gatrhumpy The problem areas are not where the switches or frogs are. They are around a 9" radius curve. Maybe I'll take apart the shell to see if any wires are disconnected. Thanks for the tip.
The problem areas are not where the switches or frogs are. They are around a 9" radius curve. Maybe I'll take apart the shell to see if any wires are disconnected. Thanks for the tip.
Before you start taking things apart, what is the minimum radius the manufacturer lists for this engine? 9 inch radius sounds pretty sharp for a 6 axle locomotive, even in N scale. I won't even ask what the overhang looks like on curves. Also, you may want to make sure the body of the loco isn't catching or riding up on some part of the surrounding terrain.
I had the same problem with a Kato HO scale SD-40 -- the electrical pickup from the trucks was through a bronze strip that ran the length of the locomotive on each side, and small protrusions on the trucks to transfer power to the strip.
This was a very poor arrangement electrically because flexing of the trucks would cause the truck to lose contact with the strip, and the locomotive would stall. I think Kato used this arrangement only on the SD-40 before realizing it didn't work.
The cure I found was to solder wire between the trucks and circuit board instead of relying on the strip.
I was running a consisted pair of Proto GP-9s (HO) when I noticed a similar problem. The lead engine was cutting out, and then restarting as the consist got a bit further down the track. I hadn't seen this behavior before, and pretty much everything is rock-solid on my trackwork. Next, I noticed that the engine cut out every time it entered a right turn.
I opened up the shell and found both wires from the decoder to the trucks on one side were disconnected. These are small wires soldered to connectors on the tops of the trucks, and they flex as the trucks rotate. I'd recently done some decoder work on that engine, and I probably weakened the solder joints while doing that. A few quick applications of the soldering iron fixed the problem.
You may have a similar problem inside your engine, perhaps on one truck only. Most of the time, power is still getting there from the other truck, but there are always dead spots on frogs, etc., so reduced pickup can cause problems like this.
It takes an iron man to play with a toy iron horse.
Ughhhhhhhhhhh. Well, I had to do a bit of surgery this past weekend. I tried to level the track, which was already glued to the roadbed, ballasted, and weathered. I tried to take some pliers and gently pull up on part of the track that dipped a little below the adjacent rail. This was causing my Atlas SD-35 to derail (but not the Kato SD-40, weirdly enough).
So I had to replace a section of 9" N scale track and a standard left-hand turnout. THAT was fun work. The SD-35 does not derail any more (at that spot), neither do the GP-60 and GP-38-2 I have. I ran the trains for about 45 minutes yesterday and no derailments anywhere on the layout (2.5' x 4').
I'm still having problems with the Kato intermitten stopping though at the same three spots on the layout. My short-term fix is to not use than engine for now.
I had determined that since the SD-40 is the longest engine I have, the trucks don't flex enough to pick up the minute deflections in the track, which is why it is stopping, because it is not picking up electricity. I will have to try to level the track somehow, hopefully this time without pulling the metal rails up!
gatrhumpy I have a Kato SD-40, and on certain spots of my layout, not matter on many times I clean the track and the wheels of the engine, it just stops if the voltage (i.e. speed) of the loco is low enough. I have a DC power pack (not DCC). I have narrowed it down to at those spots, the wheels engines, for whatever reason, don't make contact with the nickel-silver track (i.e there are lowpoints there). How do I bring up the track so it makes contact with the wheels of my engine? I only need to bring it up something like 1/2 a mm or so (I think). Coincidentally, my Proto N GP-60 works just fine around the track. This is on a 2.5 ft. x 4 ft. layout that can be transported, but has not been transported (or used) in about six months. I ran the trains and cleaned them, and expected some choppy performance, but I did not expect this. Should I try to use some needle-nose pliers and gently pull up on the track, being careful not to pull the track up from the ballast?
I have a Kato SD-40, and on certain spots of my layout, not matter on many times I clean the track and the wheels of the engine, it just stops if the voltage (i.e. speed) of the loco is low enough.
I have a DC power pack (not DCC).
I have narrowed it down to at those spots, the wheels engines, for whatever reason, don't make contact with the nickel-silver track (i.e there are lowpoints there). How do I bring up the track so it makes contact with the wheels of my engine? I only need to bring it up something like 1/2 a mm or so (I think).
Coincidentally, my Proto N GP-60 works just fine around the track.
This is on a 2.5 ft. x 4 ft. layout that can be transported, but has not been transported (or used) in about six months. I ran the trains and cleaned them, and expected some choppy performance, but I did not expect this. Should I try to use some needle-nose pliers and gently pull up on the track, being careful not to pull the track up from the ballast?
I use 3 fairly easy checks to make sure the trackwork is flawless (or as good as my 50+yoa hands can do). All of these came from Model Railroader or here in the forums.
Once the track is mechanically flawless, and you know wheels and inside corner of the rail are clean, it has to be electrical. Rail joiners lose their ability to maintain both electrical contact and mechanical alignment over time, with the electrical contact going first. This occurs because of the microscopic "working" of the track joints by the passage of trains over them, and by expansion and contraction of both the benchwork and the rails themselves due to humidity and temperature changes. In most cases, moisture absorbtion by wood will cause almost all the movement. Tightening rail joiners with pliers can temporarily fix things; replacing the problem rail joiners is better; and bypassing the rail joiners with jumpers or feeders is the permanent solution.
Finally, if the power pack is a rheostat type (cheapest and train set ones usually are), changes in current draw by the train for any reason causes changes in voltage supplied to the locomotive. If the load on the engine is suddenly increased for any reason - train entering a curve, starting a slight upgrade, etc - the voltage to the engine is automatically reduced by the rheostat without any action on your part. A transistor throttle (MRC Tech series, Bachmann Spectrum, etc, power packs) will maintain a much more stable voltage despite small load changes.
my thoughts, your choices
Fred W
Thanks for the reply. I already have two feeders on that loop of track, in fact, I have a feeder about 0.25 inches from where the engine stops. Hmmmmmm.
This sounds like a case of poor electrical wiring combined with loose rail joints. You may need to solder your rail joints and provide more power feed wires to the track.
Erik Fiske
I couldn't fix your brakes, so I made your horn louder