Radius

Run some equipment through it, and see what happens. With that short section, if you have issues, it might be worth a small bit of hand laid track.

Whatever Flows

The smoothness of the transitions even with the lower radius should not be an issue. The short radius is well short of the wheelbases of your longest equipment . The best bet for this track arrangement is to set the positions of the turnouts and handlay or use flextrack in the joining sections to assure a smooth transitions as opposed to trying to force a fixed radius curve section into the arrangement.

Espee over Donner

If a regular curved turnout =

If a regular curved turnout = double curved turnout, is a standard turnout a single curved turnout?

short answer

Yes - by the OP's definition

Test it

Brian, there really is no substitute to pushing some cars through it to see how the behave.  And perhaps even hooking up a bit of track on either end and running a long wheelbase engine through it.

Looks OK from above, but kinks are often much more easily spottable by sighting right along the top of the rail - do that from various angles and see how it looks.

(The "double curved turnout" thing really is non-standard terminology, it's just going to confuse people who you'd rather have thinking about the question you wanted to ask.)

Double Curve Terminology

I believe it is a 'British' terminology,.... that Peco itself utilizes.

Personally I find it much more descriptive of the turnout,...denoting double curves, not just 'curved turnout'.

Looks pretty smooth

I'd think it would work with shorter transition era equipment, say 50 foot cars with short overhangs. Might be a problem for modern era cars with long overhangs and extended cushion draft gear. As mentioned above easiest way to know for sure is test run some of your equipment on it....DaveB 

No Running Track

I do not have any operating track laid out. I guess I could get a power pack out of my trailer and hook up a temporary test track. ....Just hadn't wanted to unpack a lot of stuff and clog up my working space with trains when I need to keep it out of the way of construction.

Guess I'll have to break down and do it.

One of my major concerns with the short piece of tighter radius track is how it might treat a steam engine with more than 5 big drivers in a row,...such as a 2-10-4  Broadway Ltd loco of which I two.

Certainly the articulates should not have a problem here with this overall curve?

But these modern steam models have good side-play in their drivers that allow 24" min radius. And I'm not asking these locos to go around a full circle of this small radius at this point in the double crossover,... just traverse a 3" long piece.

As someone on another forum offered...

"One of my major concerns

  If they can't get around the curve just restrict them to other areas of the layout where they can fit. The real railroads do it all the time, certain equipment is just not suitable for all tracks so it gets a restriction in the operating rules ... DaveB

Minimum Radius...

...for the PRR & C&O 2-10-4 according to their website is 24". SO even if you had a short 22" radius I doubt you would have trouble.

Why not mock it up completely and try it before adding it to the layout. use flex track and eyeball it

I believe it is a 'British'

Could be, but with this newfangled terminology, it's like trying to force a bunch of American old dogs to learn new tricks.

Stop that!   

And me being married to a Brit but still resisting change.  Of course my wife has been resisting changing over to American terms, stubbornly.  She goes into a bank to "deposit" a check, but instead she tells the teller she wants to "pay it in" and they get confused.  I keep telling her if you don't want confusion and trouble, USE THE RIGHT WORDS.  Nope, still stubborn.

I can see why Americans changed some British terminology because it's American terminology is more abbreviated, words spelled with fewer letters.  It's practical economy.

Double curved turnout = curved turnout (one less word - you can say it easier with fewer letters - readers here in America universally understand what is being refereed to)

Colour = Color (one less letter, saves on electrons and the u is superfluous)

As you can see I'm trying to convert Brian over to American terminology. It's a tough job but I'll keep trying!  

Its like trying to teach me

Its like trying to teach me to use some of those multiple abbreviations that many smart? phone users are using these days,....I call it dumbing down America.

Kids will learn this rather than read and learn proper language.

Brian

I threw that into 3rd planit.  I assumed adding 12 degrees of curvature at 24" radius on the outer leg of the curved turnout, then tried to connect a track on the inside leg.  To do that, I need a curve of slightly less than 18" radius.  12 degrees of curvature, of course, since the PECO switches are set up to use that same divergence.If you want, I'll email you a jpg.  I'm not bothering with the embed process in this forum. 

Blair

Peco X problem

I think I am going to drag out a power pack, etc and give this configuration  a full scale test.

