Dealing with trackwork imperfections/derailments? I am at a loss


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k4kfh

Member
Hello all,

I have a 5'x9' HO scale layout that uses Atlas track. It is a modified version of the Great Eastern Trunk plan, with a railyard added along the front edge. I have a turnout that comes off of a curve on a hill (constant grade where the turnout is) that is giving me nothing but problems.

Most of my problems are only with my Bachmann 2-8-2 Mikado, which is the largest wheelbase locomotive I have. It likes to find small hills/bumps in the track and lift its front drive wheel over the rail, causing a massive series of shorts and derailments as it bounces across turnouts.

What have you guys done to combat small track imperfections like this? I have tried shimming with styrene, but it never seems to work. Any tips?
 
Does the diverging track continue on at the same grade, or does it begin to level out, drop, or rise from that point onwards?
 
Step back and take a deep breath. First, does this engine derail elsewhere? What makes you suspect that the turnout is the problem rather than the engine itself. Do other engines/freight cars have the same problem at the same place? That being said, turnout frogs on some Atlas turnouts can be high and need to be filed down a bit. I find it to be a problem on #6's more than #4's. You didn't mention which size you were using. You also didn't mention whether it occurred on the straight or diverging route. A 2-8-2 is going to have trouble on a diverging route of a #4 no matter what you do. Have you checked the gauge all of the way through the turnout yet? If you really suspect that the turnout is at fault, there may be no choice but to replace it. I really think that the combination of downhill turnout on a curve with the long wheelbase steamer may be more of a factor than the turnout itself.
Just my thoughts.
Willie
 
k4kfh said:
What have you guys done to combat small track imperfections like this? I have tried shimming with styrene, but it never seems to work. Any tips?
Click to expand...
If the possibility of the locomotive's wheels are out of gauge or not tracking well has already been taken care of, Atlas custom line turnouts like to bow causing the frog to be higher or lower than the rest of the turnout. Check to see if the turnout in question is bowing up, and if so a properly place nail should make it go flat. If it is bowing down, (you didn't say where you had tried shimming) put a shim under the frog.

Neither did you relate whether it is going astray on the points or at the frog. If the points are pointing (ha ha) up hill, remember a train coming down is going to be slamming against the outside of the curve, check that the track gauge is not to narrow at that point, and not to narrow through the turnout.
 
Thanks for chiming in IH. At the time that I posted, checking the wheel gauge of the loco didn't occur to me, since that is the first thing I check when I get a new loco.
Willie
 
I recently purchased a couple new locos. One wanted to derail where nothing else has. One spot was just past a turnout going downhill. I had to shim the outside track up a little, that is, the outside of the curve.

Another spot was just before a turnout, at the end of a curve. Again, I had to shim the outside track up a little. I use a sliver from a toothpick. I sharpen the toothpick and slide it under the ties, then snap the rest of the toothpick off so it doesn't show.

Just in case you experience this situation somewhere. It was an easy fix. My track is ballasted down and so it stays in place either side of the shim.
 
Iron Horseman said:
If the possibility of the locomotive's wheels are out of gauge or not tracking well has already been taken care of, Atlas custom line turnouts like to bow causing the frog to be higher or lower than the rest of the turnout. Check to see if the turnout in question is bowing up, and if so a properly place nail should make it go flat. If it is bowing down, (you didn't say where you had tried shimming) put a shim under the frog.

Neither did you relate whether it is going astray on the points or at the frog. If the points are pointing (ha ha) up hill, remember a train coming down is going to be slamming against the outside of the curve, check that the track gauge is not to narrow at that point, and not to narrow through the turnout.
Click to expand...
Is there any good way to check wheel gauge without a tool? I can order a tool, but if there's a "poor man's wheel gauge" trick I'd rather do that.
 
logandsawman said:
I recently purchased a couple new locos. One wanted to derail where nothing else has. One spot was just past a turnout going downhill. I had to shim the outside track up a little, that is, the outside of the curve.

Another spot was just before a turnout, at the end of a curve. Again, I had to shim the outside track up a little. I use a sliver from a toothpick. I sharpen the toothpick and slide it under the ties, then snap the rest of the toothpick off so it doesn't show.

Just in case you experience this situation somewhere. It was an easy fix. My track is ballasted down and so it stays in place either side of the shim.
Click to expand...
When you say you sharpen the toothpick and slide it under the ties, you mean from the side of the track (parallel to the ties) right?
 
Okay, awesome. I was looking at the one from Micro-Mark, is that a good one? Is there a better one or is that what I want?

Sent from my SAMSUNG-SGH-I337 using Tapatalk
 
Long driver wheelbases do not like to have roll near any of the three exits of a turnout. There is no problem with having a turnout on a grade just as there is no problem with a bridge or a level crossing on a grade. In fact, they're all pretty much on a grade, even if a small fraction of a percent. If your loco's frame has rolled even 1.5 mm as it nears the frog, the leading axles, or even the entire engine truck, might be lifted enough that it is light and the flanges on the wheels will lift out of the gauge. However, those trucks are mounted purposefully sloppily so that they don't do that. So what happens next is that the leading set of drivers experiences the same thing. This is especially true if the curved closure rail sags the least bit, or if it's joined point rail rolls a bit on a sloppy hinge, or if that point rail is not supported by all the ties and IT sags. Someone mentioned a high frog bearing surface, and I have heard that some metal frogs need to be pressed down a fraction into their plastic pads...this is for Atlas turnouts. You have to heat the frog rails until the plastic softens and then you place a straightedge across the frog and its rails on either side and press down gently until they are all at the same height.

Yes, wheel gauges are important. So is the gauge between the guards and the stock rails and the wing guards near the frog and the frog point. THAT's why you must have...MUST HAVE...an NMRA track gauge for your scale. I couldn't begin to tell you how useful that thing is.

Get strong light behind the engine and in front of it. Direct bright light. Use an Opti-Visor and run the loco through the derailment spot back and forth. Watch for an axle lifting, or watch for a wheel flange working its way across the rail bearing surface.

Place a straight edge over the entire turnout. Go buy one the right length if what you have is too long. Get down and look between the rails and the straight edge. If you see a hill or a sag, that's probably where your trouble lies.

Sometimes the points need to be sharpened, or their joint tightened so one or both don't roll over under the engine's weight...thus widening the gauge there. Or, they don't like snugly against their stock rails and they get picked. Or, as I said previously, one or both is not supported, especially the curved one, and one or more flanges lifts out of the gauge there.

It's not easy, usually, and not quick, but you'll eventually spot the problem. Repeat trials in both directions until the cure becomes obvious.
 
k4kfh said:
Okay, awesome. I was looking at the one from Micro-Mark, is that a good one? Is there a better one or is that what I want?

Sent from my SAMSUNG-SGH-I337 using Tapatalk
Click to expand...

That one should be just fine, assuming you're looking at the NMRA standards gauge, like this one: http://www.micromark.com/NMRA-Gage-HO-Scale,7530.html

It's really nothing but a piece of sheet metal, but it's one cut to very precise dimensions and shapes. There are no moving parts and they're a reputable company, so it should be sturdy enough to work well.
 
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