006: THE FALKE ENGINE - Piscean Works

MAKING THE FALKE ENGINE

The original concept was for the Falke to be placed in a repair bay diorama and with the Pilot/s testing its modified engine. However, as the project progressed, I decided that it was best to be made into a stand-alone model. I have seen online that most of the Ma.K completed models can stand on its own with just a base. Dioramas are really optional and so, I can also revisit the diorama idea later when time permits.

The insides of the Falke is hollow and so, has a lot of space for me to work on. This means I do not have to design a new compact circuit board nor re-program an existing ones, although the idea was quite tempting. I wanted to complete this model as fast as possible, since I can only spare about an hour per day for this. Moreover, I did not bring my any of my microcontrollers and programming tools with me. To save time, I would be looking for off-the-shelf solutions instead of customisation. Another plus is that, should the circuit be spoilt, I can just buy another electronic kit/module and replace it.

The original idea was just to light up the engines and backlit the instrument cluster that has been re-cast in clear resin for me. As I explored the model part by part, I realized that with some modifications, it is possible to light up most of the parts that got me interested. So, as the project progresses, a LED turbine, some spotlights, a lighted Pilot visor and other lighting features were included.

THE ENGINE NOZZLE: REMOVING THE CHROME

It was a great surprise a years ago, when I first realized that the Falke’s engine was actually made from a Vitagen bottle. This sent me on a wild goose chase to look for that very exact bottle but then I realised Malaysia’s Yakult bottle did not look like that. Only the Vitagen bottle does but it’s a lot bigger. Therefore, I would not know if the Hasegawa Falke was the same size as Kow Yokoyama’s original unless I have a Revell 1/32 P-38 Lightning to compare instead.

From Left to Right: Malaysia’s Vitagen bottle, Hasegawa Engine and Malaysia’s Yakult bottle. If you noticed in the background, there is an oval shaped pencil sharpener which could have been the Third-Eye’s dome but it’s the placement of the holes which did not appeal to me. But here’s a thought: If the Malaysian Vitagen bottle was the exact size, then the Falke would be very much bigger!

The engine nozzle part was beautifully molded with a lot of details but for my lighting purposes, I needed them to be hollow. So, I am not going to use this but to find a replacement. I could have cut strips of styrene to recreate something similar to this design but the styrene plate I had was either too thick or had gone brittle through age.

An alternative solution was to find replacement part which has almost the same diameter as the engine nozzle. And after scouting about at the local stores, I found an almost perfect match, which were actually parts from a plastic water filter.

There are a lot of potential parts here but not all would be suitable for the Falke. The highlighted ones are the parts that I am going to use.

Only the middle cylinder, the outer chrome part and the hexagon plate would be used for the engine nozzle replacement.

LEFT
Removing the chrome took me a lot of time (weeks!!!) due to trial and error. This was not a normal type of model-kit-chrome but industrial chrome!

RIGHT
At first, I tried using Dettol with and without water but it did not work. Then Clorox did the trick but it produced a lot of gas and I had to release it by opening the rusting cap once in a while. I was worried the glass bottle exploding.

I rinsed the part with water to stop the reaction process with the Clorox. After brushing it a few times with a scouring brush, the part looked lovely with some leftover chrome and half-eaten areas. This will make a nice worn engine nozzle!

I wanted to continue with the process to finish off the remaining stubborn chrome but there is also a worry that the plastic could become brittle or worse.

THE ENGINE NOZZLE: CREATING THE LED ENGINE

With that part prepared , the next stage would be to get some LEDs that can fit into the inner cylinder. And to keep in line with the idea of using off-the-shelf solutions, I got some 5mm yellow flickering candle LEDs. The best part is, when you bunch them up together, minor voltage variances would make each of them flicker differently, almost as if they are random. Because I am still undecided if the Falke is to be flying with full power, these flickering candles makes the engine look as if they’re being tested or warming up.

