Rails and Ties

Work continues on Marceline Shops. More track is being laid and we tackled the lead to the turntable, turntable pit, and the turntable crank and equipment. The turntable to reached off the lead track via what turned into a "wye" stub switch. Most of the switches around the roundhouse and yard in Marceline are planed to be stubs.

Stub switches where very common prior to 1870. Rather then the conventional set of tapered point blade, on a stub switch both the movable rails and the ends of the rails of the diverging routes have their ends cut off square. The rails leading up to a stub switch are not secured to the cross-ties for several feet, and the switch mechanism aligns the movable rails with the rails of one of the diverging routes. This is the part that actually moves, and the source of the slang "bend the iron" for throwing a switch, because you literally are bending the iron. Stub switches were more common in the very early days of railroads and could be found in 19th century yards and branch-lines.


Easy to lay and easy to operate, their disadvantage comes in that rail alignment across the gap is not positively enforced and they require some substantial flexibility in the rails (meaning lighter rails), or an extra joint at which they hinge. Therefore, these switches cannot be traversed at high speed or by heavy traffic and so are not suitable for main line use. A further disadvantage is that a stub switch being approached from the diverging route that is not connected by the points would result in a derailment. Stub switches are also almost impossible to throw in hot weather, when the rails expand and press against each other. It also doesn't take much in the way of misadjustment to put the whole train on the ground.

One advantage to stub switches is that they work better in the snow and ice. The sideways action of the point rails pushes snow to the side, instead of packing the snow between the points and the rail in a more modern design. They are also less prone to operator error than bladed switches, especially in more complex arrangements such as double slip and crossovers, in the sense that the routing was more obvious just by looking at the rails.

Ties, weathered and in place.

Construction of the switch is pretty strait forward. The track center-line is first established. Both main lead, and diverging. The ties are then cut to length and laid out by hand and measured by eye. Like the rest of the track-work, once the ties are in place, they are weathered using Micro-mark's Age-It.

The rail is cut using a Dremel cutting wheel. The best way to establish the geometry when hand-laying, is to lay the common rail first. We chose the right side common rail, as this was the main lead, while the left was to be the turntable lead. We didn't worry about the switch stubs just yet. Preferring to get the rails in place first. Once the common rail was laid down, the other rails could be gauged appropriately against it. The frog was made simply by cutting the rails and filing them down to points. Once spiked together, the points where soldered into one rail. Using the cutting wheel, the frog was isolated for electrical conductivity.

Almost ready for the stubs to be cut.

The final step, once all the rails where in place, was to cut the stub rails free. The ends of the solid rails where then soldered in place, and the stubs soldered to their throw-bar. A switchstand is then linked up to the throw-bar and anchored to the headblock tie. (The headblocks are the extra long ties that the very end of the movable points, be they stubs or blades, rest on. They also support the switchstand.) 

The switchstands I plan to use are all uprights with tall targets. The prototype for these are operated with a handle that is raised, moved, and dropped into a slot. The lever handle is slotted, and when the switch is set for either track, the slot fits over a staple projecting above the lever far enough to receive a padlock which locks the switch. Switchstands are Caboose Hobby up-rights. While they might be a bit over-scale, I've always had a love for switches that had working stands. It just feels more "railroady" to me to be able to throw a switch using the stand-lever. Over the course of my own railroading career, I've thrown countless, countless, switches of this sort. As well as the more ubiquitous ground throw with the weighted arm. But that's another story.

The next stage was the turntable, and turntable pit. I obtained an Atlas full deck turntable. The turntable, which is run via a handcrank located on the turntable frame, has a geneva movement that index locks table in exact position every time. Originally, I had thought to simply motorize the turntable crank and drop it in as a full-deck. Which, while commonly found in the north, where the full deck made sweeping snow out of a pit much easier, would be slightly out of place on my southern based layout. 

Upon seeing the turntable, some of my friends had other ideas. One of which, suggested that we yank the hand-crank and index system out completely and instead attempt to mount a motor from an MTH locomotive as well as a gearbox under the baseboard and turn the table mechanically. We removed the turntable deck, and mounted it higher in the pit to allow room for the table to turn. A rail and support ties where added in a ring shape in the pit and a hole was cut in the foam to allow the turntable to sit flush with the approach rails. 

One problem we've encountered with this arrangement is that we can't seem to find a rear reduction that will spin the table at a realistic speed. The MTH gearbox seems to want to twirl locomotives like a record player. Some tinkering will have to be done. 

More to come!