It is right that the frog

It is right that the frog angle of all three different Peco code 75 or 100 turnouts is 12°. The closure curve goes through the frog.

Peco offers templates: https://www.peco-uk.com/page.asp?id=pointplans

On a German website I found the following radiuses:
- small        24''
- medium    36''
-large:        60''

How correct these are I don't know. Better compare the templates to a real turnout or a Fast Track template.
Regards, Volker

My turnouts are all buried in

My turnouts are all buried in boxes from moving but eventually I'll get them out.  I think I have a Peco Code 100 large in there for comparison but thought in the mean time I'd get some feedback.  Here is some feedback on another forum:

Looks like ...

Thanks Joe et. al.As some of

Thanks Joe et. al.

As some of you may know, I am considering using Peco code 100 large turnouts in a future staging yard - a decision which is not set in stone yet.  With that idea in mind, a number of sources were/are putting the frog angle at 12 degree's which if you don't consider anything else, would lead you to believe the Peco code 100 large is equivalent to, or sharper than, a standard #5 turnout. 

The above being tru, If ones goal is to stay with a minimum of #6 turnouts on all mainline and staging track for best operation including long rolling stock, then one might be inclined to steer away from Peco code 100 Large.  But as I am digging deeper, it appears the Peco code 100 large may really be a bit closer to a #7, which if true, should make them a good option for "any rolling stock goes" staging yard.

Jim, I would suggest not

Jim, I would suggest not thinking in terms of frog angle simply because it is changing all the way through the turnout. The curve radii posted above were also posted by another. Think of a series of pieces of track with a 60 inch radius till the rails are 12 degrees along the curve from the starting point.

An example a 1/3 section of 18 inch radius will take an atlas number 6 switch and make the track from the diverging leg parallel the straight leg, which results in a ten degree difference.

In the case of the Peco a section of 60 inch radius track that curves 12 degrees away from the tangent would be needed to match what was in the turn out.

Sharper curves would result in smaller sections of track needed but keep in mind the reverse curves that will be involved. The 60 inch curves work reasonably well with each other when used as crossovers so the reverse curve does not seem to be an issue. I have backed long trains through them with out issue (more than 100 cars) and I put that in since you are using these for staging and if single ended may be backing full length trains through them on your layout.

Joe F. mentions the 60 inch radius in one of the earlier issues of the magazine discussing how cars behave on a 60 inch radius in HO scale. For most applications they behave the same as if they were on straight track. I suspect you will be fine with the use of these. 

The cross over just in front of the locomotive is one of these pairs used on the main line of our club layout. There is a section of straight track between them and the tracks are on 3 inch or 2 1/2 inch centers. I have heard both figures and suspect it might be both figures as the builders of our club layout had a loose interpretation of standards.

Jim, I would suggest not

 Rob, one step ahead of you - hence this topic. 

I sensed already there was more to the story than the 12 degree figure being reported and wanted to dig a little deeper to get to the bottom of the truth.

I have read some conflicting information so wanted to try to get at the truth, is the Peco code 100 large turnout have a closure radius that is sharper or more gentle than the standard #6, which is my layout minimum basically.

More recent feedback seems to be consistent with yours, that the Peco large should be fine for long rolling stock.  Many have state that was their experience, but I wanted to see some dimensional info as well as a Reality check".

Thanks for adding your comments to this conversation.

Cheers, Jim Fitch

Compiled from the Peco site

Hi Jim and all,

The following info has been posted on here previously. It was compiled directly from the Peco website. 

First some info on Peco collated from the Peco catalogue webpages with effective radius and divergence (in degrees out of 360 for a circle) The E prefix in front of the number is the Electrofrog catalog number. No E = Insulfrog catalog number. 

For Code 100 rail 

Set track radius #2 (ST240-ST242) 438mm (17 1/4")  Insulfrog only. 22 1/2 degrees

Short radius (SL91/SLE91-SL92/SLE92) 610mm (24") 12 degrees 

Medium radius SL95/SLE95-SL96/SLE96 914mm (36") 12 degrees

Long radius (SL88/SLE88-SL89/SLE89 1584mm (60") 12 degrees

Peco Set Track Curve Radius

R1 - 371mm (14 5/8")

R2 - 438mm (17 1/4")

R3 - 505mm (19 7/8")

R4 - 571mm (22 1/2")

For Code 83 (US profile)

#5 - (SL8351/SLE8351/SL8352/SLE8352) 660mm (26")  11.4 degrees 

#6 - (SL8361/SLE8361-SL8362/SLE8362) 1092 (43") 9.5 degrees

#8 -  (SL8381/SLE8381-SL8382/SLE8382) 1702mm (67") 7.15 degrees 

Hopefully this should resolve some of your worries, if you add in JoeF's  previous posting on frog #'s.

