Junkers A.50ce Junior - Dekno's 1/72nd resin and 3D-printed beautiful little kit

 

Photo Deutsches Museum

(The completed model is here:

https://wingsofintent.blogspot.com/2023/07/junkers-a50ce-junior-dekno-172nd-scale.html

Three Junkers A.50 participated in the Challenge International de Tourisme (International Touring Competition) of 1930. The pilot on D-1862 (the machine depicted in this kit) was Waldemar Roeder, his plane being the second photograph on this page:

Flight magazine

 

The A.50 Junior was successful sports/touring plane in typical Junkers corrugated fashion, first flying in 1929 as a metal cantilever monoplane, in a time of lumbering and drag-inducing outclassed biplane pterodactyls. A truly remarkable pioneer. Built in relatively large numbers, it made its mark as a private plane but also participating in competitions and record flights (Dekno has other boxings covering those). Two of them even had British registrations (G-AATH and G-AAXB), and others flew in diverse countries, even as far as Argentina and South Africa. The plane used different engines and had small modifications during its evolution. There was even one that was converted into a biplane (D-1682)! 

Arctic Decals in Finland in a joint-venture with Dekno will be releasing down the lane the Japanese and Finnish version, with floats and skis.

Dekno, who has demonstrated a steady improvement of its creations, has achieved a wonderful little kit that combines well-cast resin parts with very beautiful high definition 3D-printed parts, the latter of remarkable finesse, something that other manufacturers that produce crude 3D-printed kits are far from achieving.

The little but sturdy box:

Contents protected in their pouches:

Excellent 3D-printed parts. You can tell that the parts are protected with tabs to minimize damage:

Well-cast resin parts:

The inst. sheet:

The resin parts are easily separated from their casting blocks and cleaned up:

The fit looks clean and good so far. This is the first interior I have dealt with in a long time that doesn't seem to need sanding down to allow the fuselage halves to close. Well done Dekno!:

The very nice 3D-printed parts. Make sure as you remove them from their pouches that you don't leave anything behind (parts or the clear vacuformed transparencies), as very small items may have separated in transit. Some modelers prefer to leave them attached until needed or painted (which is wise), I rather remove them and clean them up to have them ready, but you risk losing them doing so, as there are minute items, plus some parts are fragile. You get one spare cylinder (nicely detailed ones, by the way):

The seats are beautiful, super thin, as realistic as they get. The joysticks are there two, and again modelers should be careful not to lose or brake the parts:

A very careful wash inside a closely meshed container with a very soft brush, lukewarm water and soap. Then a gentle rinse. You may prefer to leave the 3D-printed parts still attached for this, but I like to leave dangerously:

The parts are left to dry. Watch out for the small items! some are very hard to see!

A first coat with the base colors. You can see that the cockpit interior is already partially assembled. I believe that the 1st and 3rd bulkheads that read "Behind" and "Front" should read the opposite:

 As I go through the parts I admire their quality, especially for the media. The prop (as were the seats) is thin and to scale, with a nice washout, same for the landing gear and other detail parts. Very good quality overall. It's on the modeler now to treat the parts with care while handling them. These 3D-printed parts separate easily from their bases, but need a light cleanup, which should be done gently and paying attention. 

I made a real laminated wood prop to spice up things a little:

And delicious chips:

A little detail adding rudder p.e. control horns from an aftermarket set:

Here is a downloadable PDF NACA report on the Junior:

https://ia802601.us.archive.org/11/items/NASA_NTRS_Archive_19930090396/NASA_NTRS_Archive_19930090396.pdf

The instrument panel decals and control columns are on. The seats were detailed with belts. Later on home-made rudder bars will be added:

The interior ready to go in:

Dry fit of the interior goes well:

So the fuselage halves are glued together, being careful to keep the a good alignment.

