I am in the process of planning my first H0 layout (Danish mid-sixties
theme) and has been recommended Peco code 75 for the trackwork.
My problem is that I would like some of my turnouts to have a radius
well above the 1524 mm of the SL-E188/SL-E189.
Ideally the turnout should have a radius of around 2200 mm (to model a
Danish 1:9 turnout with 190 m radius - and I would imagine the UK
prototype have used a similar size).
Obviously Peco doesn't provide this but I was just wondering if there
by any chance exists a solution (for example a UK manufacturer making
such a product, a modification kit, assembly fixture or something
I might be asking for the impossible here - but I do hope there is a
way through this, so any information on this is very welcomed.
I think you are wishing for the impossible here! Such a large radius
turnout will take an awful lot of space so most modellers compromise
with much tighter turnouts. Therefore Peco will never make the turnout
Other than making your own turnouts or having someone else make them for
you I don't think there are any options.
A possibility which requires much less work would be to take Peco's
curved Code 75 turnout and straighten it by cutting the webs between
sleepers and reconfiguring it. I have done this before with a Code 100
curved turnout to make a larger radius curved turnout for a specific
situation and it was a success. You need to leave one line of webs
intact and the turnout needs to be laid on perfect roadbed as it will no
longer be as rigid as originally.
Around the point ends area the webs should not be cut.
Sorry, Greg - not sure I follow you...
I believe all curved Peco turnouts have the same V angle as their
straight counterparts, so what will I gain by straigthen out a curved
To me V angle and radius go hand in hand (at least within the same
product line) - so what am I missing here?
"Curved turnout" is ambiguous. It may refer to a turnout where both legs
of the turnout are curved, or it may refer to a turnout where the
diverging route curves continuously from curved points through curved
frog. This was common practice in England and much of the Continent in
the past, but AFAIK is not longer the case. A straight turnout has
straight points, a curved closure rail, and a straight frog. This
ambiguity of "curved turnout" means that if both legs are curved, but
points and frog are straight, a turnout can be both straight and curved!
All straight turnouts have an effective radius, which the radius of a
section of track that could replace the turnout between its clearance
points (a few feet before the points, and few feet after the frog.)
There is no definitive relation between frog angle and effective radius
in a straight turnout: the length of the points and the radius of the
closure rail together determine what frog angle fits. North American
railroads use standard turnout dimensions, and the NMRA has used a
selection of these to specify RPs for turnouts.
You can bend a straight turnout so that both legs are curved, and there
will be no problems as long as the radius of the closure rail for the
inner leg is at least equal to the minimum radius of your layout. The
effective radius will still be greater than the minimum radius. I've
done this several times, without a problem.
You can of course widen the radius of a straight curved turnout the same
way. Just do it, and you'll see what I mean. Cut the webs underneath the
rails so that the ties can slide a bit while you fiddle with the radius.
If the turnout has a curved frog, you can still fiddle with its overall
curvature, but not to the same extent. But changing a curved #8 to match
a curved #9 should not cause any problems whatever. You'll just have a
turnout with varying radii in it, is all.
OTOH, if you build turnouts in place, you needn't bother with
predetermined frog angles, etc. Just lay down ties (sleepers) to suit
the diverging routes, lay the stock rails, then fit the frog rails to
gauge and solder them, then fit he closure rails, and then fit the
points. If you use track gauges and sight along the rails frequently,
you will get a nicely flowing, good looking, and smoothly operating
turnout. It's not difficult to do. And a lot less hassle than trying to
match some official specs.
Keep in mind that you are creating an illusion when you build a layout,
and the overall visual effect and smooth running are more important than
precise adherence to a standard. Prototype dimensions can and should be
followed in most cases, but you can and should diverge from them for the
sake of smooth running and aesthetic effect.
You can't have a continuously curved #8 (or any number) turnout because
the frog is curved - it will be continuously different numbers
I fully agree with both the above paragraphs. I'm building a typical
German Landerbahn through station with ladder formation at each end. If
I used prototypical length turnouts I would have space for three
parallel tracks, or using Pecos I can have 5 tracks :-) I'm also
building a gentle "S" curve through the double track ladder and scissors
crossover at one end. It's not possible with standard Peco components,
but by adjusting the radii and building the centre crossing I can
achieve what I want. It's not perfect but it's a trade-off between
appearance and operation. I've never seen a 1920 German railway station
and even if I had I would have seen it from platform level where precise
turnout dimensions could not be checked.