This is the flickering candle LED which is available only in 5mm yellow with clear lens. It has an integrated circuit (IC) built inside to control the ‘flicker’ effect of the LED and is almost random. Almost. Because if you observe it carefully, after a few seconds, the flickering pattern repeats itself.

These LEDs are used as electronic candle replacements. The earliest version used actual yellow LEDs soldered to a small circuit board which has the IC on it. If you find those and replace the current limiting resistors, and a warm-white LED, the effect would look much more realistic.

To fit into the cylinder, the six LEDs will be formed within the walls of the filter piece.

The six flicker LEDs has their Negative leads (short ones) bent as shown on the left. This is where all six of them will be joined. The negative legs need to be tinned before they are all soldered together.

LEFT
Arrange the six LEDs with the bent leads (Negative) facing the centre, touching the other five leads. You might want to use a double-sided tape as soldering jig to keep them in position while you solder.

RIGHT
Cut off the long lead (Positive) about 5mm from the LED itself. Coat it with rosin flux and then apply solder. Do the same with the 100 Ohm current limiting resistors too. And finally, solder each tinned resistor onto the LEDs.

LEFT
In the end, this is how the 6 LEDs would look like. You can solder the resistors before joining all the inner leads to form the shape but the long leads of the resistors would hamper your soldering later on.

RIGHT
The finished Engine….
There were some complications on the rear of the water filter and so I removed the plastic part. It was easier than re-soldering the LEDs.

Quick test with the power bank, which gives out 5 volts.

By now you would have noticed that generally all of my circuits are operating at the 4.5v (3x AAA batteries) or 5v (USB power but do not plug form a PC, please). The reasoning was that during a model competition or display, when the battery runs out, it is easier to get those AA or AAA batteries or even recharge the mobile phone power bank. If you design the circuit to run off a 12v system, it would require 8 AAA batteries or well, you can get a 12v wet cell from a 7-11 store…

The flickering effect of the Falke Engine. There are 6x Yellow Candle LEDs inside.

THE ENGINE NOZZLE: LED ENGINE SOLDERING

This section is a recap of the soldering that I did in the previous article. I needed to fit six 5mm LEDs inside the water filter’s inner wall. The 5mm LEDs will fit just fine but I needed to make sure they are properly aligned in there. This is why their Negative leads were bent; to form a framework for holding all the six LEDs together. You will need to test the bending dimensions as I forgot to take exact measurement of the bends but the prongs of the long-nose pliers helped.

IN SUMMARY

Preparing the LEDs

How to bend the Negative lead

Using the long-nose pliers, I shaped the bent like so. The width is about 4mm or so.

Preparing the Resistors

Soldering the Resistors

Heat-shrinking and lead-off

And so, there you have it. This is a very simple way for me to solder all six flickering candle LEDs to form the core of the engine without having to resort to using any circuit boards. Another advantage of using these LEDs is that, when connected to a transistor, their flickering effect could be used to drive other differently coloured LEDs for flickering.

In the next article, I am going to show you how I painted the engine with some weird painting effects (to me, that is) making the engine look well used.

THE ENGINE NOZZLE: PAINTING THE ENGINE

Once the LEDs are done, it’s time to complete the engine nozzle. This section deals with the inner engine and its outer cover sleeve. It was tempting to put in a 1 watt LED to complement the six 5mm flickering candle LEDs but this would mean needing to create additional PWM circuit to control it. On the other hand, using a normal huge 5watt resistor to drive the 1watt LED will be disastrous as both resistor and LED heatsink can melt plastics in under a minute.

After the coat of Mr. Surfacer 1000 primer has dried, I gave it a coat of Mr. Color GX2 Ueno Black to set the stage for Mr. Color’s #159 Super Silver. This would make the square hole details on the ring look very metallic. The black streaks were thinly sprayed inside the engine’s exhaust. Note at this stage, the lights from the LED are still very bright.

Do not spray the primer and paints too thick inside the exhaust. The original hexagon round plate did not leave much gap. Extra paints will thicken the side walls and the plate will easily scratch these paints off. For the outer ring, Mr. Colour Gx103 GX Deep Clear Blue was sprayed.