The original plane had a small flange along the nose, fuselage back, and all along the belly, and this is represented in the kit, so do not sand too much:

No problems provided you cleaned up properly the parts and did your dry-fit homework to detect potential issues:

Inserting the nose will need in my case to work a bit on the clearance on the fuselage:

All the others parts present no fit problems when tested:

The nose is the only part that required some filing and adjustments to fit properly. It has some tabs that I think are supposed to anchor in recesses into the fuselage, but that wasn't working in my sample, so I removed some of the material from those tabs to get a good fit, and used 5-minute epoxy to glue it, which allowed a good alignment:

The tail feathers and the wings are glued. The tail needed a bit of tweaking. Now, in the original there are visible gaps between these surfaces and the fuselage:

but I believe these are a bit "gappy" in the kit. Sanding very small amounts here and there I closed the gaps just a tad, other modelers may like to add a smidgen of styrene sheet over the stab "pedestal" or two strips each side of the locating hole for the stab. 

 

In any case, the fin tip has to barely touch the fuselage, something that doesn't really happen in the kit, but a conveniently placed little piece of styrene should do the trick. All the parts self-aligned correctly and fitted well in my sample, simplifying the build and speeding it up, but given the nature of cottage industry products, always dry-fit and adjust if necessary, something modelers should do with any kit anyway:

The leading edge of the wing was smooth, the corrugations did not wrap around it, so this area can be -carefully- sanded to get rid of molding imperfections if any are present:

 A coat of primer:

Landing gear legs and struts, tailsdkid, aileron horns, oil cooler, and stab struts are added. The three locations for the fuel indicators are drilled with a fine bit. A gloss black base for the metal color is airbrushed. So far so good. This has been a fun and relaxed build, that went quick as a breeze. I will be building another (the Japanese one to be released by Arctic Decals, and perhaps one more, as I just found that they also flew in Argentina in civil guise:

The oil cooler part mentioned above -that comes in the form of a "tray"- is not typical of the type, and I could only see it in the three machines that participated in the Challenge. The plane that Marga von Etzdorf flew to Japan had a teardrop-shaped one (correctly depicted in that boxing by Dekno) while others had much less visible coolers (like the photo posted a bit above) this may be due to the higher demand on the engine when used in competition or long-haul flights. As we know there were several versions of this plane also showing different details (changes in the windshields shape, for example).

The nose is airbrushed with polished aluminium, and masked, then the rest of the airframe is given an aluminium coat:

Unmasked. A coats of clear acrylic will be applied to help with the decals' adhesion:

The windshields (you have one spare per each) are carefully cut and trimmed, then given a bath in clear acrylic:

The cylinders are really the cherry on top of the cake, and an example of what good, high definition 3D-printing can do, and not the horrid Lego blocks "pixels" sub-par printing you see in other manufacturers' 3D-printed "kits":

The control cables are added to the rudder and the coamings painted. Decal application begins. The decals are of very good quality. You have to cut and trim the individual subjects. The carrier is very thin, as corresponds to a good decal, but that implies that more care is needed during application to avoid issues. First, a glossy surface with plenty of water, then VERY carefully slide the decal off the backing sheet avoiding folding. I messed up and folded a couple, they can be finicky, but managed to put them right with patience and some delicate prodding. Part of the difficulty is that they do have to be very thin in order to get into the corrugations, but the very existence of the corrugations hinders moving the decal around, and may induce folding. Patience and care is the trick. Then it's decal solution and some very gentle pressing to force them down into the corrugations if they didn't already. This may take more than one application of setting solution (it did to me). The photo shows the big regs on the wings just applied, with the carrier still wet and visible in parts. The delicate nature of the handling of these decals decided me against doing what I always do, which is to separate at least the first letter and dash of the regs to eliminate part of the carrier. If the carrier still shows later on, I may remove those big decals, print my own, and do as I normally do, again to minimize visible carrier. The walkway is my own addition after photos of the original:

Still to go: wheels, windshields, the three fuel and oil level sticks, propeller, cylinders, Pitot.

Now the model is very close to completion. The original plane seemed to have had two Pitot, one to the right of the cockpit and another over the left wing, close to the trailing edge and inboard from the aileron:

So another Pitot is made and added to the other position:

 The Pitot on the wing is not aligned with the fuselage centerline -the direction in which the plane advances, but more parallel with the flow of air over the airfoil:

 

The completed model is here:

https://wingsofintent.blogspot.com/2023/07/junkers-a50ce-junior-dekno-172nd-scale.html