1/18 scale Jukka Tervamäki JT-9T autogyro scratchbuild

After the scale model was masked & sprayed with primary colors as described above, the same methodology followed for the canopy, scratchbuilt by transparent plastic on a vacuum former. After the acrylic paint and mat enamel coat dried, I removed the masking tape and I saw the following:

The masking tape that I had used, had left noticeable marks on the transparent part of the canopy - something that had never done before! Being sure now that this scale model is indeed cursed, I dropped by the local grocery store around the corner from where I returned with few garlic cloves. Not having a similar experience before and fearing that if I try to clean the masking tape glue marks using White Spirit will make the things worse with a huge dull hood, I tried to rub the clear plastic part with alcohol which although more friendly to transparent plastics, had to pass crash test first. Dipping a cotton swab in alcohol and water solution and vigorously rubbing the hood, the masking tape glue marks, finally removed as if it was gum.

With my heart beating on normal levels again and using airbrush, light tones of basic colours and shades of sand sprayed at low pressure to represent the weathering and dusting on LG and the lower part of airframe. After a satisfactory weathering result, the scale model was sprayed with mat enamel coat. I left it 24 hours to dry and the individual parts of the scale model were test assembled (no glue), so that the autogyro model start to look like a united construction and please the eye.

Having now left the last part of the assembly of the individual already dyed parts of the model, such as the rotor blades, the cockpit flight & engine controls, the cables, the seat belts and other necessary details, I begin to hope that perhaps this model might be ready in 2010.

Nice editing, but you should introduce yourself first right?
Just polite ..........
Thanks.............

sherman a écrit:

Nice editing, but you should introduce yourself first right?

Already done

Some update pictures after washing / weathering / colour fading. Control cables are already installed. Still remain to be added:

• The canopy,
  
• Both propellers,
  
• The radio device & GPS,
  
• The engine control levers,
  
• The windshield and windscreen wiper,

and also paint some details such as engine cables etc.Details on rotor blades and the engine. The rotor blades are made of sterene sheet softened in boiling water to strech 'n' turn in a way to look realistic. Soft sanding applyied on the blade's leading eadge to be shaped as it should be. The spinner cone was made of an old 1/48 scale fuel tank tip, found in sparebox.

The JT-9T model posing for the camera...

Final details were added. VHF radio with headphones in the cockpit, mobile phone, seat belt buckles, main rotor control bars, cables, etc. To break the monotony of red, a toolbox and a tow added into rear storage area. At last, transparent plastic card were placed to simulate the wind shield glasses and of course the canopy in the open position.

Close-ups of scratchbuild engine. Although initially I plan to represent a brand new bright and shiny engine I discovered that it would not fit the with a faded, dusty and weathered autogyro. That is why I preferred to add much wear, stains from oil and scorched medals at several points and some rust as example in the exhaust.

The controls in this two-seater model autogyro, as with any trainer aircraft, perform the same movements. Feel free to notice the rudder pedals and you will see that the front and the back seat, right pedal is pressed to full FOR, bringing the left full AFT. This has resulted in turning the nose wheel to the right and turning the rudder of the tail in such a way as to twist the autogyro to right as defined by the position of the rudder pedals. Also notice that the throttle lever of back seat is attached on a bar connecting to the front seat engine throttle so to move simultaneously. The engine's power transmission is made with a wire, launched by the front seat throttle lever and lead the assembly of the engine. Finally, the control sticks are fallen slightly forward, which of course means that the elevators are set in a similar position.

I’ve been asked about the available space where the rear passenger puts his feet on. From the pictures of the model have been published, and the art images (click HERE) found on the article’s first page, it appears that the rear seat is too close to the back of the front seat - and it is also clear from the bluebrints (click HERE) of the real autogyro that it’s not my own assumption or a model building mistake. In real autogyro, rear passenger's feet are not squeezed behind the front passenger seat back, but they are placed left & right of the front seat! To make it more understandable, here is a picture where:

• The green lines represent the front seat passenger and the position of his feet on the rudder pedals and
  
• The blue lines represent the rear seat passenger and the position of his feet on the rudder pedals.

