Articles - Track: Scratchbuilt Rerailer
12/30/2017
It was the day after a weekend train show. The wheels of every engine and car run on the club layout are invariably dirty. I usually bring all of my cars, and at least two engines. This particular weekend I ran both my FA-2 and RS-1 engines. So, there I was, facing the not-so-fun task of putting each engine and car on the track, one by one, cleaning their wheels. Getting the wheels to go on the track is easier than it was in N-scale, but it is still not trivial in S-scale. For N- and HO-scale you can buy a re-railer, but not so for S-scale. So, I decided that my first task should be to just build a simple one. I've seen many versions used, including someone taking an HO-scale rerailer, splitting it down the middle, and gluing it back together with a styrene spacer to make it fit the S-scale track gauge. However, with a few bits of styrene, I decided it might be fun to just make my own. This photo shows my attempt in 2015.
Scratchbuilt Rerailer
The styrene version worked well, but I had made it a bit too short. I thought re-railing one truck at a time was sufficient, but it became unwieldy when I had a number of cars to put on the track for a subsequent show. However, building a longer one out of the "precious" styrene seemed a bit costly, so I decided to make one out of wood. I also re-examined how the wheels actually work on the rerailer, and realized that if I could just make some outside guides that touched the outside of the wheels, it would be sufficient. So, I made the one shown below, and made it long enough for my 40-foot S-scale cars. The version in the photo actually was already missing its heel; the one that I originally put on there was much sturdier, and it had grooves for the rails, so that the unit could sit sturdily on a section of straight track. I built this in 2016. I took it to a couple of shows, and it worked well. But, what I noticed was that if the cars were longer than 40 feet, or if their couplers still had the Kadee-style "automatic uncoupling" wire installed, they would catch on the track. This was because the approach angle was too steep. Another member of club tried it, but had no luck with it either.
Scratchbuilt Rerailer
So, here is my 2017 version. I made it 17 inches long, so that it can handle longer cars and engines. I also made the approach angle much shallower. The guidance strips (made from small pieces of stripwood glued to the base) were copied from the previous version. However, I made one change. The guidance strips are now perfectly straight for 3 inches, and in line with the outsides of the rails on the section of flextrack. I found that on the previous version, I could get the front wheel of the truck to line up, but the rear wheel could still be crooked, which then caused the re-rail attempt to fail. With this new version, the entire truck will be perfectly lined up before it exits the rerailer and hits the track.
Scratchbuilt Rerailer
External Reference:
This version of the rerailer took a bit more effort to build. Since I wanted to have a nice, long, shallow-angle approach to the track, I needed a way to cut a taper in a piece of wood. I used a section of leftover 2"x3" stud, after cutting it to 17 inches long. To cut the long taper, I needed to make a tapering jig first, since I didn't have one. This photo shows the jig built and ready to be used for the first time. See the link for the YouTube video that I used as my go-by; however, there are plenty of others out there. Since I don't plan on making legs for tables, I decided to make mine as simple as possible, i.e. "hard-wired".
Scratchbuilt Rerailer
I cut two pieces of 3/4" plywood to the same length and width. Clamping them together, I pre-drilled holes for a hinge, and then installed the hinge with screws. A block of wood was then screwed to the end of the "swinging" side, which will act as the push block when pushing the board to be cut through the table saw. After determining the desired angle (I followed the same concept as the gentleman in the video suggested), I screwed a block of wood to the top of the two pieces of plywood, thereby locking the angle in position. It was then just a matter of carefully cutting the shallow angle into the piece of wood.
Scratchbuilt Rerailer
I made sure to not get too sharp (i.e. thin) of a cut at the end of the board, because that would break off under normal usage. You can kind of make that out in this photo. Next, using the piece of flextrack as my guide, I set the table saw fence up such that I could cut a groove in the bottom side of the rerailer, so that it lines up with the rails on the flextrack. The kerf of the saw blade is just a bit wider than the tops of the rails, which is perfect. The grooves have to be run all the way under the rerailer. That way the rerailer sits sturdily on the track.