LEFT, RIGHT
I darkened the blue again and used Tamiya Panel Liner Brown to darken areas in the hexagon plate and exhaust area, hiding the scratched areas. I used air from the airbrush to speed up the drying process of the Tamiya Panel Liners as this to me, leaves more paints while evaporating.

MIDDLE
Lastly, I aligned the six LEDs with the hexagon plate so that their hotspots were covered by at least three of the hexagon’s filled cell plates. If you looked at the engine directly, you will not be blinded much. Any excess LED light is now absorbed by the dark paints.

For the engine’s outer cover, I primed it with Mr. Surfacer 1000 and while it is almost dry, I used a brush with thinned primer and began to stipple the surface to create some rust texture. As for the stubborn industrial chrome, I put some thinner on a cotton bud and wiped the primer off.

I sprayed a layer of thinned Mr. Colour #61 Burn Iron followed with random spots of Mr. Colour #10 Copper and also Mr. Clear Color GX103 GX Deep Clear Blue.

The inner edges of the ‘rings’ on the outer wall were masked off and sprayed with a dark matte mixture of Gaia Notes #002 Pure Black and #006 Flat Base. The excess paints were used again to streak the inner walls of the engine cover and random burnt patterns. A very thin layer of GX103 Deep Clear Blue was sprayed at the rims.

The outer five ridges were masked and given the same dark matte treatment similar to the inner edge but with a bit more blue at the other edge. I used two airbrushes simultaneously so I can save time without having to clean it for each colour. In this light, you can see the dark streaks in the inner walls of the engine cover. This is the final result. Unfortunately, the blue is unconvincing and should have been ‘rusted’ instead.

THE ENGINE NOZZLE: MOUNTING TO THE FUSELAGE

With the engine nozzle done, it’s now a simple matter of joining the engine’s halves and placing it to the Falke’s main fuselage. But do not glue the completed engine to the Falke’s Fuselage just yet. The engine needs to be pushed out by a few millimeters to take in the microUSB adaptor which is to be mounted later on.

To mount the completed LED engine to the Falke, you will need to make some holes in the ‘Yakult’ bottle halves C#1 and C#2. The first hole on the left is big enough to allow the LED’s leads to fit into the plastic comfortably. The second and third on the right is to allow the wires to pass through and enter into the main Falke Fuselage. You might want to make a knot inside the fuselage later because if it falls out, it would be very frustrating to re-thread the wires back in as the two halves of the engine has already been cemented.

I made an Aves donut/cushion to make sure the two parts mate together well. If you look closely, it night show and if you asked me, I would say it’s a flexible bellow as this part is directional…. Lastly, using some spare styrene sheets, I made some panel covers too.

Once the two halves have been glued and primed, I gave it a dark coat of Tire Black and a layer of matt coat. Then proceeded to weather it with nothing more than just Tamiya Panel Liner Brown and Black.

Initially, I used Abteilung 502’s ABT160 Engine Grease for the lower part of the engine but removed that later as it took too long to dry and it mysteriously has my fingerprints although I barely touched it.

ADDING DETAILS TO THE ENGINE

At this point, I am preparing to mount the Engine into the Falke’s fuselage. Once the two fuselage halves has been closed, it would be too late to work on it. So, now is the best time to add some details and weathering.

I drilled some holes into the engine where I would be placing some copper wires to make the engine look more ‘busy’. These 0.5mm copper wires were stripped from a 3mm electrical cable. I am not using Superglue on this but white glue. Plus, I am bending the wires into shape and hope they will hold.

As for the other ‘pipe’ holder, I cut off a segment from a three-pipe straw which I got from a meal during my MAS flight. After bending the wires, I got it to fit. But it looked fragile and especially for long stretches, the copper wire will definitely bend. Then again, this is acceptable since nothing in this Falke is brand new!

I cut off one of the sprue’s numbered tab, shaved off the number and drilled three 0.5 holes. I thickened the part with some plastic styrene and sanded it level. For details, I glued another strip onto the front.

