Originally Posted by Tom999999
As a newcomer to N scale (had an HO layout years ago). I went out and bought $ 400 of Atlas Code 80 track for a larger tabletop layout. Started laying track and the turnouts are a disaster – I get derailments about every third time the train goes through them. A couple of Bachman diesels and Bachman cars - nothing weird about them, so I assume it’s the turnout’s fault. You can actually see the cars jostling up and down and side to side as they go over the plastic parts of the turnout before they derail. A few questions and observations:
- The turnouts are all standard #4. Do other people have luck with #4’s or is it just me? Should I scrap my track plan and redo it with #6 or #8 turnouts? Would that help?
- Some of the turnouts work O.K. The problem seems to be mostly in the right turnouts – is it possible I just got a bad batch of right hand-turnouts?
- Should I cut my losses and scrap everything and go with another brand of track?
Unfortunately you are not the first, and won't be the last, to have serious problems with Atlas turnouts. They are at the low end of the quality scale.
That said, there are things you can do to make them work better. The advice you have already gotten is very good. I agree with MichaelE's suggestion that you may have gotten some turnouts that were downright defective. That's perfectly possible. However, I doubt Michael's suggestion that a frog, or guardrail, is too high. While anything is possible, frogs are usually too low on nearly all commercial turnouts, not too high. That doesn't mean it couldn't happen, just that it's unlikely.
Guard rails are typically either even with, or slightly below, the height of the running rails. Their flangeways though, are typically too deep, and too wide. I suspect that is more likely to be the cause of the problem than too high frogs, or guard rails, but I can't rule those possibilities out either. The straightedge test he recommended should tell if they actually are high, or not.
As CTValley recommends, you definitely should invest in an NMRA track/standards gauge. They only cost about $12 and you can order one at www.modeltrainstuff.com
With the gauge, you will be able to check about six different critical areas on the turnout, and fix any that need it. The same gauge will also let you measure the "gauge" of (distance between) each set of wheels, and also the flange depth of the wheels.
As bewhole says, some older N-scale cars, and locomotives, came with deep, oversize, wheel flanges which N-scale modelers nicknamed "pizza cutters." They are a problem on Atlas code 55 track, where they hit the oversize spikes Atlas uses on their code 55 track. However, even if you do have those, deep-flanged wheels, it shouldn't matter on your code 80 track and turnouts. The code 80 rails are high enough to work with either the older, deep-flanged, wheels, or the newer, shallow-flanged, type.
Most commercial turnouts come with flangeways that are both too wide, and too deep, to meet the specs in the NMRA gage.*
The excess width can cause derailments, and the excess depth lets wheels fall into the too-deep frog flangeway, and then be pulled back up when they hit the frog point. This may account for some of the "jostling up and down and side to side" your cars are doing. Adding weight, as CTValley suggested, might help, but setting everything, including the depth of the frog's floor, to meet the NMRA gauge's specs, will likely eliminate the actual cause of the jostling altogether.
More seriously, the wheels, or the turnout, or both, may be out-of-gauge, which can cause the wheels to climb up the rails and derail. These are two of many critical things you can check with aN NMRA gauge.
The file"Improving Atlas Turnouts" attached below, explains some of the problems inherent in the Atlas "Snap Track" turnouts. Some of the early pages are aimed at the HO-scale version which has a very tight (for HO) 18" radius curve built in. We N-scalers have a nice broad (for N) 19" radius curve so you can skip those first pages if you like. Starting on page 8, you will see photos showing how the NMRA gage is used to find problems and what you can do to correct them.These same problems and fixes apply to N-scale Atlas turnouts as well as the HO-scale ones.
While a number 4 turnout is a fairly sharp one, I don't think switching to # 6 or #8 turnouts is itself a direct fix. Somewhat coincidentally, it would work, but only because you would probably be buying a different brand of turnout, which was better made, not directly because of the change in frog# alone.
A larger frog# is still a good thing however. Some longer cars and locomotives may have trouble going through a #4 turnout. (Due to the much gentler curve in the Atlas N-scale turnouts, this is less likely on an N-scale Atlas turnout than on the HO-scale version, with it's sharp turn.) Micro Engineering's excellent turnouts, for example, only come in #6 right, and #6 left. If you were to switch to them, the biggest improvement would be the change to a better brand, not just the increase in frog number.
The file "All about turnouts" gives a lot of information on different brands of turnouts. If you decide it's not worth your time and effort to fix your Atlas turnouts, you other option would be to replace them with Peco, or Micro Engineering turnouts, both of which are much better quality than Atlas, and work reliably right out of the box. (The only thing I have ever had to fix on a Micro Engineering turnout was to slightly widen the guard rail flangeways to match the NMRA gauge. This only took a minute, and the turnout has worked flawlessly ever since.)
The downside of course is the high cost of "cutting your losses" and having to pay for the new, better quality, turnouts.
That's up to you, but I agree with CTValley's suggestion that you try fixing (at least one of) your problematic Atlas turnouts before investing a lot more money in replacing all of them. You may find that the fixes aren't all that hard, and they will certainly save you some money.
By the way, Atlas "Snap Switch" turnouts have a unique geometry. No other brand, or even Atlas's own "Custom Line" ** turnouts, will be an exact fit. You will need to remove some track near each turnout and install short pieces of flex track. That's easy enough to do, but it may be a factor in your "fix, or replace" decision.
*So why do commercial turnouts come with flangeways that are too wide and too deep? My guess, (and it's only that) is that the manufacturers want to accommodate slightly out-of-gauge wheels, and deep flanges. That makes things sloppy. I build my own N-scale turnouts with frogs that meet NMRA standards for flangeway width and depth. This makes for very smooth, reliable, tracking through the turnouts.
** I don't think Atlas offers custom line turnouts in N-scale. It is an option in HO-scale though.
Improving Atlas turnouts pdf version.pdf
All AboutTurnouts rev 4.pdf
How I scratch build turnouts new(8).pdf