Storing Rail


As I’ve mentioned previously, I’m going to be hand-building turnouts for the new layout, and possibly also hand-laying some of the track, although I’ll mostly use flex-track. But this means that I need to buy bulk rail. I’ve actually done this in the past, and one of the problems I’d had was that rail is easily bent. And once bent, it’s generally not usable. I needed a place to store rail where it could be kept straight. And I was likely to have more than one rail type or size, so I also needed a means to keep the different kinds separate.

A friend suggested PVC pipe, which turned out to be a very good idea. A quick trip to the local hardware super-store revealed that 3/4” PVC pipe looked like a good size for storing a bundle of rail, and it comes in ten-foot lengths, which evenly subdivides into 40” lengths that will hold either 36” or one-meter (39.37”) lengths of rail. The store would even cut it for me. A solid cap on one end, and a threaded fitting on the other with a screw-on cap completed the design. I’ll probably eventually build a wood frame or rack to hold several of these tubes on a shelf or wall.

If I were hand-laying track and buying in large quantities, I’d probably use larger diameter pipes to store it. But for keeping a dozen or so rail lengths on hand for turnout assembly, this is a good size, and it limits the amount of motion the rail can have. I could have left one end open, but having a cap means I can carry the pipe around with rail in it. For example, I expect I’ll take these to the store when I buy rail, and transport it home in them, to avoid any risk of in-transit damage.

Note: like many things in the construction industry, pipe dimensions are misleading. A 3/4” pipe per “schedule 40” (what I bought) has an outside diameter just over an inch, and an inside diameter of 0.824” (20.9 mm). If you buy schedule 80 pipe (which apparently is gray rather than white) in the same size, the inner diameter is 0.742” (18.8 mm). Those inner dimensions are also “typical”, and I’ve seen other numbers listed for them. Finally, there are also some specialty types with other dimensions, but these are the two common forms. The exact diameter doesn’t really matter, but more is better for a storage container, so I recommend the white pipe.

Detail of end with pipe fitting

Gluing them was straightforward, but used a MEK (Methyl Ethyl Ketone) cement (technically a solvent, like ordinary plastic glue) that contained acetone, among other things. Very nasty stuff. I did it in a friend’s garage, with the window left open, using a “low VOC” formula, and even the next morning the odor was still strong. By 24 hours the odor was mostly gone. For a more detailed description of gluing PVC, there’s a good Instructable here.

Ideally you should clean and prime the PVC before applying glue, but since I don’t care about maximal structural strength or being water-proof, I just wiped dust off the pipe and applied the cement directly to both parts where they would touch. Work on one part at a time, and work quickly: you only have about 20 seconds after application before it dries (less in hot or dry weather). If there’s any force pulling the parts away from each other, hold in place for 30 seconds until it sets. The base cure time is 2 hours, so I did one end of each pipe and came back two hours later to do the other ends, so any fumbling about wouldn’t dislodge the first part.

MEK, as mentioned, is nasty stuff (see my Material Safety page for more info). You don’t want it on your skin, so wear disposable nitrile gloves. And even the fumes are considered to be carcinogenic, so you don’t want to breathe them. Use it outdoors or in some place where the fumes won’t get into the house (a shed or garage) and leave it to cure. And keep it away from anyone pregnant. And, of course, don’t eat, drink, or smoke while using it. Particularly the latter, as it’s highly flammable. Very nasty stuff.

Although cure time on the jar is listed as “2 hours”, it actually varies by the size of the joint. You can find cure-time charts by searching online. The one for my brand of glue noted that for a joint my size, at 20° to 40° C, typical cure time was 6 hours, but a full (180 psi) cure took 36 hours. These increase with humidity above 60%. I left the finished parts in the garage for a couple of days so they wouldn’t smell up my train room.

I may paint these, either to color-code different types of rail, or simply to make the shop look nice. Painting PVC is fairly straightforward, simply clean it with window-cleaner (anything with ammonia), sand lightly with 220 grit sandpaper to give it “tooth” for the paint to grip, then wipe any dust off with a damp cloth. Finally, spray it with a plastic-compatible paint. I’d probably use spray cans, as these won’t fit in my airbrush spray booth.

