RC Sci Fi: Sony Spaceship Two part 1

We had this old Sony Micro Hifi thing which was always a bit problematic. The CD door which was electrically operated broke quite early in its life. I fixed it a couple of times, then recently the belt broke making the door impossible to operate. Additionally it started making a crackling sound and it was destined for the bin. I was on my way to throwing it out when I turned it sideways... and... inevitably I started a new project.

The original Sony spaceship I made in the late 1990s has remained the most visited page on this blogsite.

Sony Spaceship from the late 1990s.

Will this new Sony inspired spaceship engender the same level of interest? Probably not but it has sparked enough enthusiasm in me to drop everything and make a start on this project.

I started by making a rough polygon model of the Sony Hifi casing on the computer and then roughing out a complimentary shape for the rest of the scratch-built hull and engine section. The aim here is to get a shape with pleasing proportions that looks like the found part (the Sony micro HiFi) was designed for this rather than the other way round.

I then used these rough shapes to generate hull bulkhead templates. I do this by positioning a virtual camera adjusted with near and far clipping planes to see only a very thin slice at the bulkhead positions and doing a screen grab. I have also added two planes, one vertical on the centre line and one horizontal as a datum for alignment. These screen grabs are then aligned, cleaned up in photoshop and printed out fullsize on paper for cutting out.

Thin slice through the low poly model around the engine section.

Engine bulkhead shapes cleaned up and aligned in photoshop.

Middle hull bulkhead shapes in photoshop.

Top view showing the relative bulkhead locations.

In this case I stuck the paper printouts on a piece of cereal box cardboard and cut templates for tracing onto 6mm foamed PVC. This is easily cut with an OLFA snapper knife freehand.

You will note that I left the engine section segmented with straight line segments but the rest of the hull I rounded out with smooth curves. I do this using a flexible steel ruler or anything that can act as a spline. I hold it in position bending it so that the curve passes through the polygon points of the bulkhead shape and get someone else to trace the line directly on the cardboard template. Of course it would be possible to do this in CAD.

The PVC bulkheads are superglued to a wooden spine to which galvanised 15mm water pipe flanges are attached top and bottom, my usual mounting system.

Prior to attaching the bulkheads I needed to prep the Sony Hifi casing by removing the innards and the speaker cloth. Removal of the speaker cloth panel revealed an interesting hexagon pattern. All the holes were filled with styrene sheet. As you can see the casing itself is made from styrene. The recycling letters HIPS molded on the inside mean High Impact Poly Styrene so it glues really well with the usual thin styrene solvents.

The front panel has a nice little window which will become the cockpit windscreen. Below half the holes have been covered inside by styrene sheet. On the outside some kit part detail will eventually be added to the blanked off hole recesses.

The whole Sony unit then had to be securely mounted at the head of the spine. I laid wide masking tape over the base of the unit and did a pencil rubbing to reveal the exact shape. The masking tape was carefully peeled off and transferred to some plywood to be cut out on the bandsaw.

The plywood was then glued and screwed to the base of the plastic casing and then screwed to the spine making a very solid join.

The engine section top surface and engine well was then skinned in 1.5mm styrene sheet. I decided that the engine well was too deep and glued in some spacers and a made a new engine well bulkhead to make it shallower.

The engine bells were 3D printed from a free slightly modified STL model I found online.

12 volt LED lighting was added to each engine nozzle and tested.

I installed wiring to power the engine lights and cockpit lighting. As usual I added a switch so I can turn off the engine lights separately.

There will be two DC power connectors added one top and bottom. The placement of these will be determined when skinning the hull.

I figured the scale was going to be 1/72 so placed a figure in the engine bell for scale. I may change my mind and up it to 1/48. When I start on the cockpit interior I will get a better idea of what fits and looks right.

1/72 scale figure in the engine bell.

The shape of the underside surface of the hull is a compound curve and I an using sheet material to skin the bulkheads which only likes to curve in one direction at a time. To get around this problem I have to cut darts, to use a dressmaking term, to allow the flat material to bend both ways. A dart is simply a thin wedge shaped cut where the cut edges are drawn together to form a compound curve. I am using 3mm foamed PVC which is much more flexible than styrene but nowhere near as impact resistant. The foamed PVC tends to bend in one direction more easily than the other so the tighter radius is biased to the easier side. The darts are temporarily pulled together with masking tape and thin superglue dripped into the seams pushing them tight together. The thin super glue loves foamed PVC and it goes off in seconds making an extremely good bond.

Close up of the darts in the 3mm foamed PVC sheet

This pre curved sheet is then superglued to the bulkheads. You will note that I added a strip to reinforce the ends of the bulkheads and give a solid continuous edge prior to gluing the skin on. The skin was left oversize and trimmed back flush after the glue had set. I use a small razor plane to trim the edges close to flush finishing up with a flat sanding stick.

The other thing to note is my recent stock of foamed PVC has been recycled from old signs which were being thrown out where I work, at a science interactive exhibition centre.

Before skinning the undersurface of the engine section I needed to add detail to the gap between sections before it became too difficult to access the space. Recessed detail always looks good on a spaceship so I went to town on filling the void.