In summary, Peco's long radius code 100 is much closer to a #8  than a #6,

John, So if you went on the

John,

So if you went on the info on Peco's site, the code 100 large would show as 12 degree and one would be led to believe they are sharper than a #5.  I want minimum #6 on my mainlines so I would reject the large code 100 based on that limited information. 

Thankfully that appears to not be the end of the story - others filling in missing details which changes things and the Peco large apparently is actually broader in the diverging route than a #6, rather than sharper.  Or am I not reading the info right?

Jim, just for purpose of a

Jim, just for purpose of a similar comparison a substitution radius for a fast tracks turnout number 6 is listed at 45 inches in HO scale, So if you joined a series of 9 or 10 of them together by connecting the curved leg to the single leg ot the turn out you would have an approximate 45 inch radius although it would not be smooth due to the short straight sections. The 60 inch would be broader still.

Sorry, I fell into the frog angle trap

Sorry, I fell into the frog angle trap.

Peco Streamline code 75 and 100 turnouts have an angle of 12° between straight and diverging track for all radiuses.

They are designed that you can combine different radiuses without filler track pieces and get a track distance of 52 mm (2.05''). The link shows possible combinations with the same kind of turnouts. You get the same results with different turnouts: http://www.wieduwilt.org/plaene/fiddleyard-forenbahn-01-grosz.png

In Europe wie don't look at frog numbers, here the diverging curve radius is given. Going from one track to a parallel track with Peco 12° turnouts means that have a bit more total curvature (2x12=24°) compared to an NMRA turnout with the same radius.
Regards, Volker

PECO Code 100 Large Turnout radius

On my previous layout, I replaced several Atlas Custom Line #6 turnouts with Peco Code 100 large-radius turnouts, and they fit well without much rework, just a little cutting and fitting.  The switches are different shapes (the Atlas turnouts have the straight track extend further than the curved route), but the overall shapes and sizes are similar.

When we talk about the radius of a turnout, there are really two different radii to consider.  The first is the substitution radius - if you used the curved leg to replace part of a curve, what radius would be the closest match?  This affects how well two cars coupled together would run through the turnout, and how much overhang there would be.  It would also affect the sharpness of the S-curve where two turnouts are connected, such as at a crossover or the first track in a yard.  With a 60" substitution radius, the Peco turnout is far larger than what nearly anyone would be using for a regular curve, so this should not be a problem in your staging yard.  It looks to me like the Peco Large and the Atlas #6 should have roughly similar substitution radii.

The second relevant curve is the radius of the closure rail.  This is the curve between the switch point and the frog.  In a standard U.S. turnout - like the Atlas model - this is much sharper than the substitution radius, because there are straight sections in the frog and the points.  A tight closure rail radius can cause problems for equipment with long rigid wheelbases, like cars and locomotives with six-wheel-trucks and larger steam locomotives.  For the Peco, because the turnout has a continuous curve, the closure rail radius should be close to the substitution radius, and much bigger than in an Atlas #6.

So the Peco Code 100 large turnouts should handle your equipment at least as well, and perhaps better, than a standard #6 like Atlas.

When degrees ain't degrees

Hi Jim and all,

The US tends to use "degrees of curvature" based on a chord length to specify frog angles etc as opposed to elsewhere in the world where the hobby uses radius and the degrees of rotation (out of 360 for a full circle) measured about a centre to specify the tightness of a curve and how far it extends. BIG CAUTION - Degrees of curvature do NOT equal degrees of rotation.  This is a major source of confusion when which "degrees" are not specified. 

The primary advantage of using degrees of curvature is that a #8 frog is a #8 frog regardless of gauge or scale. However many real railroads throughout the world use the actual track radius to specify curvature rather than "degrees of curvature".  This track radius has a major influence when setting grades (compensated versus uncompensated) and speed limits. This is the territory of the real railroad "engineers" (design and construction engineers and not locomotive drivers as used in US/North American parlance) 

Volker has correctly pointed out that the Peco design for streamline code 100 track gives a 52mm track spacing if 2 of the Streamline  turnouts ar butted against each other, The reason the angles vary for code 83 is to maintain the same track spacing as for Code 100. For Peco's SetTrack, where the track swings sharper and the angle is a larger 22.5 degrees, the track spacing comes in at 67 mm. 

I'm hoping that this helps clear up some of the confusion when "degrees" ain't "degrees",

"The US tends to use "degrees

Actually  US frogs are denoted by units of run required to create one unit of offset. A #6 requires 6 feet to offset 1 foot for example. Degrees of curvature is the sharpness of a curve derived from the amount of central angle (delta)per 100 feet of chord length(which also determines radius).....DaveB

Confused again & Fleischmann Profi-Track turnouts

Well I thought I was getting a handle on this 'turnout designation/specification', but now I think I am as confused as I ever was...ha..ha.

