Ardpol 1/72nd Aeromarine 39B (Floatplane) By Eric Gallaud

History

In 1917, the US Navy placed an order with the Aeromarine Plane and Motor Company for 50 of the model 39A and 150 model 39B trainers. At the time, this was the largest single order for US Navy aircrafts. On October 26, 1922, a model 39B piloted by Lt. Cdr. Geoffrey De Chavalier, made the first landing on the deck of the Navy's aircraft carrier, the USS Langley. The plane described here is a 39B floatplane.

Characteristics

• Engine : Curtiss OXX-6 100 hp
• Wing span : 14,32 m
• Length : 8,12 m
• Weight empty : 880 Kg
• Weight loaded : 1137 Kg
• Speed : 120 km/h at the sea level
• Service ceiling : 1500 m
• Range : 440 km

Fuselage assembly

As usual, I begin with the interior of the fuselage, with the seats. As they are photoetched, I bend them with my bending tool provided by Daniel Munoz, then some CA glue superfluid, et voilà, it is done.

After that, painting the inside. According to the notice, it was "Interior green", which is unusual for this period. So, I use the HU78 cockpit green as basis colour, airbrushed.


Then, I apply a wash (HU98 chocolate + a drop of HU33 black diluted with white spirit) in all of the recess and hollow.

And then a dry-brush with the basis colour highly lightened with HU103 cream. Details painting.

The seats are painted as all of the inside of the fuselage. The harness are painted in HU121 pale stone and their details in Tamiya XF56 metallic grey.

After that, I scratchbuilt the control columns, because, in the kit box there was only one, broken. I build them with brass wire, with a little piece of masking tape, secured with CA glue, for the handle.

The floor is painted the same way than described above, with the petrol tank in Tamiya XF16 aluminium, the rudder bars and the control columns in Tamiya X18 semi-gloss black and the handle in HU62 leather.
The floor is glued in the starboard side of the fuselage, seats added. At this moment, I had a problem, the front seat was too high. I removed partially the tank straps, on the top, after that . everything went well. Then I added the instrument panels, painted in Tamiya X18 semi-gloss black, with the bottom of the counters in transparent film, painted in white.
The fuselage is now closed. I start to tight the 2 half in place with 3 clamps, then I put some CA glue superfluid in between directly with the tube or with a sewing pin. I use also this glue to fill some little holes, gap. It works very well if you sand the glue very quickly after drying (less than 1 minute after glue application). It is better to do this operation with small length.

Wings addition

Now that the fuselage is closed, I can drill all of the holes required for the rigging (0.3mm) and glue the elevator and the rudder. The last one is reinforced with a piece of spring steel wire 0.3mm diameter.

The lower wings are to be glued to the fuselage, reinforced with some Evergreen rod of 1mm. Next time, I will avoid to do that, it is not strong enough, don't ask me how I know that. The wings are at first fitted with the right dihedral angle, 2°, with 2 wedges of 2mm height placed at 60mm from the fixation of the wings. Then, a small drop of CA glue superfluid put with a sewing pin, et voilà !! Note that I drilled all of the rigging holes prior to glue the wings.

The top wings are glued the same way with the same dihedral angle. The holes required for the rigging are also drilled.

The cabane struts are adjusted and reinforced with some spring steel wire 0.3mm diameter.

Wings and fuselage painting

Now, I can paint the exterior. I chose the "Battleship grey" from Misterkit (acrylic paint). It is thinned with methylated spirits (about 50/50).

After masking, I spray some matt black (HU33 thinned at 50% with Humbrol thinner) around the cockpit openings.

I put the decals in place. Those of the rudder are not very easy to install and require some paint corrections (Tamiya X3 "royal blue" and Tamiya X7 "Red"). At last, I add the 2 large markings "560" and, to avoid any silvering under the transparent film, I spray a coat of satin varnish (Prince August Air) within the following hour.

With a Q-tip, I put some grey pastel chalk slightly darker than the wing and fuselage colour. I put it between each wing ribs, from the leading to the trailing edge. I repeat that application until I reach the required result.

An underside view of the plane. I added the struts which support the elevator.

Floats

Next step : the floats. The two parts assembly of the main float requires some adjustments and, after gluing, some filling/sanding. There are also some bubbles to fill.

The main float fits well onto the beaching trolley.

The floats are painted in HU118 (Matt US tan).