Scratchbuilt Rerailer
I did a bit of clean-up work, and then glued the two guide strips to the top of the rerailer. I used the outside of the grooves to line them up, but that turned out to be a bit too narrow, so I had to hand file a bit away from the inside of the guides, to effectively widen their spacing. That is largely dependent on what brand of wheels you use, since the guides guide the outside of the wheels.
Scratchbuilt Rerailer
As I stated above, the first section of the guide strips were perfectly straight. After that, I lightly bent the strips in an S-curve and widened them to the outer edges of the rerailer. I then glued them in place with wood glue and some weights to let the glue set. This S Scale American tank car has always been notoriously difficult to get on the track, especially at train shows with low-lighting conditions. It is trivial now with this new rerailer. I just put it on the rerailer near the top...
Scratchbuilt Rerailer
... and start sliding it down the ramp. The position of the trucks is now immaterial. Note how I had to put a piece of wood in front of the wheels, because the car actually runs down the ramp all by itself and perfect puts itself on the track automatically! But I wanted to take this intermediate photo.
Scratchbuilt Rerailer
As the car gets further down the ramp, the wheels of the lead truck are being guided to the straight section, so that both wheels are perfectly lined up.
Scratchbuilt Rerailer
Here you can see the outside of the wheels being guided. If you are using hi-rail wheels, your guides will have to be taller, but the same concept works; you want to guide the outside of the wheels, not the flanges. As the car makes its way further down the ramp, the flanges will fall into the grooves, which are lined up with the rails.
Scratchbuilt Rerailer
As the lead truck is on the track, the rear truck enters the straight section and is then also guided in the same manner.
Scratchbuilt Rerailer
A perfect re-rail. I need to do some more testing, but so far I have not yet had a single fail. Like I said, this car rolls very easily, so I can just put it on the rerailer near the top, and it just rolls right onto the piece of flextrack. I need to try this with my battery-powered locomotives! Anyway, if you are in need of a quick way to rail your cars or engines, consider building this simple unit yourself.
Scratchbuilt Rerailer
Update: Version 3a. As I continued to test more cars, things went well. But then I tried my engines. The S-Helper Service NW2 worked well. Then the American Models FA-2. Not so much. When I brought out the calipers, the problem was obvious. The locomotive's wheels are in gauge, but their wheel thread is 1/64" (one scale inch) wider than the ones on the freight cars. This caused the engine to bind against the two guide strips, and jump them. The next morning I thought that if I redesign the rerailer to have the guide strips such that they guide the backs of the wheels, then the width of the thread shouldn't matter. I might even be able to use Proto:64 wheels! So, I cut off about 3-1/2" from the outside guide strips (leaving the upper parts in place), and added inner strips using the same strip wood. I then made sure that they were glued centered across the grooves the rerailer had, and that they were spaced as per the S-scale NASG gauge, using the "Wheels" measurement.
Scratchbuilt Rerailer
Here's the new layout of the guidance strips. The first three inches are straight as the previous outside guide strips were, so that both wheels of a truck are straight by the time they hit the rails. In the photo, I still needed to sand away the glue-globs so that everything moved smoothly. The only downside with using the inner guide strips is that the American Models FA-2 truck mechanism is very low, so it might get stuck on the strips. However, if that happens, just pushing the engine along will work. Sanding down the guide strips a bit is another option.
Scratchbuilt Rerailer
I then went back and tested a number of cars and all of my engines, and there was not a single re-rail failure! In February 2018 I participated in the Houston S Gaugers' layout at the World's Greatest Hobby show here in Houston. We were very short on crew and we had electrical problems, so I was under a time crunch to get my battery-powered train up and running by opening time. Using this rerailer, I was able to get my FA-2 A-B-A and 20 cars plus a caboose set up in no time. The locomotives needed to be pushed through the rerailer, but the cars I could just place on the unit and let go. By the time I came back with the next car, the previous one was nicely railed on the track. Not a single misfire. This tool was a real time saver!

My article about building this re-railer can be found in the May 2018 issue of the NASG's the Dispatch magazine!
Scratchbuilt Rerailer