Yesterday I discovered a problem with some of my NEW Peco crossings. Four of my new Pecos had problems,...2 had plastic joiners in a few of the tracks had 'dips' in them, and 2 of them had little tip projections into the flangeway.

These were discovered when I experimenting with running a model 6 axle tender over them. Granted the flanges on these wheels were ever so larger than standards these days, but it was just enough to cause them to bump way up in the air as they encountered these blips in the flangeways. And I double rechecked the gauge on these wheel sets, and they were right on.

Whoa there.  Not trying

Whoa there.  Not trying expectingLMAO ROFL BRB etc.

Just "old school" model train terms that go back to before I was born.  Now for some more old school.  Your assignment is to get out an old fashioned chalk board and wriite "curved turnout" 100 times.  

It's a tough job but we will re-program you back to the American train lexicon.  

Correction, make that

~23" radius on the inner, with a 24" on the outer.  And if I increase the degrees of curvature to 24 then that inner radius has to decrease to ~22.  So it would appear to me that as you increase the curvature, the inner radius has to shrink.  If I increase the outer radius, that inner radius has to decrease, so it's a losing battle, I think.  Tell me a bit more about what you're trying to accomplish(e.g. what angle to you wish to achieve, etc.) and I could mock it up for you.

Blair

Sent you a private message

Sent you a private message Blair.
I'll have a closer look at this after breakfast this morning with a neighbor,...my birthday breakfast

Happy Birthday.

Happy Birthday.

sent you a note back

with three simple depictions.  Let me know if you want more variations.

Blair

Classic Crossovers

Blair, I rediscovered this posting by you

I'm using a small X as well.
 

I have a larger X by atlas, but it has a lot of plastic in the middle creating some long 'no power' to both rails.

Yes & No?

And Rob, I found this posting by you,...BUT I also remember seeing a posting by you that indicated you could back 100  car trains thru these Pecos without problems ??

The configuration looks like

The configuration looks like it should operate smoothly.  Regarding appearance: I've had a few area's in my last staging where track alignment may not have looked pretty or even, but as long as the rail has a smooth flow to it, I expect rolling stock will operate well over it.

This curved ladder isn't all even, but it flows:

The two turnouts in-line on the left side are Peco's.

the Suspect Tender

This is the tender that had the suspect wheels that encountered the problem thru those X crossings. It came with a nice IHC Mehano steam locomotive built in Slovenia.
 

I won't really describe these wheels as 'cookie cutters', but I guess their profile interacted badly with the defect in those Peco X crossings. They do not seem to have a problem with the std Peco turnouts, nor with any of the multiple Atlas turnouts I had on my old Central Midland layout.

First stage of

First stage of testing

Yesterday I got one of my DC power packs and several locomotives out to see what happens when I try to run trains thru the 'custom double crossover' I am proposing. I did a rather 'slap it together' job in the interest of brevity, and not wanting to cut up too much track until I arrived at a final solution (so please excuse the blue tape holding things in place temporarily.
 

Regrettably I continued to utilize that same short piece of 22” sectional track, just to see what would happen. Not only was it marginal in curvature, but it had slighty deformed ends I discovered with a close up photo,...here...
 

What turned out surprising was that all the trains I ran through this route experienced NO derailments or noticeable problems with this short decreased radius track section,...even my Broadway Ltd 2-10-4 C&O T-1.

However the long driver 2-10-4 did NOT like to make the right hand turn after exiting the curved Peco (dbl curved) turnout. Its front driver would consistently jump the frog of that reverse curve.

All the other locos and cars did NOT have a problem here, even the long Bachmann Northern 4-8-4 that ran over this route multiple times, slow-fast, fwd-backward, pushing-pulling those double auto racks.
 

The 6 axle Proto E8 did not have a problem. That IHC tender did not have a problem once I substituted a better Peco short X.


 

Perhaps I forgot to mention that I replaced the 3 other standard Peco turnouts with the 'large radius size' verses the 'medium radius sizes' I originally sought to use.

 

I became so engrossed with making this particular route thru the double crossover work, that I forgot to test the other route,...the one with a more direct S curve.      I will have to do that today.

I also discovered one other IMPORTANT item,....how lousy those metal track connectors are for transmitting electricity along the rails. They either MUST be soldered, or feeders run to every little section of track !!