I have seven Atlas code 83 Snap Switch turnouts (item no. 542, basically a #4) on my layout, all powered by Tortoises. They've been but moderately used for only about four years now. Over the past few months, three of the turnouts have begun misbehaving by derailing all my locos (four diesels and one steam) on nearly every occasion - but only when entering the diverging route. When switched to the mainline route - or when the locos are exiting the diverging route - they operate perfectly and cause no derailments. A fourth turnout, strangely enough, derails the locos about 10% of the time when they are exiting from an adjoining mainline track. But perhaps that's another story.
I've checked everywhere there is to check on the turnouts, the adjoining trackage (also Atlas code 83 snap track and flextrack) and the locos' wheels and trucks with the NMRA gauge. All appear to be properly and proportionally adjusted. I also see no kinks or other track or loco anomalies.
A close eyeball inspection of the problematic turnouts, however, shows that both trucks of the locos jump in the same two places on the outside point rail (again, only when entering the diverging track): first, one tie beyond the throwbar and again exactly half way across the point rail. That one outside point rail is also not precisely aligned at the pivot point with its other half (as is the inside point rail); it leans inwards just a tad and wiggles slightly at the touch of a finger - and it has a slight, but visible, bend along its entire length. The inside point rail is perfectly straight and firmly in place. Additionally, the ends of both point rails (which are sharp and not at all blunted) long ago worked themselves loose from the throwbar. I used to push them gently back in until they "clicked" in place in the throwbar, but they'd always pop out again. More recently, I used CA to secure them in place, a remedy that seems to have worked. Mostly.
All this tells me there's simply a quality issue with the design and manufacture of Atlas turnouts. I even replaced one problematic turnout with a brand new, identical one last week, only to find that the locos continue to jump at the same two places on the same point rail and immediately derail. Rarely will the locos continue ahead, but always with an audible "complaint" before re-righting themselves on the track. The new turnout also has the same point rail misalignment and wiggling issues as the older one (you'd think developing such a problem would take time!). Oddly, both turnouts also have a noticeable vertical bend in the middle, which according to a review on the M.B. Klein site I recently read, is a chronic problem with Atlas turnouts.
Given all this, is there a way I can fix and eliminate this problem for good? Am I missing something? Or, as I'm starting to think, should I dump Atlas turnouts and go with a better quality make? I'm thinking Peco, Walthers or Micro Engineering. Are there any compatibility issues with those three makes and Atlas tracks? Building new turnouts by hand is not something I wish to get into, however. So it's either fix or replace.
I look forward to reading your potential fixes and recommendations on quality of design, build and operation of other brands.
Kerry
Kerry,
If these have been working for 4 years, I doubt if this is a design or manufacturing issue. Has you benchwork shrunk with the low winter humidity? I have 62 Atlas Customline code 83 turnouts and have had little issues. Since you have Snap-Switch turnouts, they are not #4 turnouts, they have a continuous radius curve on the divirging leg. These will be tight with modern 6 axle diesels and medium or larger steam - But you should be able to run them slow through this tight of a curve.
You mentioned that they have a vertical hump - Are they fastened down at the middle or just free floating? Sometimes the cast frog needs to be filed down(I think this happens when they are pulled from the mold while the plastic is still hot). As far as the throwbars, Atlas does have replacement ones if they become damaged(just call Atlas customer service).
The 'geometry' is not the same between brands, so a direct replacement may not be possible.
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
Jim,I should have been more clear on the time frame. Two of the turnouts began causing this problem - though less often - about three years ago as best I recall. Far too soon in my book. Recently, it's become much more frequent, and the third turnout has recently joined the ranks of the misbehaving.
The point rails are definitely the problem and exhibit the flaws I described. They're easily seen when viewed at track level and from above. The diesels are two-axle, and the steam loco is a 2-8-2. Not very long at all. Tightness of curve is not a problem.
Even when I lay the turnouts on a perfectly flat surface, they "bulge" up in the middle. I can press them down 1/8" or more. When in use, they're nailed to the roadbed to be as flat as possible. I've run the locos over them with and without track nails and get the same bad result.
I live in a state with basically no humidity, so no benchwork shrinkage here.
Sounds to Me, that the points are Not in gauge when set for the divergents route and either the flange is hitting that spot or it is riding on that spot and derailing. If the points are at an angle when touching the stock rail, the above will occur. They sound loose to Me. You said You used CA to try and fix the movement....but were You aware that You may have slightly corrected the problem, but is still there. You can bend the points so they blend better at a 90 degree angle with the stock rail and they should Not be blunt....they should be sharp at the leading edge when touching the stock rail. Just make sure there are no burrs. The very top leading edge of the points should have a tiny roundness to the leading edge...that will make the wheel flange ride better for the transition. If You have a loose truck lying around put Your finger in the center and slowly push the truck thru Your turnouts in every direction and watch what happens. It would work better with a 3-axle truck. I had stopped using Snap switches back in the early 70's and I have heard all kinds of stories about them.....but I have never seen one that could not be fixed.
It's also quite possible that Your Tortoise machines are not adjusted properly for a Snap Switch.......You are the first person that I have heard using a Tortoise on a Snap Switch. Sorry can't help You further........would be a different story if I were there. I have salvaged many turnouts that some would just toss.
Also make sure that there are no high spots/humps in the complete turnout....should be completely flat...I believe that was mentioned already.....including the plastic frog area.
Good Luck!
Frank