I don't remember seeing one before. Anyhow I took some pictures Saturday. The picture to the left is looking north through the turntable and the right one is looking south. The right one was taken about at the yellow X at the left upper edge of the left photo.



This next pictures take farther to the right are maybe easier to understand.

The setup is quite interesting. On the turntable, the narrow gauge equipment rides on the center two rails while the standard gauge equipment rides on the outer two. However, on the ground, the narrow gauge and the standard gauge share a common rail, thus necessitating the narrow gauge points to allow the narrow gauge equipment to go from a shared-rail setup on the ground to the separate-rails setup on the turntable.

Also, the switch shown in the photo is only for narrow gauge equipment. One narrow gauge track branches off by itself while the other continues to share the right-of-way with the standard gauge track.

If I remember correctly, some standard gauge locomotives had offset couplers so they could switch narrow gauge equipment, but it looks like that couldn't be done with this setup.

It does make me wonder, though, if derailments due to mis-aligned switches were more common in dual-gauge yards. It must have taken a special breed of railroader to be able to glance at a dual gauge switch and know that everything was set correctly.

The Colorado Railroad Museum also has a turntable from the CB&Q that is dual gauged in exactly the same manner. It is a "modern" girder type table with an Armstrong power system.

The arrangement of tracks were you go from 3 rail to 4 rail is called a "draw". The D&RGW turntable in Chama was also a 4 rail table.

Instead of Chama (deep in narrow gauge country) do you mean Alamosa (where the gauges met)? Or there was a period of time when Durango had dual gauge trackage because the Farminton branch was built standard gauge.

As I recall, the record is probably held by the turntable in the Brookville Equipment factory. It has 4 gauges, all centered. It serves 2 tracks in the erecting shop, the paint shop track, a couple of storage tracks, and the interchange track (standard gauge only). The whole factory has no switches!

The California State Railroad Museum in Sacramento also has a 4-rail dual gauge turntable with a draw on one of the tracks leading away from the turntable.