Roden 1/72nd Junkers D.I "Long Fuselage"

By Pedro Nuno Soares

Background

One of the things I've always liked in Roden kits is that the team responsible for the boxing and instruction sheet design for their products not only always provide us with excellent and inspiring artwork, but also with historical notes that do go beyond the usual 4 of 5 lines of technical specifications of the original aircraft being reproduced. This I think is an evident measure of the care and interest that Roden puts into its products, that with each year that passes and with each new issue have managed to create a legion of fans worldwide, as it's easy to grasp if you care to take a look into the "guestbook" at Roden's website.

In fact, if you spend a couple of minutes reading the historical notes that Roden has included on page 1 of the instruction sheet for their 1/72nd scale model of the Junkers D1, you'll learn that this rather bulky looking aircraft drew on the experience acquired by Junkers from the first operational all metal aircraft, the revolutionary J1, on which Professor Hugo put into practice all the ideas he patented in 1912 for an all metal aircraft designed around a simple framework of duralumin tubes, skinned, not in plywood or fabric, as it was then the norm, but in corrugated sheets of aluminium.

You will also learn that as prototypes to the D1, you can not only claim the J7, evaluated during the first fighter competition held in January-February 1918 at Adlershof, but also its improved version, the d9 (in fact the D1 production prototype) that was flown at the second competition, held in July, and which embodied several design modifications that were meant, successfully it seems, to overcome the problems that afflicted the J1, especially in what concerns aileron efficiency and wing vibration, and which resulted in an order for 40 machines to be produced.

Although the notes do not say so, the D1 was also to be entered into the 3rd and final fighter competition held in October, this time with the elongated fuselage and larger wingspan that was to become the distinctive mark of the earlier production machines, later ones being shorter in length.

(Editor's Note: Bill Powers converted the Roden kit into the short-fuselage in the January 2005 issue.)

Operationally there is still debate as to whether the type saw active duty during WW1 although it is unquestionable that in the spring of 1919 "German air forces assisted the governments of the Baltic Countries in their struggle against Russia" as, again, Roden's notice informs us.

All the usual tech specs for the type are of course given in the instruction notice and as these are also available from a number of other sources (internet included) I'll move on to the:

Model Construction

I have to say I had set the bar very high with regard to this kit. Roden keeps getting better and better and I was expecting they would climb another step up the ladder with this one.

Nonetheless, upon opening the box and inspecting the parts I got a bit let down. Not that what really makes this model distinctive - the dreaded corrugations - is not perfectly solved (in fact the beauty and finesse of the corrugations has to be seen to be believed), but there were 2 things that were immediately apparent that failed to meet the high expectations I had for this kit.

Before going any further, though, I have to say that my main point of criticism towards the kit, is supported in physical evidence of the sole surviving example of the type, that can be seen overhanging from the ceiling at the WW1 aircraft cathedral at Le Bourget in France. With early aircraft though one has always to bear in mind that standardization was somewhat of a novel idea in the early days of the 20th century and, as such, a surviving example does not, most of the times, stand for the whole (even though in this case, account taken of the idiosyncrasies of the manufacturing process, and of the number of aircraft actually produced - less than 30 -one is led to believe it would be quite unlikely to have different manufacturing procedures for such a small series of aircraft).

The point I'm trying to raise is that the corrugations to the rear of the cockpit, on the turtledeck, on the kit run parallel to each other, while on the real thing they converge to the centre seam on the top fuselage panel, as can clearly be seen on this photograph.

What I find disturbing is that this replicates the drawings in Datafile #33 by Ian Stair published in 1992, while earlier drawings, by the same author, published in "Aircraft Archive - Aircraft of World War One, Vol.3" show the corrugations as per the living memory at Le Bourget.

The other thing I liked less about the kit was the fact that the fuselage sides are flat from within. That is, there is absolutely no inner fuselage modulation on this kit, and if you built it straight from the box, it'll mean that the pilot's office will lack "volume" since the rather prominent coaming only exists to the outer side of the fuselage sides. This is hard to explain but quite apparent on the kit.

