Proto48 · Track Plan · Trackwork

Crossing Over

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I’ve started in earnest on the St. George crossover in front of the station site. This was a last minute addition to the plan as I discussed in Changes to St. George. In my fertile imagination, St. George was once a through station before the 1938 floods took out a bridge up the line. Two through tracks crossing Main St. help give the impression that there was once more to St.George and the D&NE.

But now, the Main St. crossing is the end of track. The stub end of track 2 will come in handy while switching. A couple of cars can be parked there out of the way but not over the highway crossing. It’s a more interesting design than originally planned and any resemblance to Paul Larson’s Mineral Point scene (Dec ’59 MR) is strictly coincidental.

These are code 100 #7 turnouts. I’m using the beautiful P48 cast frogs and points from Right-O-Way. Since these turnouts are being laid in place rather than constructed in a jig, layout is critical. The frogs must be carefully located so the actual crossover track is aligned correctly. No jigs or jogs allowed.

First, both outer stock rails were tacked down as straight as possible. Then the exact center of the crossover was marked. Then the point of each frog was located. Soldering an extension rail to the diverging side of each frog casting makes it a lot easier to get the crossover track aligned and in gauge. Guide lines at a 1:7 angle help align everything.

The frogs are electrically isolated by insulated gaps all four ways. Since the D&NE is DCC, everything else is either red bus (front) or black bus (back). Easy really. I solder feeders onto the bottom of most every rail and thread them down through a predrilled hole in the track bed. Each frog gets a green wire that goes to the center pole of the routing switch on the turnout control. Helping to ensure they’ll be no power drop outs, traditional rail joiners are also soldered between rails. They’re disguised by splice plates.

Once the frogs were perfectly positioned, the point assemblies were completed. A 1/4″ hole was drilled through the roadbed under the throwbar for the actuator rod. For throw bars, I used O scale circuit board ties from Fast Tracks that I had on hand. They’re too wide so I ripped them down the middle using a motor tool cutting disk as a buzz saw. (I’ll get some HO ones next time.) Making sure to leave enough length to slide under the stock rail, two #68 holes were drilled 0.875″ apart for attaching the point bridles. This leaves a 0.080″ flangeway between the points and the stock rails. Another hole is centered between the first two for the actuator rod coming up from below. The points were attached to the throw bar with small brass pins passed through the bridles and soldered to the bottom of the throwbar. The copper on the throw bar was cut between the points (both sides) as I wire them hot.

With the points in place, the inner, curved stock rails and the closure rails were added. I’ll use Right-O-Way rail braces to detail the turnout; five to each stock rail and four more for each guard rail. No gauge plates on these old style turnouts. The guard rails will be formed from code 83 rail. (The smaller rail keeps them from being scuffed bright during track cleaning.) The pronounced bend is prototypical for turnouts on some of the B&M mogul branches of the time. I like them. Tons of splice bars will complete the track details.

These turnouts will be operated by Fast Tracks BullFrog controls through a choke cable brought out to the fascia. The BullFrogs have a built-in switch to route power to the frog in the correct polarity. The points and closure rails are wired to the same DCC polarity as their adjacent stock rail so continuity through the switch does not depend upon point contact.

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There is a lot of spiking in yet to do along with turnout details. I’ll be at that for some time. But now tracks 1 and 2 can be completed down to the French River bridges. There’s another switch for the public delivery track that is laid mostly over one of the bridges. A somewhat extended lead allows the points to sit on dry ground on the other side of the river. Prototypical? You bet!

 

 

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