Question about turnout Geometry

[Irbricksceo]

Hello, I was just wondering. Do any turnouts, either alone or with spacers, serve as a decent Drop-in replacement for a piece of 22inch radius track? Thanks.

[Joe Satnik]

Dear Irbricksceo,

If you mean Bachmann HO E-Z Track, you can get pretty close with a #5 ,

but you will have to widen your 4' table top dimension by a few inches.

Give it a try on AnyRail.com track CAD program. 

It's fun, easy to learn, and free for the first 50 track pieces.

Hope this helps.

Sincerely,

Joe Satnik 

[jward]

atlas makes 22r switches, both with or without roadbed. these can be modified to work with ez track if necessary.

[electrical whiz kid]

If you have a tricky place and don't mind doing some refitting, "Central Valley" has  turnout kits that work with jut about any problematic situation on your layout.  I do not use "E-Z track", so am not familiar with it, but thought this may help you.
Rich C.

[rogertra]

One of the mistakes that many modellers make when designing track plans is having the main track use the diverging route of a switch.

This is never done in the prototype!

While it may look, to the average railfan, that it does happen, even if rarely, if you know anything about how real switches are designed and built and you look closely at the design and geometry of the switch in question, you'll notice that the main track does not actually take the diverging route, it just appears to.  Yes, somewhere out there there's bound to be an exception but modelling based on exceptions to the rule is usually not a good idea as it appears unrealistic.

However, I can see where, on a small model railroad, using the diverging route as the main can have its advantages.

However, scale modellers should really try to avoid using the diverging route on commercial switches as it's not prototypical.  If you can hand lay track, then that doesn't become an issue as you can then correctly design the switch with the correct geometry.

Here it appears the main track takes the diverging route, to the right, but if you look at the geometry you'll notice the track to the left, the Berger Yard yard lead, is actually the diverging route.  I could have just used a right hand switch but that would have been un-prototypical.

[Irbricksceo]

Hey all, thanks for the replies.

As this is not going to be too serious a layout, just a sort of side-project to keep me occupied while I pay my way through college, I am actually using the framework set on my old childhood layout which just came back to me from my grandfathers storage when they visited this month. As I have not had a good set up (just an oval on hardwood I take apart when not in use) I am eager to get it running.

it is the dreaded 4*8 as many starters are, and used EZ track (it would be too pricey to cut it all out although I could almost defiantly get that atlas suggestion to work. The big issue is that this bench-work actually had a border so the true dimensions loose about .75 inches on each edge.

rogerta

I love that pic, you really did a great job. While on a true layout, were I to make it, I would do what you are referring to (as yes, in general, the main would Never follow the divergent route) the 4*8 compounded with the framework set restrict my options (and it is those restrictions that deter so many from such layouts in the first place) So while, had i the ability, I would do as you said; I am afraid my hands are tied, nonetheless, thank you,  you post was at least an interesting read and at most invaluable insight into what goes into creating realistic switching.

[ebtnut]

Just to expand a bit, a standard numbered turnout (4, 5, 6, 8, etc.) is not a direct drop-in because there is a straight section through the frog area.  The numbers refer to the diverging angle - 1 in 4, 1 in 6 and so on.  There area turnouts made for modelers that do have curve through the frog area.  The prototype would also do this in a special situation, most likely in a tight industrial area.  And trolleys of course use curved turnouts in street trackage. 

[jward]

some random thoughts on model railroads vs real ones.

model railroads have severe space constraints not found on real railroads. thus we often need to do things that the real railroads don't need to bother with. roger has pointed out that real railroads  don't use the curved side of a switch as the main route. ( I disagree with him on this, and can cite numerous instances where the curved route is the mainline.) we often have to put the mainline through the curved side, or deal with some nasty s curve problems. like the real railroads, we adapt to then space available.

s curves are another problem that affects model railroads differently from the real ones. look at many photos of yards, and they appear to be one s curve after another. telephoto lenses magnify this effect. but the real railroads are usually using longer switches (#8s are considered sharp by real railroads, but are often too large to be usable on a small model railroad.) and much broader curves than we use. in fact, an 18r curve scaled up to real size is too sharp for most of the locomotives we run on them. a 6 axle diesel like an sd45 or sd40-2 would be restricted from running on curves sharper than the real life equivalent of 48r, a curve most of us can only dream of having on our layout.

another major difference is in yard design. for space reasons we usually build stub ended yards, but the real railroads have ladder tracks on both ends. we also tend to get by with far fewer tracks than the real ones have. if we have a turntable and roundhouse, it's usually shoved back in a corner at one end of the yard. most railroad yards I've visited (and I've been to many all over the east) have these facilities centrally located, of to the side if it's a small yard, or in between the eastbound and westbound yards in a larger facility. if it's a hump yard, the turntable is usually located near the hump. the net result is that a real railroad yard often occupies a triangular or diamond shape, while on our model lines the yard is rectangular.

given our limited space, we have to make choices. trying to model everything to scale makes a small yard look like a major facility which dominates the room we have. compressing things to fit the available space, but trying to keep the feel or context seems to me to be the more practical approach.

[rogertra]

some random thoughts on model railroads vs real ones.

model railroads have severe space constraints not found on real railroads. thus we often need to do things that the real railroads don't need to bother with. roger has pointed out that real railroads  don't use the curved side of a switch as the main route. ( I disagree with him on this, and can cite numerous instances where the curved route is the mainline.) we often have to put the mainline through the curved side,

Re-read what I wrote.  It may appear the prototype is using the diverging route as the main, but if you look at the geometry and know what you are looking for, you'll notice the main is not taking the diverging route as the switch is laid out so the "flow" of the main track favours what looks like the diverging route and what looks like the straight, is in fact, slightly "jogged" so as to give preference to the curving main.

All very technical and unless you've worked for the railroad or been involved with building switches, as a layman you may not notice the subtlety.   

BTW, only the suits in the offices and model railroaders call them "turnouts".  The guys that run the trains, working in the yards, maintain and build track and get their hands dirty while doing their jobs call them "switches".

Model railroaders adopted the term "turnout" way back in the mid to late 1950s(?) to avoid confusion over electrical block switches.

Cheers

Roger T.