Looking east along the site of Santiago Yard, 1983.
Having built the roadbed and benchwork for Santiago, it’s time to build some turnouts.
CN number 7 turnout plan
When building this new version of the Midland Railway, I decided to use NMRA no. 6 turnouts for yards, and CN no. 7 turnouts wherever passenger equipment and/or large steam locomotives such as Mikadoes would traverse the diverging route. The odd industrial spur might use a number 5, but I’m limiting my use of those to where short cars and small steam loco’s might use them. A CN no. 7 turnout built in HO scale is not much longer than an NMRA no. 6, yet allows almost any model rail equipment to run through it.
Fast Tracks makes some nice assembly fixtures for NMRA number 5/6/7 turnouts, but not for a CN no. 7. The NMRA number 7 is a longer turnout than the CN version when built in HO scale. As I’ll be using a lot of the CN no. 7’s, I needed some device to help me build these in a consistent fashion and faster than laying them out using offsets and a scale ruler–every time. Here’s the diagram, taken from the CN turnout plan—
I converted the offsets from feet and inches on the CN plan to HO scale decimal measurements, and drew up a rough dimensioned drawing for a closure rail jig that fits between the gauge sides of the curved and straight closure rails. The left edge is where the tips of the switch points are located–
I was given some 2′ square 1/16″ thick aluminum signs a few years ago. I’d tried cutting a piece to make this closure rail jig using sheet metal shears, but found that I produced a piece of crumpled, distorted sheet metal which would not make a good closure rail form without lots of work flattening it. A little online research told me that when cutting sheet metal with shears, the smaller piece being cut takes the stress from the process, distorting it. Ah-ha! But if you use a jig saw and a metal cutting blade…
With a metal cutting blade in my old Sears Canada saber saw, I cut out an oversized blank. This process did not result in distortion, but a lot of swarf was produced by the blade. No big deal. This blank was then filed and sanded to produce a truly straight edge on one side. This edge became the edge that the gauge side of the straight closure rail is placed against.
I marked out the dimensions from my rough drawing on the aluminum sheet, using the straight edge for reference. I cut small slivers of aluminum off the sheet until I was near to the markings, leaving the part slightly oversize. This prevented distortion of the jig, as the cut-off slivers took the stress. I finished my cutting and shaping of this jig using a mill bastard file. Here’s the finished jig for setting and soldering to ties (or spiking them to wood ties) curved and straight closure rails for a CN no. 7 turnout in HO scale–
I white-glue a CN no. 7 turnout diagram to a scrap sheet of glass, then white-glue Fast Tracks’ PC board ties to the diagram. Here’s an example, with rails ready to be soldered to the ties–
I lay the frog in place first, measuring distance from frog to points and soldering the frog in place. I clean the tie tops off using a sanding stick, sand the base of the rails by drawing them over 400-grit sandpaper, and spread some rosin paste flux on the tie tops before soldering the rails to ties using regular 60/40 electrical solder.
This is followed by soldering the straight closure rail in place. I then bend the curved closure rail to almost conform to the jig, and solder it in place against the jig, as seen in the bottom turnout here–
The rest of the turnout is gauged off the soldered curved and straight closure rails, as well as those of the frog assembly. I use a three-point gauge to hold the rails as I solder them, checking my work afterwards using an NMRA Mark IV Standards gauge. I then run a set of trucks fitted with narrow-tread Code 88 wheels through it, looking for gauge issues, binding, or metal chips in the running surfaces of the turnout.
I soak the finished turnout in hot water to soften the white glue holding ties and diagram to the glass sheet. A scraper is used to gently separate the ties from the paper diagram, then the diagram from the glass sheet. Glue another diagram on the sheet, and the process begins again.
So far, so good. This use of a home-built jig-works well if you can’t buy a commercial turnout assembly fixture. 1/16″ thick aluminum sheet gives me a jig that will allow me to use Code 40 to 83 rail to build a turnout, using just this one jig. Left or right-handed versions of the CN no. 7 turnout are easy to build–just flip the jig over for right- or left-hand versions.
If Fast Tracks or Oak Hill makes a turnout assembly fixture for what you want. Buy it and use it. Don’t make your own closure rail jig. But if you want to model New York Central, Illinois Central, or even British Railways’ flat-bottom rail post-WWII turnout and have scale drawings for it, my method may work well for you.