1/18 scale Tervamaki Engineering JT-9T autogyro

[Nick_Karatzides]

CHAPTER IX - Applying paint, wash & weather effects

Model parts were washed with liquid soap and warm water to disappear leaving oil traces, fingertips etc and then sprayed with light grey primer.

The first base color layer sprayed with no problem and then a second white color layer applied on specific spots to simulate enlightened areas. Then, using very diluted acrylic color Vallejo paint, 2-3 extra thin layers were sprayed throughout, until the result become realistic and simulate correctly the enlightened areas.

 

[jspitza]

To prime or not to prime? That is the question I pose to you tonight, Nick "The Great one" Thanks again for inspiring me to go beyond "the Kit" Take care, Jeff

 

[Nick_Karatzides]

As soon as the previous layers of acrylic Vallejo paint and gloss coat varnish dried, I placed small slips of paper between the frame and the sheet of the fuselage, to protect the red colour that was already applied and dried. Next, I masked areas not to be painted using the adhesive Tamiya tape and sprayed with the interior green colour.

 

[Nick_Karatzides]

After the interior colour dried, the slips of paper and adhesive masking tape removed and minor corrections were made in 1-2 spots with a fine brush. The result was sprayed with gloss varnish, to apply washing on certain points.

 

[Fenlander]

It is not easy for a very novice modeller to come up with sensible comments about work like this. It is truly stunning. I would have no idea how to have made the basic airframe never mind that amazing engine!!!!!

You could have made this into a book. Thank you for sharing your skills and techniques.

 

[Dograt]

Like wise

 

[Dograt]

Just the Job ! Looks fantastic, I take its the walkie talkie is to call for extra refreshments when you need them !!

That is one hell of a setup

Is that watercolor crayons or oils ? then mixed with turps/water and then some KLear?

 

[Dograt]

Sorry I have the answer now I seem to have missed a few posts somewhere I can see it now washing up liquid and chalk

 

[Nick_Karatzides]

The steps are slow, but I prefer steady progress rather than hastily. Unfortunately, the problems are not missed. Although I do not think myself as awkward, after the incident with the (voluntarily flying) autogyro model scaffolding under my sleeve and threw (launched to be precise) on its own initiative, brought about 4 or 5 spin turns and finally abnormal landed about 5 feet away and 3 feet lower, I begin to believe that this model has been seriously voodoo curses. Despite the delicate structure of the fuselage, the use of CA glue and maybe a mirracle, were the main reasons that the model escaped having suffered only a broken landing gear, scratchbuilt again.

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 very soon.

 

[Nick_Karatzides]

Some update pictures after washing / weathering / color 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.

 

[Fenlander]

Glad to see this wonderful project moving on gain, looking stunning.

 

[Nick_Karatzides]

Details on the rotor blades and the engine. The rotor blades are made of sterene sheet softened in boiling water to stretch 'n' turn in a way to look realistic. Soft sanding applied on the blade's leading edge to be shaped as it should be. The spinner cone was made of an old 1/48 scale fuel tank tip, found in sparebox.

My little JT-9T princess is posing for the camera...

 

[jspitza]

Hi Nick!

Great to see your posts again. What a gift you have especially when it comes to turning plastic into metal! Take care, Jeff.

 

[Backbreaker]

Totally Awesome.

BB

 

[Nick_Karatzides]

CHAPTER X - Epilogue

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 rudder pedal is pressed to full FWD possition, bringing the left ruder pedal in full AFT possition . 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. 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).

 

[Backbreaker]

:respect:Simply STUNNING !

BB.

 

[Nick_Karatzides]

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 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 blueprints 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, have a look in following pictures, showing a tandem cockpit seating positions as described:

• 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.
  

 

[Nick_Karatzides]

CHAPTER XI - Tarmac & grass display base construction

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.

 

[Nick_Karatzides]

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

• 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.
  

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

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

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.

 

[Nick_Karatzides]

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.