsa part.

[g_kandylakis]

with the rear part glued and trimmed, next came the middle and front ones. Same thing...

Weight check, 0,9 grams for the fuselage so far.

[g_kandylakis]

I have to say ("bless your own house else the roof will fall over your head") that the uploading of images through drag & drop is by far easier and faster than with the original HPA...

Back to the model. Nose section almost complete with a thin ply as a "firewall". My experience with balsa is that it rather quickly wears out, so I wanted something more durable.

Assembly check again... The amount of time waisted doing these assemblies cannot be measured, they sure did help with motivation though.

[g_kandylakis]

Main landing gear. Took some thinking to arrive at the design of the wire structure.

Everthing was to be covered with balsa, to simulate the tubing and fairings later.

[g_kandylakis]

new weight check, all structure except horizontal tail, 2,3 grams.

Fairings added, wheels turned out of balsa ply, nose block also sanded to shape, with a back plate of plywood, exactly as the fuselage front.

[g_kandylakis]

Being a biplane, I wanted to ensure a strong and stable structure, properly aligned.

The cabane struts play a very important role in this, so they would be made of 0,5mm wire ends, inserted into basswood bodies.

To ensure accurace and symmetry on both sides a simple jig was made for the assembly of each side.

Once the ends were in their proper positions, they were CAed to the basswood. One side first, than the other.

[g_kandylakis]

and some more assembly shots

[g_kandylakis]

a critical decision was to cover the cowl area with thin polystyrene sheet.

Already aknowledged many times, it was Mike (ZK-AUD) from New Zealand whose posts convinced me to use this heavy but nice and smoothly finished material for areas originally in metal.

The extra weight on the nose would not harm and the finish would be much better, compared to balsa or paper.

Again, to reduce strains, the panels would be glued after pre-forming. Vacuum forming, my usual way, was not necessary for this model.
The simple curves were made with a heat gun softening the material just enough on the form.

[g_kandylakis]

Only the nose part needed plunge molding, and the plastic was glued to the form afterwards.

The form, the actual nose, got some hollowing out to make space for any needed nose weight later on.

[g_kandylakis]

Cutouts were made, not yet to final contours.

Again an assembly, this time with tissue covered parts.

There is a rumour that I initially covered the model in condenser paper and failed terribly during painting with acrylic paints.

There were even some AI created images of the model covered in condenser paper.

I deny everything, it never happened. Already blocked from my memory...

Anyway, working with esaki tissue proved a much better choice in man respects, except weight. But the end result was way better that what I would have achieved with condenser paper.

[g_kandylakis]

wings covered and drying during shrinking.

A bit of washout, about 0,8mm set under the wingtip trailing edge

[g_kandylakis]

Fuselage. struts, landing gear etc painted azure blue acrylic, wings and tail surfaces silver lacquer, wing registration letters black.

Everything airbrush sprayed, following two coats of 50/50 thinned nitrate dope.