Multiple coats will likely be needed for a solid finish, and these need to be applied after the paint has partially dried, but not before it sets (somewhere between 30 seconds and 5 minutes is probably good). Otherwise you need to wait a week or so to recoat to avoid crazing (cracks in the paint finish). Times will vary by brand.

Pro-tip: when painting, leave the cap off (you don’t want it painted on), wrap masking tape on the threads so you don’t gum them up, and stick a dowel inside the tube to use as a handle so you can paint the whole thing. I’m still working on what I’d use to hold the dowel while the paint dries. Maybe a board with holes drilled in it.

The parts cost excluding glue was US$10.20, and the glue sells for about US$5 for an 8 oz jar (good for about 275 joints; far more than I will ever need). So for about US$5 each, and about ten minutes of work, I now have three one-meter rail storage tubes. I expect I’ll make more of these.

Planning a Test Track

I’ve been thinking about this for about two years now, but it’s finally made it to the head of my “things to do” list: I want to build a short test track using the techniques I plan to use for the new layout: code 55 flex track and turnouts made using the Fast Tracks soldering jigs.

There are several reasons for this: first, I want to refresh my flex-track skills. Second, I want to learn how to use the jigs to make turnouts. Third, I want a fairly complex interlocking where I can try out electronics for detecting trains and controlling signals and interlocking those with turnouts, as well as interfacing all of that to DCC and JMRI running on a computer. And finally, I need to test some trains and see if they have any issues with this type of track.

So the first order of business was to figure out what I want the interlocking to look like. I started by sketching out an interlocking with a couple of tracks and some sidings, which was a nice, generic, interlocking, but not really representative of what I want to model. I’m modeling high-density urban commuter passenger lines in Tōkyō, and those are double-track with few sidings.

So that turned my thoughts to the junction between the Chūō Line and Sōbu Line at Ochanomizu Station, and the set of interlockings just to the west of there, between Ochanomizu and Suidōbashi stations. I’ve done a lot of research on that area, and know the layout of the track and associated signals fairly well. It has a mix of 3, 4 and 5-lamp signal heads, so I can test most and maybe all of the signal types I’d use. Plus it’s a very complex environment, which makes for a good test.

Unitrack Update

While I’m now planning a layout based on flex-track, I’m still interested in Unitrack. However, when a new announcement caught my eye, I realized that I’d missed some announcements late last year also, and thought I should bring my pages up to date, and do a Musing to summarize the new items. I haven’t bought any of these, and probably won’t, so I don’t have pictures to post. Some of this may be old news to readers who pay closer attention to Kato than I have of late, as several items are from last fall.

A Quiet Year

As you can see, I’m hard at work…

You may have noticed that things have been a bit quiet here this year, or at least the last half-year. I noted back at the beginning of the year that I had several projects I planned to work on. These were microprocessor-based systems for the planned layout. Those projects all stalled out for one reason or another. Not abandoned, but I ran into problems I couldn’t easily solve, and set them aside for other things, not all related to the railroad. One of them was a software project unrelated to the layout that ate all my spare time this fall. If I can get any of my railroad projects actually advanced next year, I’ll report on them.

I am still planning a “new” Sumida Crossing that’s more directly based on real-world urban Tōkyō. I have lots of ideas for what I want there, but it’s centered on JR East in the vicinity of the Sumida River. Which, honestly, doesn’t really narrow the scope all that much.

Simple Structure Lighting

It’s been a REALLY long time since my last post, since I got caught up in several other things after I started this review. I also planned to do more real-world testing with the lighting system reviewed here. I haven’t found time for that either, but I kept procrastinating on posting hoping I’d find a spare weekend. I didn’t. So I’m going to post what I have, and I expect I’ll eventually do a follow-up when I’ve had a chance to light a couple of buildings.