Practice in Denmark is that for turnouts with curved frog the turnout
angle is stated, i. e. 1:7.5, 1:12, 1:19 or 1:26.5. The frog angles are
a little less but frogs are nonetheless designated after the turnout
http://www.modelbaneteknik.dk/jernbane/spor/btj-bl6546.pdf shows a 1:7.5
radius 190m turnout from 1958 with curved point and frog in 45 kg/m
AFAIK US turnout numbers relate to the frog angle, which obviously is
_not_ the same as the turnout angle.
Going back to Peco HO (Code 100) turnouts, all three straight turnouts
have the same angle between the through track and the diverging track,
which by Danish practice would cause them to all be given the same
designation, even though the radii differ by 300%
Very true - however the point I intended to make is that the divergent
angle of a turnout can be significantly different to it's frog angle.
The only real way to obtain an accurate scale model of any given
prototype turnout is to measure it/obtain original plans and build it
While I use Peco Code 75 turnouts modified to the geometry I require, I
recognise that the only accurate scaled dimension in representing 1920
German Landerbahn practice is the guage.
However, the Peco models are the closest in appearance of any proprietry
turnouts I know of and I figure that if I hand-build then there would be
no possibility of my ever completing my layout :-(
I agree that it seems that the only way to accurately model the
prototype is to handbuild the turnout - and that will take valueable
time away from the overall goal of completing a layout.
However as I am in the planning phase - which includes the choice of
trackwork - I feel this is the time to collect all information
possible on that subject, so I can make an informed compromise between
the different manufacturers.
My no. 1 choice is Peco code 75 for I believe the same reasons as you.
At least I am not aware of any other ready-to-use H0 track products in
same code or less.
Reading about your modifications to the turnouts is very inspiring and
I think I'll have to try this out myself (as I'm still strugling to
make my theoretical understanding fit with your actual experiences)
One solution for me could then be to use SL-E188/9 for the 'smalllest'
turnouts (as a DK 1:7,5 approximation) and use a modified/handbuild
turnout for the larger ones (after all I expect 'only' 10-20 % of all
my turnouts to be larger than SL-E188/9).
After your replies I had another browse through the Peco catalogue and
found some components named Individulay. I'm wondering if they can be
used to build/modify code 75 turnouts even though they are intended
for code 82?
Thanks to all of you for your replies so far...
the planning phase is a good time to make decisions, except that you can
become stuck with them ;-)
I began with hand laid turnouts and Model Engineering Code 70 track with
the sleeper webs cut so that I could spread the sleepers out to the
correct spacing for my prototype.
(Code 100 in hidden areas to use up my old stockpiled track)
The track works well, except that if I haven't ordered enough then I'm
going to be in difficulties as I have to order complete 25 length boxes
for shipping USA/New Zealand.
The problem with turnouts is that they are not the same beast from
country to country nor railway to railway nor even era to era.
On the plus side, only people who have laid real turnouts and the odd
railway fanatic actually knows what a real turnout looks like. The rest
of the population has only seen them from a station platform or a
railway overbridge and then the view is generally very foreshortened.
I can only suggest you get plans for the specific (type of) turnouts you
wish to represent and then decide how precisely you wish to model them.
You may well decide Peco or Model Engineering or Mehano =8^) are close
I was happy enough with Peco Code 100 for twenty years - until I saw a
Proto 87 layout - ouch!
As for Individulay, I'm only aware of the original fibre based sleeper
strip stuff - do the (current) sleepers match what you're modelling? Do
you need to create rail baseplates? (etchings) Will the spikes allow
whatever wheels you're using to clear? ... Sometimes it's easier to
start from scratch ... Other times the compromises are so small ...
That very much depends on the normal practice of the railway or country
In Denmark a straight turnout has always been a turnout with straight
through road regardless of the design of the points and the frog.
Initially all turnouts used straight points and straight frogs, probably
becaused they were the easiest to manufacture.
In about 1907 Danish State Railways designed points where the point for
the diverging road was curved. The same set of point was used for all
frog angles so that the point radius and the closure radius could be
different. Frogs were still straight.
In 1922 a design was made with a curved point specifically for each frog
angle such that the curve through point and closure rail was continuous.
Designs for turnouts with straight frogs included 1:9 radius 190m, 1:11
radius 330m and 1:14 radius 500m. Furthermore a design was made for a
curved frog with radius 190m for a turnout 1:7.5 radius 190m using the
same set of points as a 1:9 radius 190m turnout.
