The Dove part 2
from David Merriman

METHODOLOGY

Establishing a methodology to a model building project starts  with definition of the steps, and an efficient ordering of those steps.

With a kit, the methodology was prepared as an initial part of the production process: the masters, tools, and kit parts were planed, fabricated, employed to produce kit parts, and a neat set of instructions and markings were stuffed in a box - all this done for you by a second party well before you wrestled with the plastic wrap. The kit manufacturer (many resin/vinyl kit producers are woefully delinquent here) extended the methodology to extend, this time into your hands, in the form of the instructions provided with the kit.

The DOVE featured in the movie Journey To The Far Side Of The Sun had a design reflective on on-going lifting body research in America and Russia at the time of the movie production - the late 60's. Here, we see a grainy photo pulled off of an actual 35mm copy of the film. This particular scene showing the VTOL capability of the  DOVE as it lifts off its ground handling dolly, retracts its landing gear and prepared to take off for an orbital link-up with its parent craft, the PHINIX.

Production stills like this are invaluable resources for the model builder. Not only can we discern dimensional information (with some  correction for lens and aspect), but also some useful information about color.

These five-view drawings of the DOVE were prepared by Philip Rae a number of years ago. They first appeared in the Anderson fan publication, SIG. The five orthographic projections of the subject permit direct pick-off of measurements from plan to model part. All I had to do was enlarge Phil's drawings in a copy machine to the working scale  (1/48) and I was ready to build. Not often is the model builder presented with so accurate and complete a study of the prototype as the work Phil did here.

Would I build One Or More Models Of The Dove?   With A scratch-built model the techniques you choose to build the subassemblies is sometimes driven by how many identical  subassembly are needed. For example, the wings, air brakes, engine nozzles, air-brake wells, and so on were items that I needed multiple copies of. Why go to the work of scratch-building the more complicated structures several times over if I could simply build one master, make a tool off it, and then quickly cast the number of copies needed to achieve the model?

Preliminary examination of the job already dictated the creation of 'tooling ' to achieve the majority of the subassemblies needed to realize a completed DOVE model. Knowing that, it was a simple matter to elect to go with another reproducible technique to achieve the single piece  structures: the vertical rudder/stabilizer, hull, and cockpit. Producing those structures in tools would enable me to produce complete 'kits' of the DOVE for later projects and friends.

I decided to build masters, tools, and finally, cast resin, cast metal, GRP, and acid-etched DOVE parts - I could make as many like subassemblies of the DOVE as I wished.

Procedural Sketches

The 'procedural sketch' is an important tool needed by the accomplished model builder to help him formulate the methodology of construction. Here we see several  proposed fabrication steps being analyzed on paper - long before any physical work had commenced. The procedural steps, if you will, are to the Model Builder what kit instructions are to the common kit assembler.

In support of establishing the methodology I began to make a series of sketches. Some with a rough perspective drawing of the DOVE in a selected  attitude. From each sketch, I established one or more procedural guides. These 'pencil studies' helped me to determine which fabrication technique and what type of material to employ for each specific master.

The  DOVE's hull master is considered, in its entirety, as a subassembly. But, inserted and attached to it would be other items, fabricated off hull  but later integrated with the hull before creation of the hull tool  (mold).  Some of these insert items would have to be thin walled - the attitude control jet and retro-rocket wells, for example. I needed two of each. Also, the two air-brake wells (I wished to display the finished  model with the two air brakes deployed) would be inserts inlayed atop the after portion of the hull.

The shape (compound curves for the thruster wells, simple box for the air-brake wells) of these inserts dictated the technique of construction as well as the substrate chosen. The thruster wells would be vacuformed over wooden plugs; the rectangular air-brake wells would be built up from plastic sheet over a form; and the  three 'tunnel' pieces (representing vertical jet engine intakes and nozzles) would be formed by pushing a cylindrical 'plug' into a hot piece of styrene sheet, squeezing it through a circular 'die', thus forcing the pliable plastic to conform to the shape of a tube.

Three techniques right there: simple sheet but joint assembly, heat forming with mechanical assistance, and heat forming with air pressure assistance (vacuforming in this case).

Keep in mind all this work was done well before I made the first cut of material in the shop - success is in the planing AND the execution!

A more detailed graphic study of the proposed operations dealing with just one subassembly is presented here. Deceptively  simple of form, the cockpit presented one of the most challenging fabrication jobs. As you can see, I reduced this task to three specific phases, fist to cut out blanks of dense modeling foam and to mark them, with the aid of templates lofted off the plans; assembly and then cut to plan and profile the blank; and finally to refine the shape of the cockpit to the sections I produced from careful study of the  Phil Rae orthographic drawings and production stills of the full scale stand-in and miniatures of the DOVE.

Other procedural sketches dealt with just one subassembly. For example, the cockpit: Though this would later be integrated with the Hull master, the  cockpit is complicated enough in shape to warrant special attention. Methodologies of blank layout, assembly, initial shaping and desired shape were illustrated. Again, this type of sketch simply helps me determine how  to perform an operation and suggests what materials to use as a substrate. The key to the process is the vast experience I have with techniques and materials - something gained only through constant practice of the  craft. May I point out here that the procedural sketches are not isometric graphic representations, so are not useful for pulling actual measurements, that is the job of the orthographic projections presented in the four-view and sections drawing.

Another procedural sketch outlining a rational order of steps to accomplish a specific subassembly, this time the wing master (from which a rubber tool, and eventually two resin copies would be cast). It outlines how a lofted template would be used to mark off the plan of the wing, how I would establish the maximum cord and  span line with the aid of a Machinist's surface gauge, and finally how I would shape and detail out the piece with file, sandpaper, and chisel.

Another example of how the procedural sketch is used: The problem of making the wing was quickly worked out in graphic form. First I would cut a template from an extra copy of the Phil Rae drawings, using that to mark the wing outline onto the face of a piece of dense Poly-Shape foam. Since I had to cut a symmetrical 'airfoil' section to this tapered wing, I  needed to establish on this blank the central running plane shared by the tips, leading and trailing edge, and root. I could have achieved this demarcation line in one of two ways:

I could have cut out two thin  blanks of Ren-Shape and laminate them together after darkening the inboard face of each with a marking pen. The darkened glue plane in the center of the wing, running span wise, could not be obliterated, no matter how much material I removed with knife or sandpaper. This is the preferred, though time consuming way of establishing a clearly identifiable demarcation plane within a master/part.

However, I elected, in the interest  of speed, to make a single blank, and to mark out the demarcation line with the aid of a machinist's surface gauge. This is done by mounting the surface gauge and blank on a perfectly flat working surface. Sliding the  surface gauge back and forth, with its stylus set to a height one-half the thickness of the blank, an engraved line is cut around the blanks perimeter representing the cord center of the wing master. Running an ink pen into the very narrow engraved line highlighted it. I would then use file and a sanding block to cut the blank to airfoil section, stopping at the perimeter line.

As the wing procedural sketch progressed I also  finalized the means of how I work the piece to achieve the gap between the aileron/elevator control surface and the rest of the wing. Though a non-practical surface on this display model of the DOVE, by careful use of  knife and gouge would create an apparently practical division between flying surface and control surface. All this worked out on paper.

How many kit assembling operations have you screwed up because you failed to think through the entire sequence of steps before sticking parts together? Kit supplied instruction be damned!

I don't make many shop mistakes nowadays - I first blunder through and finalize the methodology on paper, only after I'm satisfied that things are as refined as I and the tools and materials on hand will permit, will I enter the shop and start construction. This is the way you should approach your modeling.err. kit assembling too.

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