Using the standard atlas snap switch turnouts…I want to connect 2 together at the curves and use as a crossover from track to track. Does anyone HIGHLY suggest a short straight be put between them. I think I have read where it is a good idea for trains to cross through smoother. However I want to keep 2 tracks parrallel and as close together as possible.
Is anyone connecting them without a straight and having no problems?
Thanks
For a simple crossover, you can connect the curved part of the turnouts together directly. The spacing of the parallel tracks will determine if you need a short straight section between them. IIRC, the direct connection is for 2 inch spacing (measured at track centers). A wider spacing of the parallel tracks would require a short straight section, but I wouldn’t know which one without knowing the spacing.
Don’t forget the insulated railjoiners at the crossover.
One reason for a straight section is to lesson the severity of the S-curve cars have to go through to get from one track to the other. I think I’ve seen recommendations that a straight section as long as the longest car is needed to negate the effect. I recommend you assemble some track as you are suggesting and pull a string of cars through. Make sure they make it through without derailing. How long are your longest cars?
Jim
According to the Atlas book:
For the custom line #4
Parallel straight
spacing length
2" - 0"
2.25" - 1"
2 5/8" - 2 3/4"
3" - 4.25"
For the custom line #6
2" - 0"
2.25" - 1.5"
2 5/8" - 4"
3" - 5.75"
No idea why they use 5/8" rather than 1/2".
??? These are Atlas turnouts.
How much space do you have for the crossover?
If the straightaway is short, then the snap-switches may be your only choice. If you’ve got a bit more room, though, consider using a #6 turnout instead. You’ll greatly reduce the S-curve effect, even if you put the curves very close, because the degree of curvature is so much less. Also, the less severe curves will allow you to run trains across much faster without problems.
The problem with crossovers is the S curve. On snap switches you can’t put a long enough straight in place and keep reasonable spacing. The straight needs to be as long as your longest piece of rollingstock to avoid the problem. You mitigate the problem by using broader turnouts such as #4 (really 4.5 for Atlas) or #6. One advantage of #4 and #6 over snap switches is they are straight from the frog as opposed to continuing the curve. This means that a shorter straight needs to be added. Plus the reduced angle allows a longer straight while maintaining a 2" spacing. The trade off is that the linear distance of the crossover is increased.
If you’re running long cars or engines you should try to stick with #6’s, short cars and engines may work with Atlas #4 (4.5) but should be tried first to make sure. Snap switches should be avoided but may work with very short equipment and/or truck mounted couplers - pushing will probably be a problem, highly recommend you test this before committing to it.
Enjoy
Paul
Thanks guys…I think you have answered my question. It seems while the snap switch could work okay everyone is suggesting a minimum #6 for good use and low problems.
If anyone is using a #6 to run 2 parallel track together…how far apart are your tracks and how long of a straight are you using between your #6’s.(or better)
Your input is appreciated…I am putting much research into building a nice layout without a large learning curve…I hope this forum of people can use their knowledge and experience to help me out…so far they have been a great help.
Here’s another vote for #6’s. I can run long passenger cars and auto racks through mine no problem. Your going to limit yourself with snap switches.
I used a straight track around 6-8"'s between mine.
I’m using Atlas standard switches with no straight section in some places and have no problems with an Athearn 4-6-6-4 pulling nine Rivarossi 85’ passenger cars. I do slow down to go through them, just like the prototype would. The only engine that has problems is the Spectrum 4-8-2 – the pilot wheels have trouble staying on track at various places. I like the appearance of trains going through S-curves, so I have several on my layout.
Have you considered “double slip switches”?, Perhaps, they are only useful in yards, where slow speed switcher locos are being used to gain access to all of the closely spaced tracks. My long mainline passenger cars and locos never enter the yards, so the S curve problem never occurs. Bob Hahn
A crossover between two parallel tracks is actually one of the few places where you don’t want to add a straight between the s-curves formed by the turnouts unless it’s absolutely necessary to get your desired track-to-track spacing. And that’s the benefit of choosing higher numbered turnouts (like #6s) for the crossovers – even though there is an s-curve formed, it’s fairly gentle.
Byron
Model RR Blog
Hey, jlugar - I presume that you have seen the posting by Texas Zepher, actually before you posted your question, giving the specifics about track spacing vs. straight-between-turnouts. If not, look back up earlier in this thread.
Atlas has evidently designed both the Customline #4 and #6 turnouts to give a 2" parallel-track spacing if connected face-to-face in a crossover. The turnout # gives the diverging ratio (by definition), so if you want a wider track spacing with the #6, each 1/4" of spacing requires a 61/4 = 1-1/2" straight section. With a pair of #4’s (which, as already pointed out, are actually #4.5), you’ll need 4.51/4 = 1-1/8" of straight.
I prefer the Super-Track 83 #6 turnouts, because they don’t have the funky truncated ties at the end to clear the railjoiners, and these definitely need their diverging leg trimmed off for a crossover.