The same turnout sizes were repeated in UIC60 which is used on most
lines today. Later on turnouts1:12 radius 500 m, 1:19 radius 1200m and
1:26,.5 radius 2500m with curved points and frogs have been introduced.
In Denmark, a "curved turnout" is constructed simply by using the parts
for a straight turnout, bending them for the desired main road radius
and adjusting the closure rail lenghts if necessary. Today where cast
manganese steel frog are used, frogs are made to fit the location.
That's precisely what I said. Sorry for not spelling out all the
implications of my initial statement, that "curved turnout" is an
ambiguous term. By simple logic, "straight turnout" is therefore also an
ambiguous term. In the part of my post that you snipped I pointed out
that a straight turnout can therefore be curved -- which also implies
ambiguity of the term "straight turnout."
Nice to know that in Denmark the RR has resolved the ambiguity. Would be
nice if all RRs everywhere used exactly the same terminolgy... ;-)
[snip interesting details about Danish RR practice]
Have a look at www.templot.com - in the "club", and the help pages,
there is a huge amount of info about the technical side of point
construction - even if you don't want to make your own the site
provides difinitive info about turnout construction. Well worth
a read even if only for interest (sometimes a Phd in Maths might
help - Martin is obviously quite good at sums!).
I have become... comfortably numb
I've looked at it, and marvel at the amount of information, the
precision and detail of the templates, etc etc etc.
Another good site is Fast Tracks, who offer machined jigs, laser cut tie
strips, etc, to enable precise turnout construction:
But IMO it's overkill. You don't need any of that. Just build the
turnouts in place to suit the actual location of the tracks. Last time I
did that, I had it done in about 30 minutes. I use three 3-point track
gauges to hold rails in place, and an NMRA gauge to adjust check gauge
and flangeways. Just make sure the effective radius of the turnout is
larger than your minimum design radius. Bonus: you get beautifully
flowing trackwork this way.
OTOH, if you want to make show-piece, foreground quality turnouts,
Templot looks like just the thing to keep you on track... ;-)
Indeed - I'm affraid I've become a bit pedantic since deciding on
0 gauge - it seems a terrible shame to spend hours building the
"perfect" kit and then get the track wrong ;-)
The interesting bit of my layout can be seen at :
It wasn't quite finished then, and I've since converted it to
0-FS from GOG-F, which is as good as it gets without going all
For those who have dowmloaded the (free!) Google SketchUp, the
file can be found at:
about 4 posts dowm - called Loft.skp
It's quite fun "flying" around....... the Templot track could have
been imported in 3d, but I did it in 2d as my PC struggles with 3d.
I have become... comfortably numb
Wow! In wouldn't even try to build such a complicated arrangement of
turnouts and crossings! I can see where Templot would be an enormous
help in laying out the sleeper locations, etc.
I trust we'll see some in-progress pictures from time to time?
Well, I've got the baseboards done now (not over interesting
photo wise but I'll add one soon), and found a lunatic
who can plane the point blades... just having a burst of
activity on the Warship & wagons front to clear some space
on the work bench (aka dining room table).......
Still struggling to find some 0-FS track guages though -
anyone come accross any?
I have become... comfortably numb
There are two overall ways to build a turnout:
- constant curve throughout the branch track.
- a collection of straight and curved components making up the branch
US turnouts generally use frogs which are straight (the casting can
often can be used for either left or right handed turnouts)
The points are straight and then the section between point and frog
provides the entire curve.
European turnouts are often the constant curve type where the frog is
cast with the diverging rail curved, along with most other diverging
Peco "Set-track" turnouts are the extreme form of constant curve
turnouts as they are intended to match the standard track sections.
Peco (Code 100) turnouts all have the same exit angle, in spite of being
2', 3' and (6') radius. The difference comes in the amount of curve and
straight in the diverging track and probably the frog angle differs
fractionally for each radius.
Look at the 2' radius diverging track - it has an angle and curve to the
points, an almost straight section to the frog and a slight curve
thereafter. The 3' radius has much the same point angle, then a gentle
curve to the frog.
The large radius divergance is larger than the logical curve from points
through the frog angle to the toe.
(I'm using the Code 100 Peco comparioson as I don't yet have examples of
all the Peco Code 75 turnouts)
Anyway, bottom line is that just because the turnouts all have the same
exit angles doesn't mean the frog angles are equal!
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