[subscribe]
Forums -> Terrain Making Wiki

Sci-fi Lookout Tower


Sci-fi Lookout TowerThis piece by 'Confirmed' makes use of Plastruct open-web truss in an unusual but very effective manner... and has LED lighting too!

This was scratchbuilt from 0.8mm styrene sheet. The shapes were marked onto the plasticard using a pencil, then scored using a scalpel, and snapped. The edges were scraped using a scalpel where necessary to make fine adjustments, or to smooth things off. The pieces were assembled and glued using pure methyl-ethyl ketone (MEK), and small brace-pieces made with plasticard and glued just below the joint location.

The body was made in two sections - the box on the outside, then an insert slotted into the top to make the tops and insides of the walls, and the step. The windows were useful to further stengthen and support the walls. The joints were scraped again with a scalpel to remove excess plasicard, and to make the joint flush and invisible.

The small ladder inside was also made with small hand-cut strips of plasticard.

The Legs

Sci-fi Lookout TowerThese were very simple, and are lengths of suitably shaped Plastruct superglued to the flattened corners of the main body.

The aerial was made from a small piece of girder from an old model kit, and the generator from a transformer, formerly a (definitely necessary) part of a video recorder.

The base

The simplest part of the structure, this is simply a piece of old chipboard rescued from a local ditch and formerly someone's kitchen, attacked sedately with a substantial hammer and a wood chisel. The piece was bashed into the required shape, then mangled with various implements to remove the top surface to make craggy bits. One of the off-cuts was glued back onto the top of the chipboard to give some height. The platforms that the legs stand on were carved into the chipboard using a hacksaw to get the smooth square finish. The base is therefore effectively carved from one solid piece of chipboard.

Sci-fi Lookout TowerSome washed gravel was added to enhance the texture, and was glued with PVA.

Plastic beading (used for curtain tracks or something similar) with an equilateral 'L' shaped axial cross-section, was cut to lengths matching the sides of the square plinths, and the pieces were glued to the plinths using superglue to create frames for the attachment of the legs to the base. These can be seen in the picture above - the beading is white, and surrounds the places where the legs meet the base (which in the picture, is filled with red wood filler). The legs were attached, somewhat unconventionally, using instant wood filler applied with a stick and a knife. The small frames were not quite filled, so that another, smoothing layer of filler could be applied to finish the surface. After hardening, this was filed down so that it was fairly smooth. It should be noted that small holes were drilled partway into the plinths to aid keying of the filler.

LEDs

Sci-fi Lookout TowerPerhaps the most interesting part, and an (admittely rather blurry) photo of the LED mounts can be seen to the right. The LEDs used were small, square, white LEDs saved from disposal by a contact in the semiconductor industry. In order to attach them to the structure, a length of 8-9 mm external diameter plastic tubing was obtained from a DIY shop.

The tubing was cut to size, to fit between the legs of the structure, and the ends bevelled appropriately. Marks were made at the desired locations for the LEDs, and small 4mm diameter holes drilled through ONE WALL of the tube at these points. A pin vice and a tiny drill bit were then used to drill pairs of holes in the wall opposite those already drilled, such that a pair of electrical PCB mounting pins to be used as contacts for the LEDs could be pushed through, and held in place with superglue. Wires were soldered to these pins, and pushed through the tube to protrude at one end. LEDs were then soldered to the pins where they protruded from the tube, holding them in place. The wires were fed down through the tubes, and down another similar tube into the base of the structure.

Sci-fi Lookout TowerThe two LEDs on each tube were wired in series, and were then connected in the base to create two circuits, connected in parallel, each consisting of four LEDs wired in series. This was done in the base using a set of jumpers, so that the circuit could be reconfigured if requred. No resistor was used, as the circuit was balanced to run the 3v LEDs from a 12v supply. This is not really to be recommended because, although it works, it increases the chances of damaging the LEDs.

For the flashing beacon, a 555-timer chip in astable configuration was used with a plain red LED. The beacon observes roughly a two-second off-time to a 10ms on-time (simply put, it flashes on briefly every two seconds). A forthcoming tutorial will explain the connection of this circuit in more detail.

All of the electronics were mounted into a hollow carved in the chipboard base.

Finally

The pipes were decorated with handcut strips of plasticard, which were wrapped round and superglued at intervals to give the apparent strengthening ribs.

The large ladder was made from brass rod, notched at intervals, with small lengths of copper wire soldered into the notches. Any gaps in the whole model were filled with milliput, which was filed to shape on hardening.

Painting

Sci-fi Lookout TowerThe whole thing was painted matte black using two coats of solvent-based roof-beam paint. Everything was drybrushed using craft acrylics, graduating from black to mid grey all over (except the metal parts) in around 6 coats, and final applications graduating from mid grey to light grey for the main structure, and coffee for the base. The metal parts were drybrushed lightly with silver. Diluted ink was applied at various points on the base for weathering, and green drybrushing applied to simulate moss.

Gloss spray varnish was applied, followed by matte, and the base was flocked sparingly with Javis Autumn mix. Good quality silver paint was used to pick out areas of the metal, which were then painted with a diluted solution of acrylic gloss varnish to give them lift.


Forums -> Terrain Making Wiki