Woodland Scenics came out with their Just Plug building lighting system a couple of years ago, and I’ve been meaning to take a look at it, and see how useful it would be ever since. On the surface, it appears to be a dead-simple plug-and-play method of lighting buildings that you can power off any low-voltage AC or DC supply, such as the AC accessory outputs on a DC power pack or a simple “wall wart” power adapter. And it is.

It’s not cheap. A pair of stick-on LED lights with wires sell for US$10, the basic hub goes for US$17 without lights, and the expansion unit for a similar cost, and they’ll happily sell you a 1 Amp power supply for US$20 (about three times what you’d pay from a good electronics shop). A large system, with two expansion hubs, eight light hubs, and 32 lights would cost about US$348, or US$10.88 per light (with power supply). You could build the same thing yourself for less than a tenth of the cost. Except for two things.

Learning XTrackCAD

Today's post is about my latest (and more successful) attempt to learn to use XTrackCAD for layout design (see diagram above). I've made a few half-hearted attempts in the past, but was always turned off by the amount of up-front work needed to learn the dang thing. It's not at all obvious, at least not to me. This time I started knowing it was going to be a pain, but with the commitment to see that through.

Much of what I learned was basic, but some of it was very specific to what I'm doing, which is a flex track layout in Japanese N scale. If you weren't already aware, Japanese N is 1:150 scale rather than the usual 1:160 used in American/European N, and, oddly, for Japanese Shinkansen models, but I'm modeling normal trains for the most part. And I'm also planning to hand-lay at least some turnouts using the Fast Tracks jigs, although that turned out to be a lot simpler to design in XTrackCAD than I'd expected.

Memory and the Arduino

It's been a while since my last post, as I've been deep in a programming project and not working on anything else. It's model railroad-related, and I’ve written a lot of code, but as yet it doesn’t actually do anything and there's nothing really interesting to say about it. I’ll write about it when I actually have it doing something. Maybe next month.

But, as is usual for me, along the way I've tripped over a few of my own misconceptions, and learned a number of useful things. One of the latter is that I now know a heck of a lot more than I really wanted to about Arduino memory use, and in particular about how that changes in the Cortex ARM M0+. Since this version of the Arduino doesn't seem to be well-documented online yet, I thought I'd write up some notes about what I’d learned. This is fairly off-topic for a model railroading blog, but since a lot of what I'm doing these days relates to model railroad control and signaling systems using the Arduino and other microprocessors, it's not entirely off-topic.

And if you skip to the end, you'll find a useful function if you're programming one of these.

Arduino Knobs

This is one of those “interim posts” I mentioned at the beginning of the year, posts where I don’t have something yet in a state where I can really talk about it, so I focus in on one detail that’s been taking a lot of my time, as a form of update. But today’s topic, rotary controls for computer-based systems, is a generally useful one, so I don’t think you’ll count this post a waste of time. At least not if you are interested in this aspect of the hobby.

A rotary control, or knob, is a control that can select a continuous range of states arranged in a circle, such as the volume knob on a stereo. Any rotary control can also be laid out as a linear one, simply by straightening out the underlying mechanism (they have to be designed that way, but often are). In schematic diagrams, a linear symbol is typically used to describe either kind, since from an electrical perspective they are identical.

In model railroading the most common application for this kind of control is a throttle. My first power pack, an ultra-cheap kit pack from Tyco, had a linear control (actually it was rotary inside the box, but the lever sticking out the side looked linear to me). Later, my first good DC power pack (my MRC 501, which you can see on my Power Pack Testing page) used a knob, albeit a simple one.

But today, I need a continuously variable control for a digital system, an Arduino to be specific. And yes, it’s for a throttle, but I’m not going to talk about the actual project I’m working on, as it’s still in the early design stages and there’s nothing much to say yet. Instead, I’m going to talk about the various options for this one control, and then go into more detail about the one I’m using, seen in the photo above attached to an AdaFruit Feather M0 Proto (a type of Arduino) for testing.