When I helped construct the ARP (Air Raid Precautions) signal box on the Luton MRCs ‘Central Works’ layout, we based the model on a prototype originally found at Town Green, Ormskirk. The finished bunker seen in the centre of the picture alongside Central Works ARP 'Box

I noticed, from a couple of images we found on the internet, that there was a large brick bunker alongside. Presumably it was used by the signalmen for keeping odds and ends or perhaps as a store by the local permanent way gang.

When I was constructing the model of the bunker, it occurred to me that this could well be a good starter for anyone who has never scratch built anything before. It is simplicity itself.

The prototype comprised of just three brick walls built onto a slightly larger concrete base. I was thinking about cutting the walls out of styrene sheet, but realised they were two bricks thick, about 9in, which equates to just over 5mm in O scale. Not having any styrene as thick as this to hand, I had a rethink. Fortunately, I had bought a ‘bumper bundle’ of assorted balsa wood some years ago from a model aircraft shop that was closing down.

I soon found a suitable piece of wood just under 5mm thick. This might appear to be slightly under sized, but once some brick paper is added that brings it up to a scale nine inches.

Obviously it could be made to any dimensions to fit the location in question. In this case I made the end walls 45mm and the back wall 120mm wide, with all walls being 33mm high.

Measuring and cutting the three walls out only took a couple of minutes, but I took care to hold the craft knife completely vertical and used as steel rule as a guide for the blade. This ensured nice square edges to the cut parts. If things go wrong, it’s probably easier and quicker to cut a new piece rather than sanding the edges square. The bunker is quite tall and although I do measure out materials when I build a model, I always like to have an O scale figure available to stand next to it to ensure it ‘looks right’. The base has been painted with a ‘Concrete’ shade of enamel. No need to be too neat at this stage as the brick paper will tidy things up.

To add strength, I was going to use a piece of plywood or styrene for the base, but since I had a lot of spare balsa wood, I cut the base from a slightly thinner piece of this instead. The finished model would be glued in place on the baseboard so strength wasn’t vital on this occasion. The base was made just a little larger than the footprint of the walls. All parts were glued together using PVA glue, again checking that everything was square. I would have used balsa cement, which dries more quickly, but I didn’t have any at the time.

The base was painted next, before applying the brick paper. I used Railmatch ‘Concrete’ and gave it three coats to hide the wood grain of the wood. The model was then set aside overnight to dry thoroughly. PVA glue was used to stick the brick paper in place, trying to match the rows of bricks nicely at the corners. A different colour of brick paper was cut to form the engineers bricks often used to cap a brick wall. Brick paper, glued in place with PVA, completes the structure. All it needs is a little weathering before installation on the layout.

Once set in place on the layout and with a little weathering and scenic material added, it looked just right. Luton MRC member Jeremy Everett added the adjacent pile of scrap and grounded van body. It brought the whole area around Central Works signal box to life.

The brick bunker was probably the simplest and quickest model I have ever constructed, so if you’ve never made anything from scratch, why not have a go at making something similar? You might surprise yourself.

An article on building the ARP box has been prepared and will appear in the next Gazette.