Adam Carlson's 1/16th Japanese Type-A r/c Submarine, Part-8

A Report to the Cabal:

Almost three solid days of work on the tail-cone and stabilizer assembly and Adam is just about ready to clay this thing up for tool making. Then we'll build up a quick Urethane-glass mother-mold, then scoop out the clay and pour in RTV silicon mold making rubber, later splitting that into quadrants (each flange face falling along a stabilizer plane), the rubber being held in place by the mother-mold. More on that process as things develop.

I've been working the forward hull piece, taking it from wooden blank, to turned item, to contoured final shape. Here I get back to my model building roots: employing good old fashioned wood carving guided by sectional frames ... man, it felt good to whittle real honest-to-goodness wood with a knife again. I was also rudely reminded that I have wood allergies. I forgot. But, it was worth it. The last few days have been a lot of fun.

Pulling down eighteen-hour days and the boy is still smiling like a kid in a candy store! Adam building up filler flanges between stabilizer fins and tail-cone body. He's a detail nut: this master incorporates all the oblique screw holes, and rivets and panel lines that were evidenced on pictures and plans of the prototype(s). He's got AMS ... big time!

Four intermediate master stabilizers were cast up from an intermediate tool, then degreased and prepared for attachment to the Renshape 40 tail-cone.

Seen here, in the upper right hand corner, is a simply one-point stabilizer alignment jig I made for him to help him get those fins on symmetrically. Shortly after making that, Adam, usually two steps ahead of my instruction, sat down and made a four-point alignment jig. He's a quick study! In a few years I'll be serving at the feet of this character if I'm not careful.

Adam spent nearly a full days work getting the flanges between fins and tail-cone straight and built up to the correct height. Just some of the small details this guy devotes his full attention to. Here he's using forefinger to lay in Evercoat Metal Glaze filler between masking tape edges to build up the stabilizer/tail-cone flanges.

Meanwhile ... I worked on the bow master for the hull. Here I'm using my hull marking jig to lay down transverse and radial lines that denote section positions. Later I'll saw slits over these lines to accept aluminum guide frames -- these used to guide me as I take the hull piece from perfect round (at its after end) to an extreme ovoid (at the bow). The guide frames are so shaped as to produce a gentle, rational graduation of shape from one point along the length of the hull to the next.

I initially turned a slightly tapered cylinder on the wood lathe, to the plans profile outline of the bow. I then produced a flat where the transition to ovoid at the bow occurred. First, I made a drawing where I penciled in the graduated shapes from stern to bow at evenly spaced stations (the same stations marked off on the master). I then cut and modified plastic sheet section templates to match the frame shapes at each station. I used these plastic templates to finalize the line shapes initially hand drawn on the graph paper -- once happy with the form of the plastic templates I used them to scribe aluminum sheet used to make the final guide frames. The eventual aluminum frames then inserted into the master and I cut, filed and sanded the wood to the height of those frames. The end result is a master of good symmetry and form.

To the left is a length of wood that is screwed to the underside of the master. This is there so I have a foundation that can be clamped into the vice as I work the wooden master to shape.

I installed a heavy plastic 'keel' piece that runs longitudinally atop the wooden master. This is shaped to capture the desired transitional curve from after end to front end. It also becomes an easily identified central datum line as I center the aluminum frames into and onto the master.

Note that I have an aluminum frame partially set into the master. This to give you an idea of how these frames fit into the bow master. To the left of that frame you can make out three inserted frames.

(Oh, by the way ... I'll be building up a master for a rather large DARK STAR model soon. I'll be using much the same techniques on that as you see here. Stay tuned my freaky little darlings!)

I don't cut entirely through the wooden master to fit the frames, just girdle it with a hacksaw, to a depth that will permit insertion of a frame that has been scalloped out. You see the sequence of frame development here: first I use a plastic template to mark off the shape of a specific section; I then cut the frame to outline; and then scallop out the inside to fit the radial slit hacksawed into the master.

Looking at the underside of the bow master. Note the foundation piece temporarily screwed in place -- it's this item that gets clamped into the vice as I work with saw, file, and sanding blocks.

Here you see the need for the big wooden foundation -- its out of sight here, clamped between the clamps of the vice. There's no other way to hold the work in the vice without damaging it. I cut a slit into the surface of the blank with a hacksaw, to a depth a bit more than the width of the blade. As the scalloped aluminum frames had a width a bit shorter than the hacksaw blade, I encounter no interference issues as I slide the frames within the slits sawed into the master.

The only aluminum sheet frame that was not inset into the wooden master is the one that denotes the cross sectional shape at the extreme bow of the master -- it was secured with two machine screws. Lots of photographic analysis was done by me and Adam (a topic of much discussion and trepidation recently brought up at the SSM site) as we ascertained the geometry of the depression at the bow, between the over/under torpedo tube arrangement.

The drawings were done by long time r/c submariner and innovator, Gene Berger (and the best Editor the Subcommittee ever had!). Adam enlarged them to 1/16th scale for this project. As you can see, there is a wealth of detail here and the work is based on firsthand examination and photography of the Type-A war-prize displayed at the Nautilus Museum, outside the main gate of the Submarine Base, New London. Many moons ago Gene and I flew up to Connecticut just to document this thing. Gene's as hard-core as they come in this game.

You can see how the forward frame is used to define shape. I've already taken the initial passes with bastard files to get a rough shape of the inter-tube cavity. I followed this up with finer files, then sanding sticks. Right now I'm busy inlaying mono-filament fishing line to represent the radial and longitudinal weld lines on the bow master.