Building an 'Improved' Wallace RC 1/16 scale KAIRYU Suicide Submarine Kit, Part-13

A Report to the Cabal:

The sail of the KAIRYU features several access hand-holes and plates. These access points obviously used to maintain the equipment and devices within the sail fairing. On such a huge scale model even the mechanical fasteners used to secure such panels would be apparent. To do the model justice both the engraved lines of the access panels and hand-holes, as well as the fasteners had to be represented.

The sail on a model submarine catches the eye much as the cockpit on a model airplane.

So, it behooves the careful model builder to lavish as much attention on the detailing of the sail as he can. First impressions are important.

And that's what the next few installments of the KAIRYU article will be about: detailing the sail. Here we'll look at the technique of scribing to render the deeply engraved lines that represent the sail access panels. And we'll look at the layout process; the methods used to transpose identified details from plan and photos to the model.

Scribing The actual engraving of deep lines within a models surface is basically a scraping operation; a tool is dragged along the surface of the subject as pressure is applied, and the tip of the scribing tool (scratch awl, scriber, stylus, are just some names given to the scribing tool) digs into the work. The tool is most often guided on its journey over and into the surface of the model by resting one side of the tools shank against a guid to control the direction the scribing took takes during its travels. Almost never will you 'freehand' the scribing tool (we'll leave that very special craft to Jewler's). In almost every model building situation that requires an engraved line, you will employ a guide of some kind to direct the path of the tool -- be that guide a simple straightedge or the most complicated stencil pattern.

You will learn, quickly, how vital it is to know just what material you will be cutting into as you perform the scribing operation; you have to be cognizant of the substrate into which your tool will be cutting (abrading is the right term, but convention has settled on the term, 'cutting'). The ideal situation is to cut into only one type of material --doing so limits the problems encountered if you cut into layers of different type of materials; materials that present the attendant hardness and stress fracturing problems unique to each type. Differing substrate materials is the norm in model building, not the exeption. Sorry. Get used to it!

Proof of point: the work here involves engraving lines through primer, filler, and GRP (a very challenging material to engrave with accuracy and maintenance of an even line width).

However, with tool control, a light touch, and practice, one can learn to scribe through multiple layers of different materials. The objective is to lay down uniform, well defined engraved lines. Hopefully, this little discussion will help you along in achieving your own ability to scribe a model. The key to success: Attempt. Analize results. Come up with solutions to problems identified. Attempt again integrating solutions. Refine techiques. And, PRACTICE!

Layout Layout is the practice of transferring dimensions and locations from drawing, photo, or other document (even lofting off directly from a prototype) to the surface of the model. Usually you have a plan (orthographic drawings of the subject, to the same scale as the model) from which you will pull dimensions and locations with dividers, transferring those points straight to the model. This was partially the case with the Wallace RC kit of the KAIRYU: a full-scale set of plans were provided, and it was from that document that some of the detail items were lofted off and transferred to the model. Not on the plan were the location and shapes of the access panel lines -- these were derived from photographs of an actual KAIRYU vehicle; a war-prize, currently on display at the Nautilus Memorial Museum in Groton Connecticut. Incidentally, those photos are also available from Wallace RC as a 'supplemental package', and are a must-have if you are a detail freak like me wishing to build and detial your own model of the KAIRYU.

Stencils and Stencil Making The simplest stencil is a straightedge, a variation on that is a French curve, or the circle stencil, and the many variations of ovals, squares, and multi-sided shapes. The stencil materil should be thin to limit scribing tool 'drift' --that drift a consiquence of the shank end of the scribing tool, being held at any angle but perpendicular to the work, pivoting off the high edge of the stencil bearing surface, distorting the engraving. The stencil should be made of a material hard enough to resist deformation as a consiquence of the pressure applied to it as you hold the scribing took against its edge. And the stencil should be mailiable enough to be bent, without breakage or deformation, to accomodate compound curves unique to that portion of the model you wish to scrib.

There are many different materials from which commericially available stencils are made: Those intended for drafting duties are typically made from plastic. You'll find those at stationary and art supply stores.

Verlinden produces an excellent thin, stanless steel, set of stencils, of just about any shape you will require in various sizes, http://www.best1hobby.com/Merchant2/ merchant.mvc?Screen=PROD&Store_Code=168&Product_Code=VP0281 . I used those on this project.

And, of course, you can make your own stencils. I've cut mine from plastic, brass, even aluminum sheet. I even acid-etched my own stencils. All this done to shapes and sizes that are not available commercially. I'll show you below how both commercially produced, and homemade stencils are used to engrave a model.