With the new detail in, the piping now looked the part. And for the right copper ‘pipe’, I gave it some turns and was hoping to make a plastic detail but I forgot…

The engine was then given some more Panel Line Black and Dark Brown as washes and streaks, followed by a slightly more matte topcoat and some Abteilung 502’s 165 Faded White. Panel Line Blacks were slowly blown dry by the airbrush to create that ‘leaking oil while in flight’ look.

With the Falke Engine done, the next step is to modify it so that I have a nice gap to insert the microUSB connector.
(Update: The microUSB was a very bad idea unless it has through-hole legs…)

PREPARING FOR USB POWER

The Falke’s original engine sits on the fuselage with its exhaust pointing at a downward angle. It is not horizontal as assumed. What I am going to do next will compromise this setup. I have looked all over the Falke for a suitable place to mount the microUSB-to-DIL adaptor and the only place would be the small gap between the fuselage and the engine. This gap of 3~4mm is quite wide in terms of scale modeling. Before you attempt to do this, you need to read the manual again as there are some parts which will be affected by the slight relocation.

Please do remember that although this Project uses USB connectors, it does not mean you can plug the Falke to your PC or other computers. The mobile power bank can give you up to 2.1A of current whereas the PCs could not. In the worst-case scenario, it might damage your PC!!!

So, without further ado, I am going to push the engine out…

There will be quite a bit of work to extend the engine and it is not a simple case of just trimming away some alignment plastics

Using a 3mm drill bit, and the adaptor as the template, I made the necessary pair of mounting holes for the M3 nuts and bolts. I then soldered a red cable (Positive) to the hole named VBUS and a black cable (Negative) to the hole marked as GROUND. Once the nuts and bolts has been secured, I locked the threads with Loctite. At this point, I am not too worried about the screws scratching and shorting the data lines since there are no data nor voltage passing through the connector and (I hope) the same goes for the Power Bank.

This the engine’s new position on the fuselage. The USB adaptor has pushed the engine out by quite a bit. So, you will need to trim the plastic millimeter by millimeter until the front cylinder edge of the ‘Yakult Engine’ does not touch the USB adaptor anymore.

This is as far as I can cut but you need to test-fit again and again.

In the end, the USB plug is able to sit comfortably but the ‘Y’ shaped part D18 will need to be relocated among many other parts. There are some other parts (highlighted by the yellow area) which I will not be using since they can complicate matters when the USB connector is plugged in or removed.

Reinforce your microUSB Adaptor!

The reason why I extended the Engine is so that I can attach the USB connector to the model and I can remove it when I wish. The idea was great but when I applied it, because of the connector being a SMD version, it does not have any mechanical strength when the USB was cable accidentally pulled. So, just read it and maybe, don’t use this method.

Here is a picture if a broken microUSB adaptor. It was so easy to tear it from the circuit board due to the weak soldering. And once it is torn, most of the time, it is very time-consuming to recover from it. As you can see, there is nothing to stop the USB connector from coming off with normal force.

By placing the adaptor underneath or even mounting it to a model, it would be facing a lot of potential stress when the USB cable is connected to it. From plugging to pulling the plug, to accidental drops or even knocks, the connector can be torn off.

Look at the picture again. The yellow circles are the solder pads for the microUSB connector while the yellow arrows are the metal tabs (I call them ‘wings’) which was torn off. Because of the way the soldering was done at the factory, you need to re-melt the solder or even add a little more at the ‘wings’ to give it more strength.

One more thing, when you need to use these adaptors, do try to get as much as you can because (at the time of writing) there are more than two designs and each had different dimension, plus their screw locator holes are different as well.

Update: There is another design where the USB female connector has through-hole leads and well, if you can solder them to the other side of the circuit board, they might hold much better. For me, I just bypass this failed attempt, solder a USB wire directly and call it a day.

So, am I ready to close the Falke? Nope. Not by a long way. In the following chapter, I will show you how I created the Falke’s Turbine intake without using an actual fan…