Scratchbuilding SKYDIVER from Gerry Anderson's U F O____.._..__________ Back to INDEX

Gerry Anderson has made a lot of popular television shows and one of his best was 'UFO', made in 1969. This series was his first to use actors instead of puppets and told the story of Earth fighting off an invasion by aliens in the not too distant future of 1980. The effects, by Derek Meddings, were even more impressive than before and featured some excellent hardware designs by both Derek and Mike Trim.

One of my favourites was the Skydiver submarine that came with the detachable rocket powered aircraft Sky One. To film the SFX shots the studio used two complete Skydiver models (30 & 60 inch) and one further large scale (24") Sky One.

The Build David Sisson
See also Science Fiction Modeller Issue 9 Feb 1992 and SF & F Volume 1 Number 1

To draw my blueprints I had profile photographs of the small 'Diver' model, which is reasonably similar to the big version, just a little bit rounder with the only real big difference being in the shape of the two rear engines. The three Sky One's however have major differences and although most of my photos were of the big and small versions I tried to copy the medium sized model as I believe it has the better overall shape.

To construct the main Diver section I took my side profile blueprint and drew a series of horizontal lines across it, starting at the top deck and working down. With half inch spaces between each line there were ten lines in all. The next step was to cut ten sheets of half inch balsawood to the various lengths now indicated on the plan. Then from my top view blueprint, I obtained an outline of the upper deck which I then cut out of the top two layers of wood. The outline for the whole model was cut from the next five layers with the lower hull taking up the remaining three sheets.

Once this was completed all the layers were glued together to form the basic shape of the model which was then cut and sanded down to the required finish. The two engines and the conning tower were made separately, with the tower this time using vertically cut sheets. Finally the soft wood was coated in two layers of SP113 Epoxy resin and sanded to a smooth finish.

Seven plaster casts were now taken of the various parts, one for the conning tower, left and right sides for the hull and then top and bottom casts of the engines. Then the model parts were cast up in fibreglass, the parts superglued together, all the minor air holes and blemishes filled and then sanded smooth again. However I wasn't actually happy with the finished shape.

So I made another set of plaster moulds of the hull and then produced a new casting from just a thick layer of P38 car filler. I then spent a good many hours reworking the contours of the hull to get a better shape to it. The results were a definate improvement so I did the same for the conning tower and engines. Then using the new P38 masters I made new plaster moulds and cast up another set of parts from a thin layer of fibreglass.

The edges were trimmed and then the hull halves glued together. More thin strips of fibreglass matting and a small amount of resin were added to the inside to strengthen the join, with electrical tape applied to the outside to prevent the resin from leaking out of the gaps during the process. Spray filler, car filler and knifing putty were used to get a perfect finish.

Now all the various recesses had to be marked onto the hull and then drilled out. The holes in the upper deck are filled with Plasticard and kit parts whilst the rectangular side vents had metal mesh placed inside. The row of recessed vents around the front end were slightly troublesome; here they were first drilled out completely and the edges filed square, then plastic strip is placed in the hole at the angle required and filler pushed against it from the inside. When the plastic is removed the recess should be the perfect shape.

On this model in the pictures I made a slight mistake, the side-bulges at the front of the engine areas have grooves in the surface - its much easier to cast these parts separately and then cut the grooves in than actually cut grooves into the finished model.

All the fins for the model were created in solid P38 car filler. This was done quickly by squeezing the filler between two plastic sheets cut (slightly bigger) to the shape of the required fin. The two sheets pivoted from the trailing edge with plastic spacers placed between them to ensure the finished part was the correct thickness. All I had to do was sand down the parts and round off the leading edges. The fins were superglued into position with a bit more filler to blend them in.

The trademark modelling technique on the UFO miniatures was the use of tapes to quickly create surface detailing. These should be Letraset Letraline tapes but they can be expensive and here I'm just using strips cut from A4 paper label sheets, which are fine as long as they don't have to curve too much, otherwise you have to use the Letraset ones. Once they are in position it's best to paint the model just to help seal them into position.

The big difference between the two Diver models is that the large one has just plain round propulsion tubes. I think they look rather simple, and not very futuristic, so I always chose the more oval versions of the smaller model.

The Sky 1 model was made in a similar way the the Diver section. The fuselage was cast in two halves from fibreglass with solid cast P38 wings. The fluted front section was made separately, as again it is much easier to cut in the grooves that way. The front opening is made from a plastic kit part from the Airfix Saturn Five rocket. Many people often build Sky 1 with a flat-sided fuselage, which never looks right as it should be very round in places, especially towards the front.

The pilots cabin was heat-formed from thin plastic sheeting over a master carved from wood. Another partial inner moulding was made from transparent plastic to create the windows. The side fairings and gun housings were cast in P38 mixed with resin, using a heatformed plastic piece as a mould. The main rocket pods and engine tubes were cast using rubber moulds, as its very difficult to drill all those rocket tube openings into two different parts and make them look exactly the same.

Fitting Sky 1 to the Diver is the trickiest part of the project. First of all I temporarily glue Sky 1 to the Diver section - but without it's wings attached. Then once I'm sure that it is on straight I can glue the two engine tubes into the holes on the front of the Diver. These tubes are in two parts, comprising a small section for the Diver and the rest for Sky 1. These tubes have to be lined up with the fuselage of Sky 1 to make sure that they are straight and that the wing can attach to the fuselage at the correct angle. Car filler is then applied to the inside of the Diver shell to lock the tubes into position, and then when that's set the wings of Sky 1 can be glued to the fuselage. More filler then blends the two wings to the hull and gives them a bit more strength. Next the temporary glue bonding the two craft together was broken and the models separated. They were then refitted to check that nothing had moved, then the engine tubes could be cut off from the Diver, trimmed to the right length and attached to Sky One.

It sounds easy but it is rather tricky and must have proved a problem back in the 1960s when the original models were made. If you look at a side profile picture of the Sky 1 (on the large Skydiver model) the bottom of the craft seems to angle downwards towards the rear - but the bottom is actually flat and it's the engine tubes that are angling downwards at the front!
Unfortunately due to the sleek design of this vehicle there isn't much room to make any mistakes with the contours of the Diver. If you don't get the front of the Diver 'just right' then the two models simply will not line up correctly and you will end up having to compromise the position or angle of Sky 1's wings.

Finally the model was painted using Acrylic motor car spray paints, with the main colour being Ford Oyster Gold Metallic. This model does take a long time to paint due to the high amount of different coloured panels, which all require large quantities of masking tape.

The periscope was made from brass tubes, modified kit parts and plastic. It is only attached to the model with a small drop of superglue which allows it to drop off when 'knocked' instead of snapping and causing damage. The conning tower is left as a separate piece and attached to the hull, like the original model, with a screw (slot-headed for complete accuracy). This allows me to gain access to the interior where I have a threaded steel rod that goes into the back of Sky 1 and attaches it to the Diver section.


A large amount of weathering consisting of mostly ground up graphite pencil and black powder paint was used on this model to tone down the bright gold paint. This was applied using either a brush or just a finger against the edges of masking tapes, then sealed on with clear laquer. Then the process was repeated, building up the effect in layers until the required amount was achieved.

Coloured lines are Letraset Letraline Flex tapes. Luckily I still have a supply of white Letraset lettering for the markings.

On this model I decided to fit small metal loops into the surface as attachment points for support wires. I've started doing this with a lot of models lately as it allows me to hang the model with ease.