Representing Fasteners The panels represented on the model by engraved (scribed) lines would not be complete at this big scale unless the array of machine screw heads, used to secure the real plates in place, were also represented. Like the little stern stabilizer linkage access plates, I represented the screw heads by simply drilling small, shallow holes -- the shadows thrown by the holes good enough to register to the eye as 'something' akin to fasteners. Some special tools were used to space and bore these holes, I'll cover that too.

Taking measurements off the Wallace RC kit plans of the KAIRYU and the photos, I used a set of simple dividers to loft off the plans and a set of proportional dividers to loft off pictures -- when picking measurements off pictures (selecting only those that present an angle perpendicular, or nearly perpendicular, to the plane of the surface being measured) you first determine the ratio of each picture to the scale of the model and adjust the arms of the proportional dividers accordingly. Keep a record of that ratio for each picture and keep it handy -- you have to reset the proportional dividers each time you pick measurements off that particular picture.

Four dots, representing the width and height of each access plate were marked onto the sail. Those dots later connected forming the four lines of each panels outline with the aid of a pen loaded surface gauge (otherwise known as a waterline marking tool) and right-triangle. Of course the base of the sail was shimmed so its periscope (representing the vehicles true vertical) sat perpendicular to the baseboard used as the reference plane for the surface gauge and right-triangle.

A circle template was used to mark off the side portholes and single footsteps. Elliptical drafting stencils were used to mark the ovoid access plates.

My scribing tools are simply jeweler's files ground to a point -- nothing fancy. Save your money and don't buy the 'special' scribing tools sold in magazines, they're crap!

Here you see some of the stencils (Verlinden metal one's are the best), sandpaper, sharpening stone (used to keep a point on the scribe) and the 3M double-backed tape I use to keep the stencils from sliding around on the work.

First I use a straightedge -- a piece of brass strip with its inboard surface bonded to a piece of sandpaper to make a non-slip surface to engrave the four lines of each square shaped panel. I then use a circle stencil to cut in the radius at each corner of an engraved panel. Here you see two pieces of double-backed tape laid down on the sail, ready to stick the stencil temporarily in place as I scribe in the quarter-circle needed.

The only 'custom' stencil needed was this ovoid I cut from aluminum -- I had plastic stencils, but this one had to be bent to adopt the compound curve up near the bridge well.

Aluminum is easy to drill and machine and it is bent with little effort, making it the ideal material for this specific job. To check evenness between this upcoming engraving and the one already engraved on the other side of the sail, I first marked the tentative location with a pencil, to check for symmetry. In fact, in this example, the pencil ovoid was way too far foreword. Knowing that I corrected the position of the stencil when I next put it down to engrave the work.

The position was so awkward that I elected to glue the stencil to the model. No biggie, what damage removal of the stencil causes on removal is easily repaired with some spot filler. I used baking soda as a grout and saturated that with thin formula CA adhesive -- just enough getting through to stick the stencil to the sail, but not so much as to cause massive lifting of the primer was the stencil was popped off. No was is this stencil going to shift during the scribing operation.

Of course there were plenty of 'overstrikes' (scribed lines that exceeded the boundaries of the desired engraved panels) that had to be filled using a 'hot' mixtures of Evercoat Metal Glaze and cream hardener. This goo was quickly rubbed into the engraved portions of a panel. Before the filler hardened I quickly re-engraved the panel with a very light touch to open up the portions of the panel lines I wished to maintain. You see some kerf hanging off a freshly chased engraved panel.

A second back-up coat of filler to insure I got all the overstriked areas filled. This one with a different color cream hardener so I could see what layer covered what ding.

Later a wet sanding with descending cuts of sandpaper removed the excess filler.

Dividers were used to establish the spacing between the holes I would drill within each panel. These holes representing fastener heads. A special two-pointed spacer tool was used to insure that I established a consistant distance between each hole and the engraved panel line. With these two tools I was able to achieve a precice spacing of one hole to the other as well as keeping all holes a constant distance from the engraved outline that represented the panel.

First I marked within the panel using the dividers; then the spacing tool; then I deepened the scratch-marks with the scribing tool; then, finally, I drilled a shallow, small diameter hole at each punch mark to represent the actual fastener.

Ellie drilling the small, shallow holes that represent the panel fasteners. Small work! Damn, girl! We're get'n old!

The completed scribing and fastener work. Next: the louvers!