Also notice that the position of controls (stick, rudder pedals and engine throttle) meet the relative position of the elevator and rudder fins, the nose wheel, etc. The front & rear seat rudder pedals perform exactly the same movements as linked to the same wire transmission. If you also check the rudder pedals position, you’ll notice right rudder pedals pressed front end, bringing the left rudder pedals full back. As an effect, the nose wheel turns to the right and rudder fin turns in a way to turn the autogyro to the right as defined by the position of the rudder pedals. In similar manner, both control sticks (which perform exactly the same movements as they are connected to the same bar drive) are positioned slightly forward. This has the effect of elevator fins rotation so as to oblige the autogyro in the descent, as defined by the position of the control sticks. In a similar position the main rotor head is placed as required. As it is known, the autogyros and the helicopters leans to the left or right, elevates nose up or descent nose down, by turning the main rotor blades disc and secondarily to aileron and elevator fins (if present) and turn to left or to right with the rudder fins (autogyros) or tail rotor (helicopters).

Click HERE to watch a video showing a tandem cockpit seating positions as described. Picture following too.

It’s been few months since the JT-9T project was complete. I found nice idea to place it on a display base, simulating an airfield area with concrete ground. The idea was to establish an idea of an abandoned small airfield, now used by general aviation pilots for their weekend excursions. From my local store, I bought a 20x30cm polished wooden picture frame.

I add some grams of plaster powder and few drops of water with a syringe into a soft rubber cup to make the right mixture. Materials like plaster, start as a dry powder that is mixed with water to form a paste which liberates heat and then hardens. Unlike mortar and cement, plaster remains quite soft after drying and this characteristic make plaster suitable for the job. Keep in mind that adding salt into wet plaster mixture, reduce the plaster's hardening time and adding vinegar into wet plaster mixture, extend the plaster's hardening time. When the first layer of thinned plaster applied on the picture frame, a glass were pushed against the plaster to form a flat basic strong cast. The basic idea, is to produce a totally flat cast and later add some detail or apply extra stuff where is needed.

I left it few hours to get harden in order to be sure that the cast wouldn't break when I would try to cut it into desired shape. Meanwhile, I took the soft rubber cup which I used to make the plaster mixture, squized it to break the last hardened plaster left inside, so it would be easier for me to clean it afterwards and prepare it for any future mix. That's the reason this soft rubber cup were used for.

As soon as the plaster cast got harden, cut into shape and the concrete plaques were lined with a scriber, I used my airbrush to paint it. After the polished wooden frame was covered with masking tape, three different acrylic paint layers were applied on the plaster surface. First, mat black colour covered the area and then a light grey applied with airbrush, spraying in almost zero degree angle, to let the darker areas between the concrete plaques remain naturally dark. The corner was paint with earth tones and as soon as the acrylic colours dried, I tried some drybrushing on selected spots using sand tones.

As for he grass & plants, I used three different ways:

• From my local hobby shop, I got different colours of static grass, empty them into a plastic box and make a mixture.

• Found into my garden perimeter, I collect few natural stuff, cut and placed into plastic box for such use.

• From my local super market, I got a small wicker broom. If you look closely, you’ll find some very interesting stuff for scale modeling use and dioramas building.

Water based white glue for wood, which becomes transparent when it dries, is just the right for the job. So, I opened a 500 grams canister bought for 2€ only, pick a small quantity, add just few drops of water with a syringe into a small metal container to make the right mixture and finally I applied on the desired areas to be filled with grass & plants, using a wet brush. Because the mixture is enriched with water based glue, it is easy to correct possible mistakes.

As soon as the result was OK, I sprayed over with Humbrol enamel mat coat, to seal the paint and grass, so far. I left it overnight and as soon as the enamel mat coat dried, I add very few light & dust effects with chalk dust. Feel free to check final pictures of the JT-9T autogyro placed on the display base.

Thank you for following this thread and I hope you enjoyed reading this article.

I tried black paper background (instead of white) & different light conditions and I was surprised on how the model looks like. From now on, black background and low level lighting only...

PS. A little sparrow bird is now present on tail fin

Salut je m'incline bien bas car le resultat est vraiment super