Trackplan
approximate size is shown by 1-foot grid
The plan is a bent oval with a passing siding and a spur track. It is made with O-27 track (mostly Marx). The track switches (turnouts) are Marx metal switches from the 1950s. Though electric switches could be used, I decided they weren't worth the extra wiring. The Marx plastic switches could be used also, but because the layout shares the floor with two dogs, I was afraid that the delicate levers would be broken off.

I built the layout by eye, but drawing the layout after the fact showed that I needed three fitter pieces to make the track geometry work well (I had only one). These are shown above as short purple sections. The lack of fitters in my actual layout resulted in trackwork under tension that was constantly working itself loose at different points, causing frustrating breaks in the track and derailments due to misaligned sections. The fitter sections can be cut from standard straight pieces by clamping the rails in a vise and cutting to length with a hacksaw - or a motor tool with cutoff disks can be used (always wear eye protection when using cutoff disks). One 6" and two 2-1/4" fitters are required.

The tendency of the track to work itself loose was especially frustrating in the area behind the Christmas tree, as it is difficult to get back there to correct the situation, especially when there are presents under the tree. Make sure all these rail-joints are very tight, and if possible, use clips or wraps of tape around the ties to provide extra strength in keeping these sections together. Even screwing the sections to pieces of scrap plywood would be less trouble than continually having to rejoin track in the corner. Of course, using fitters to establish correct geometry will reduce the stress on these pieces, but a floor layout still gets a lot of movement and strain that can work track loose, especially when dogs or children are present.

Be sure you have adequate clearance between the track and the walls and furniture. I used some spacers of scrap material between the rail and the baseboard at several places to keep the track from working its way closer to the wall.

To see a wiring diagram of the layout, click on the transformer.

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