Further to this problems, there are a number of lesser inaccuracies with this kit that I'll try to enumerate:

  • Exaggerated area of non-corrugated wing surface at the wing tips
  • Too thick wing trailing edges. This becomes very apparent when you try to install the very nice and scale like separate ailerons, that are much thinner in section than the wing profile
  • The wooden strip wing walks at the root of the wings are not represented
  • There is a panel line aft of the cockpit that shouldn't be there since on production aircraft the sides were covered in a single metal panel

My Model

Even though I'm not the kind that will demand absolute accuracy on his models (having pleasure while building, being my #1 driver) I did spend a good deal of time trying to come up with ways of correcting the corrugation problem in the kit that was compounded by the fact that I had no local retailer stocking the kit at hand so I had to work with the review kit and could not afford to lose any part of it, either through unsuccessful modification or any other cause.

In the end, and after a couple of unsuccessful attempts, that involved casting a replacement turtleneck in resin (that always came out short cast) and equating the use of very fine copper wire to replicate the corrugations, I decided to move on, and use the kit part as it was.

Since I was not happy with the innards of the kit, I proceeeded with thinning it from the inside, trying as such to give depth to the fuselage walls and making the cockpit coaming protrude, as it would in the real aircraft.

I did this with a dremel type device with a cutting tool, cutting the plastic on the side walls until I had walls that were thin enough to accept the thickness of new "corrugated" panels that I wanted to install in place.

Corrugated panels are not easily available in 1/72nd scale. So a bit of ingenuity was needed: using the corrugated outer side of the fuselage as a mould I applied a piece of kitchen metal foil onto it and rubbed with a q-tip, until I had a section of foil with a neat embossment of the corrugations.

Foil is quite flexible and prone to lose the details therein embossed so I liberally applied CA onto the rear side of the foil, and left it to dry for a full day.

The next day I had pieces of "corrugated" foil that I glued onto 10 thou card. The "corrugated" sections thus achieved were then cut to shape and glued onto the sidewalls of the cockpit, what resulted in a much more convincing surface than the original side walls.

I followed the kit's instructions and assembled the whole fuselage, what can be a tricky business due to the fact that the fuselage is composed of a 4 part assembly ( 2 sides, top and bottom), care being needed to ensure that the correct profile and section is maintained throughout the assembly process.

I was not happy with the coaming as I have already said but I think I overshot in trying to correct it. I used insulation from telephone wire to define the borders of the coaming and filled it all up with miliput, that was later sanded to shape. In the end I suppose that in order to try to correct an understated coaming I came up with an overstated one, but wrong as it might be, I find it doesn't look that far out of place.

After gluing all the main assemblies in place I was ready to start painting and as usual I gave the model a rinse in dish washing detergent. While doing this, an aileron went down the drain and since I had no way of readily acquiring a kit I decided I'd try to cast a resin one.

I created a mould in RTV rubber and successfully cast a new aileron in resin, that was immediately put to use.

It was now time to paint the model and out of the paint tin drawers I came up with the following solutions for an aircraft that, according to photos and surviving registers, was mostly painted lilac/green/light blue:

Xtracolour German WW1 Topside purple X242
Humbrol 75 Bronze Green
Testors Flanker pale blue 2130

Masking the upper surfaces for the irregular green patches over the mauve surface was achieved with maskol although I found out this was far from being the perfect solution since removing all traces of maskol wasn't easy.

Conclusion

As I said I had high hopes for this kit. They were frustrated due to a number of engineering problems that I suppose can be attributed not only to "following the accepted plans" but also to the problems of trying to replicate in injected plastic the distinctive corrugated panels, what I suppose is not an easy task in 1/72nd.

All in all, and now that I have the completed model in my display shelf, I have to say that I'm certain that even if not 100% accurate, you'd not confuse this model for anything else, and again Roden is to be congratulated for bringing into the mass market a kit of a model that until now, in 1/72nd scale, had only seen the light in vac form, thus exponentially augmenting the hypothesis of seeing D1 models on exhibition and competition tables in the years to come.

Thanks to Roden for the review model.

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