Complex Interactions of Wheel and Rail

Broadway_closeup_906Another fall show season has come and gone so quickly! After spearheading the 12-table T-Trak layout at the Syracuse show, I helped with smaller layouts at Batavia, The TTCS Eagle show, and the Rochester Mini Maker Faire, before coordinating a 4-table T-Trak layout at the RIT show. No two layouts were alike; modular layouts never are. Each had its challenges to be met. The Syracuse layout, in particular, presented several situations where mechanical issues required finessing, in order to keep trains on track, together, and rolling.

Dirty Car Wheels

We got most of the Syracuse layout assembled on Friday afternoon. A few remaining modules were attached first thing Saturday before we connected the electrical gear. About a half-hour before the show’s official opening, the railroad was ready to run. Much of the crew promptly scattered in search of deals, so I put a 16-car freight train on the outer line. It ran well, except for one Athearn covered hopper which kept derailing. This hopper is one I’ve had for several years. It had been in storage a while, but I’d had no prior problems with it, and another identical car in the train was performing just fine. Sure enough, I found enough crusty gray buildup on the wheel treads to make trouble. Once this was cleaned up, the problem was solved.

Dirty Locomotive Wheels

Pulling this first train were three of my go-to show engines: my Life-Like C-Liners. The lead unit kept uncoupling itself from the other two, something that these engines do not normally do at a show. There were a few lumpy spots in the track where the trouble kept occurring, so I tried adjusting the levelling screws on some modules, to no effect. Again, it turned out to be dirty wheels, not track or coupler problems. The engine was bucking just enough to put slack in the coupling and pop it open. Another wheel cleaning later, and solved.

Bent Track

One of the straight stretches in the layout had a set of passing-siding modules. Cars kept snagging at the facing-point turnout of these modules, but nowhere else. I camped out at the spot, throttle in hand, to watch a car intently as it rolled through and…there was a wheel already off before it reached the turnout. I didn’t have far to look to catch the underlying problem. The module immediately preceding the siding had very bent rail ends, likely caused by careless handling when removed from a previous layout. I couldn’t bend the rails back into perfect straightness again, but I notified the module’s owner, and with some careful bending, got them almost straight.

Bad Car Geometry

As the day progressed, I added more cars to the train, including some that have not had much run time. One was a Bowser model of an early cylindrical Centerflow covered hopper. This car had come with truck-mounted Rapido couplers, so I had replaced the trucks with Micro-Trains, which usually ensures trouble-free running. No so this time. The Centerflow hit a bumpy patch of straight track, laid over on its side, and took three other cars with it. One of them, a nearly-new Atlas tank, kept going, right over the edge, all the way to the floor. Ouch.

A quick check with my scale revealed that the car was below its NMRA weight recommendation. This is not unusual; most cars come light from the factory, and require some additional weight. What’s more, the end sills of the car body were low enough to rest on the coupler pockets, which prevent the truck from moving freely under the car on uneven track. This car is on my workbench now, awaiting corrective attention. (It should be noted that the prototype for this car was also notorious for tracking problems when first built. One of the Erie Lackawanna’s cars did a real-life version of the Big Drop, all the way to the bottom of the Genesee River gorge, back in  the early Sixties.)

Coupler Problems

I picked up all the pieces of the Atlas tank that I could find, and assessed the damage. One of the trucks was pretty much destroyed, and the sill was cracked. With a borrowed bottle of plastic solvent, and a package of Micro-Trains trucks purchased from a vendor I know, I had the car back on the rails by mid-afternoon, but it soon became involved in a series of break-in-twos. The coupler knuckle was hanging low, because the lid of the draft-gear box wasn’t properly snapped in place. I never thought to check the couplers when I opened the package. Micro-Trains products have such quality control that it’s generally not necessary. It took some fussing with the tweezers to get all the pieces, particularly the spring, back into position, and the box lid properly seated, but yet another problem was put to rest.

Bad Module Alignment

By and large, things ran well at Syracuse. I had the Broadway Limited out, all 17 cars of it, and it ran beautifully. I also took the basic 10-car set to Batavia, and it ran well there, too. When I got it out at the TTCS Eagle show, however, the lead truck on the GG-1 kept derailing. The modules where the problem occurred weren’t as smooth as I’d like, but the same locomotive had run over those same modules at two previous shows in the same month, without trouble. A sighting along the tracks, eyeball just above rail, showed a kink in the alignment, perhaps after being bumped by a spectator. A gentle nudge back into alignment ended that problem.

Wheel Gauge

By the time of the RIT show, I had gotten quite good at knowing where to look for trouble, and how to fix it. Most of the modules in the RIT layout had already been run at other shows, and I had weeded out the troublesome rolling stock from my show box. There hadn’t been much demand for use of the long inner DC-powered loop on Saturday, so for Sunday I brought my pair of Life-Like SD-7s to run. (Great engines, these things. They have an old-school plastic chassis, instead of the metal split frame that contemporary N scale is made with, but they run smoothly and pull well. I have no plans to put decoders in them, but I get them out every now and then for DC running at shows.) The two of them were on a medium-length freight train, and one particular truck of one particular engine kept derailing on one particular turnout, on a module that hadn’t seen use in a while. My initial suspicion was a turnout issue, but the gauge seemed to check out, and my effort to narrow a flangeway with a sliver of masking tape on the guardrail did not help. (I’ve done the masking tape/guardrail trick before, with astonishing results.)

An inspection of the locomotive after the show revealed the center wheelset of the offending truck was gauged just slightly narrower than its mates. Not enough, even, to fail the gauge check, but enough perhaps to lift the truck up at the guardrail and cause problems. Spreading the wheels by about 0.010″ was easy, but it might be a while before I get a chance to run the engine through that same module.

Constant Vigilance

I gleefully confess to having an obsession with troubleshooting. Yeah, it induces some anxiety up front, but pays off later when things stay working the way they’re supposed to. I’ve seen other hobbyists take the cross-your-fingers approach, and end up frustrated when problems don’t solve themselves.

Advertisements