A Modular Layout for "O" scale trams Part 1

I have decided to start building a modular layout to run my trams on. I have always been fond of the dog bone style for exhibitions as all of the trams running are visible for all the time which is better for viewer interest. Initially it will be only a continuous loop with no point work but 3 or 4 trams will be able to tail chase each other using fairly simple automatics. Later more complex track work can be built on additional modules if I feel so inclined.

I decided that the straight sections would be 450mm deep as this gives me a reasonable width roadway and two footpaths as well. The rear scenery will be on a separate bolt on section so that the scenery can be changed without affecting the track and overhead. I wanted the front to be flat so I ended up deciding on a distorted tear drop shape for the balloon loops.

This is where track design software comes in handy. I use XTrkCad and a few hours experimenting with different ideas resulted in the track plan below. The overall size is 3' 6" x 2'6" The return loop radius is 12" and the upper entry curve is 18" with the lower entry curve being 60" The baseboards follow the curvature of the track and end up 1'6" wide where they will join onto the straight sections. The track centres are 3 1/2" where they leave the board. Pushing cardboard cut outs of Brisbane trams back and forth over this point shows no problem with overhang and no problem hitting a tram on the other track.


The last photo shows the baseboards having just been cut out with a jigsaw. The two pieces of board were screwed together and cut at the same time. I must remember to flip one of the boards over before attaching the pine under frame otherwise I will have two right hand ends. The inner tear drop shape will be cut out after the track is laid and a curved back scene will be fitted. But at the moment it is still required to provide the centre point for laying the track. The five odd shaped slits are where the timber frame passes underneath. The frame would get in the way of the jigsaw so I felt it was better to clear those areas now. They may be hard to see because the pencil is fairly light but the radial pine frames, that will be at right angles to the track, are positioned to provide support for the span poles.

Now I have to cut all the timber for the framing and the strips to form the curved edge around the module and glue them into place. Then I can think about the best part. Laying track.