Some nervure are drawn with a watercolour pencil which allow to shade off the lines which are too visible, it is also possible to remove them completely with some water.

A coat of Tamiya X26 ("Clear orange") is them airbrushed. The nervures were not enough visible, it is difficult to see them now.

The various covers are painted in satin black as will be the struts between the floats and the fuselage or the wings, without anymore information.

The interplane struts

I started to reduce the thickness of one stick with my sander (from 2 to 1mm).

Then, I cut the stick into several bits, slightly longer than required. After that, I split each one of these bits, in two.

I cut and sand each bit to obtain the required shape. I made a lot more of eight struts. Almost the double, due to the process risks.

A very delicate step : I drill the two sides of each strut with a 0.5mm drill. Hopefully, I prepared more struts than required. Each one is glued onto a brass rod which will be used as a base for the following steps, then will be cut at the right length for the assembly.

I use a wood staining bought in a diy store. The stain chosen is light, I can always darkened it with several coats.

Then, the varnish. I use the Tamiya X26 "Clear orange".

Assembly of the main components

I can start to add the upper wing. I can fit together the cabane struts, the fuselage and the upper wing (At this moment, the steel wire in the struts is very helpful, everything is fitted without glue).

I add some thin CA on each connection with a sewing pin.

Then I start to add the interplane struts, from the root of the wings to the extremity. I add them 2 by 2, always the same method, when fitted, I add some thin CA onto each connection.

I add the main float with the use of the struts provided in the kit, strengthened with some brass rod 0.5mm.

I replace the wing floats fixation by some brass rod 0.5mm. those provided in the kit are too fragile and have a very high risk to bend.

I add them under the wings and add the reinforcement struts, still in brass rod 0.5mm.

Et voilà, the plane is on its floats. I paint all of the struts in semi-gloss black (Tamiya X18). Now, I will start a task which seem very hard but requires mainly some patience : the rigging.

The rigging

Beginning of the rigging : prior painting and assembly, I drilled some 0.3mm holes half way through the lower wings and completely through the upper wings. Then, I use some invisible wire tinted in black (permanent marker) through the top wing to the lower wing (or the fuselage) where it is glued with a tiny drop of cyanoacrylate gel.

Then, each wire is tightened : a tiny drop of CA gel is placed with a pin just before to tight the wire into the top wing. It is hold a few seconds, et voila!!!

A tiny drop of CA superfluide is then put on the top of the upper wing to secure the gluing and to completely fill the hole.

After drying, all of the wires are cut off with a razor blade, and then filled.

Then, I mask the underside of the wing and I spray the upper side of the upper wing.

I add the cockades and then spray a coat of satin varnish to equalize the brightness and protect the decals.

After that, I apply some pastel chalk between each rib (see bottom wings), then I add the control cables for the ailerons, and the wing tip support cable.

The engine

The engine is very well moulded, you only have to add the exhaust pipes (brass wire 0.5mm). I paint it in "White aluminium" (Alclad paint), add a wash of Tamiya X19 "smoke", mainly on the top of the engine, and then, I paint the exhaust pipes. The engine is now ready to be added to the plane.

The radiator

Radiator installation : the paint is done the same way as the engine. Then, it is fitted in place with its hose made from brass rod 0.5mm in diameter and painted in "Bolt gun" from Citadel. I also added some piping between the engine and the firewall. Unfortunately, I didn't succeed to take some good pictures of them.

I tried the Citadel brand, following the advice from the discussion list of the site www.wwi-models.org/. It is my first trial with this brand and the brush application is very nice, with a very good finish when dry. You just have to find some equivalence with the names of these paints...

Last touches

Then, I add all of the rear control cable with "Dai Riki" thread 0.08mm diameter. This thread is far easier to glue than the one I usually use.

The beaching trolley

At first, I glue the wheels on the trolley, then I fill the holes and other little defects with Humbrol filler.

After that, I spray a coat of "Satin Oak" (HU 71).

Then a coat of "Matt natural wood" (HU 110).

When the paint is dry (a week after), I remove partially the last paint sprayed with a fiber glass scraper.

Then, I paint the wheels and apply a brown wash to deepen the wood structure.

The plane completed

Conclusion

The construction was very straightforward, it is a very nice kit and interesting subject. However, it is not for a beginner because of the rigging. Thank you to ARDPOL for providing this kit.