I have a whole lot of Peco turnouts and Fleischmann Profi-Track ones that I intend on using on my new layout. I can not find full scale, printable templates for the Fleischmann ones, so I guess I need to just trace them out from the turnouts themselves.

Since Peco and Fleischmann are both 'european' would I assume that their turnouts are similar?....that the curvature is carried all the way thru the turnout??  

@ jimfitch

Jim, there are turnout plans on the Peco website: https://www.peco-uk.com/page.asp?id=pointplans

@ Brian

If you want to run old Tin-Plate stuff with pizza cutters, it's o.k. But if you intend to run here with NMRA conform wheels, then forget these Fleischmann turnouts all together.

Lutz

So the Peco Code 100 large

Steve.  Thanks for examining the Peco code 100 turnout geometry all the way through the turnout.  As well or better than the standard #6 works for me!

Alcon.  For anyone wanting to read up on what Steve discussed on turnouts, John Armstrong discusses the nomenclature and elements in an understandable way in his book Track Planning for Realistic Operation.  I've had my copy since the 1980's and it's worth having - mines well worn.

Brian.  Some of the confusion comes in because Peco are manufactured in the UK and the traditional code 75 and 100 turnouts follow their standards.  US have their own for model trains which translate the same scale for scale because the # number designation is based on a ratio of diverging.  e.g. a #4 diverges 1 in 4, #6 1 in 6.

John, no worries.  I learned those differences in degrees in high school geometry and trig classes.  I has been interesting in my D&RGW books to see Jim Osment working as a track engineer working on real world track curvature.  On the Front Range, the Big Ten curves of course get their name because they have 10 degrees curvature.

Fleischmann and Peco code 75

Fleischmann and Peco code 75 and 100 turnouts are similar with the radius of the diverging track going beyond the frog.

On Fleischmann standard turnouts the wheels roll through the gap between closure rail and frog on their flanges. RP25 wheels will fall into this gap.

On Peco code 75 and 100 turnouts the gap is small enough so that RP25 wheels can cross the gap without falling into it.

On Fleischmann high speed turnout the moving part of the frog closes the gap.
Regards, Volker

I read comments as follows

I read comments as follows regarding the Peco code 100 turnout by Sheldon over at MR forum:

Any reaction to the above?   It didn't really make sense to me.

Bottom line

The bottom line is he’s saying wheels on a curve like to keep going in a straight line, so a frog on a curve increases the chance the wheels will go down the other route with a frog on a curve.

Straight frogs minimize that tendency, that’s all.

He's also saying to protect a curved frog better, modelers may add shims to the guard rails to keep the wheel flanges well away from a curved frog point.

Thanks Joe.  The comments

Thanks Joe.  The comments seemed to be more reason why another modeler didn't like Peco code 100, but I really couldn't find any logic in why the info there was a negative and a reason to avoid them.  It seems like a lot of common sense verbiage that should be true for any turnout.  *shrugs*

Curved frogs = bad?

It's true curved frogs are not as good as straight frogs, considering the laws of physics and no guard rails. It's also true if the guard rail check gauge with the frog is off (too wide) or the wheel gauge is too wide, curved frogs are worse.

But if the wheels are in gauge and the check gauge at the guard rail is correct, then curved frogs are no different from straight frogs as to performance.

The bottom line is with curved frogs, you can't be as sloppy on wheel gauge and check gauge as you can with straight frogs. But then being sloppy with trackwork in general is just an invitation to Murphy, regardless.

The main caveat with commercial turnouts of any brand -- don't trust them -- check them, always. And be ready with the skills to fix them when you find ones that are off. In my experience and testing, more are off than in spec. Nothing against the manufacturers, it's how mass production works -- stuff varies unless you spend a ton and go overboard on quality. But then who wants $50 turnouts?

True.  As it is with this

True.  As it is with this hobby, you'll need some skills one way or the other to get the best results.

When we talk about the radius

That's encouraging for both the Peco and  Fleischmann turnouts I have

Give up on Fleischmann?

I'm not ready to give up on them just yet. Overall they appear to be a quality product,...German quality.

Yes the depths of flog areas may be a little large, but I'm not even that sure of that at the moment? I drug a few out of my boxes and by eyesight they don't appear to be any different than some Atlas turnouts I have. And I have a few Pecos that appear to have a greater depth.

On another subject thread one gentleman has noted that some earlier Pecos had metal inserts made for them. I may investigate that possibility for my Fleishmann's?

I do recall reading a long time ago where it was suggested that a plastic shim be glued in place on the Peco guard rails to make the gaps smaller for USA model wheels. Perhaps we need to make similar additions to the Fleischmanns?