As regular Forum visitors are aware, I’m something of a fanatic about building derailment-resistant trackwork. So, imagine my chagrin when several cars I had just purchased derailed when being backed over switchwork that had been in trouble-free (until yesterday) service for almost two years.[:O]
Several test runs, in both directions, convinced me that the extremely underweight 4-bay hoppers (intended for kitbashing) would derail at the butt end of one particular switchpoint, on facing point moves only.[|(] When I finally got up close and personal with a bright work light, I noticed that there was a tiny blob of solder on the railhead - left behind when that point was soldered to its pivot pin. [#oops] It couldn’t have been more than .01" high - just enough to bounce the flange and lift it onto the top of the curved closure rail.[:(!]
A few seconds of attention with a fine-cut file restored the proper railhead contour. Now those four-axled feathers seem to roll through without a hitch.[tup] The next step will be to push the whole string over all of the in-service specialwork to check for other potential problems.[B)]
The moral of the story? Just because you haven’t had a problem, don’t think everything is perfect. Murphy is alive and well![}:)]
Chuck good to hear a molder as advances as your self have problems, make me feel a little better. My new section is the best laid track to date. 24 inch turns, number 6 and 8 turn outs. Big Boy Loves it, same with Y6b, AC 6000, dash 9, Sd 50’s, E-6 and E-7’s. Tonight I ran one of my BL2’s on it, it makes a bumping sound on two of the turn outs, does not derail just bump? Odd thing is I was runnig on the main bench that is not as well done, same sizes turnouts, not a bump to be heard?
Sounds like the natural play in the drivers is allowing it to shift side to side and the “bump” you’re hearing is the drivers getting to the limit of their tolerance. Either that, or your locomotive is experiencing the natural pressure pushing it to the outside of a curve and hearing it rebound back as it pushes itself through.
Say WHAT??? The problem children are FOUR-BAY HOPPERS. The locomotives are nowhere near their tolerances - 610mm curve radius (eased) versus a ‘maximum-minimum’ tolerable radius of 450mm or less (without easements.)
I have other, longer, bogie stock, cars that have been traversing the same turnout curve with ease for two years - but those cars are ballasted to NMRA recommended weight and have far better quality trucks.
Since I started this thread I’ve run those (fillintheblanks) over the entire railroad (or at least the part that’s finished) and identified two problem cars (flash on the truck mounting pads) and one other track problem (solder too high in a flangeway.) I’ve also loaded them with drywall screws - and eliminated their tendency to fly.
I hear you loud and clear. My layout is in a partially uninsulated garage (“California Basement”) and like you, I’ve had to be EXTREMELY careful in my track-laying–in my case to overcome some extremes of temperature between seasons. I like to think that I’ve done it all and done it well, but Murphy creeps up occasionally, and I end up having to ‘temper’ some sections that I ordinarily wouldn’t think of working. Oddly enough, never because of my locomotives, but because some piece of rolling stock suddenly decides it doesn’t like a particular track-joint. And when I look at the joint, it might be, like you, just a sliver of solder or a tweak where the rails join. For instance, I had an Intermountain PFE reefer that just refused to go over a certain piece of track without derailing. I checked everything until I was bleary in the eyes. Turned out it was not a wheelset out of gauge or an underweighted car, but the particular way the truck was balanced when it hit the joint. A few gentle swipes of a file to the track joint and tuning the truck-frame balance up a little cured it.
But if Murphy is invited, he’ll sure show up, LOL! [:-^]
Chuck, my first thought is that the cars-in-question didn’t have all-metal wheel sets and the cars are under-weight. Solving those issues, those cars may be OK. (By the way, did central Japan have four-bay hoppers? I’m totally ignorant about that.)
Mark, in his post earlier, Chuck mentions that he filled the two problem hoppers with drywall screws, so he seems to be aware that “tonnage” added will do the trick. [:D] I have resorted to the same with hoppers that don’t seem to want to behave…I add weight to them and they usually settle down.
Right on both counts! The big culprit is the lack of weight. The wheels may be plastic, but the cars will roll if you breathe in their general direction (I thought that track was LEVEL!!!)
Actually, these cars are kitbash fodder - destined to become (after major surgery) seven-axle articulated cars with one bay per carbody. Nothing like that ever ran in Japan, but the Tomikawa Tani Tetsudo has them.
Chuck (Modeling Central Japan in September, 1964 - with tongue in cheek)
As regular Forum visitors are aware, I’m something of a fanatic about building derailment-resistant trackwork. So, imagine my chagrin when several cars I had just purchased derailed when being backed over switchwork that had been in trouble-free (until yesterday) service for almost two years.
Several test runs, in both directions, convinced me that the extremely underweight 4-bay hoppers (intended for kitbashing) would derail at the butt end of one particular switchpoint, on facing point moves only. When I finally got up close and personal with a bright work light, I noticed that there was a tiny blob of solder on the railhead - left behind when that point was soldered to its pivot pin. It couldn’t have been more than .01" high - just enough to bounce the flange and lift it onto the top of the curved closure rail.
A few seconds of attention with a fine-cut file restored the proper railhead contour. Now those four-axled feathers seem to roll through without a hitch. The next step will be to push the whole string over all of the in-service specialwork to check for other potential problems.
First of all, that is THE BEST use of an icon EVER! In fact I am still laughing every time I look at it and imagine you doing the same look as those four hoppers hit the ground!
Secondly, thanks a ton for sharing this information. As a modeler who is just about to start laying track on a large layout for the first time, this type of information is very helpful to store away for future use.
I may have to keep a mirror in the basement so I can remember your post if I ever see [|(] staring back at me. Jamie
When I finally got up close and personal with a bright work light, I noticed that there was a tiny blob of solder on the railhead - left behind when that point was soldered to its pivot pin. 
It couldn’t have been more than .01" high - just enough to bounce the flange and lift it onto the top of the curved closure rail.
The next step will be to push the whole string over all of the in-service specialwork to check for other potential problems.