3 Way Turnouts,...Peco, Roco, Casadio

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Over in this discussion thread I got into discussing some differences between the Peco & Roco 3 way turnouts I was considering for dividing out the trains to my s staging areas.

ROCO 3-way (DCC use?)

I've debated with myself over the use of a Peco or a Roco 3-way turnout to distribute my trains backing down the helix into one of 3 areas of staging. I've now chosen to go with a Roco one to start out with, but I am making sure it can be replaced fairly easily with a Peco one if that presents itself.

So my basic questions are about any problem areas that anyone has experienced with using this brand turnout on a DCC track plan?? I have looked it over using a meter, and thus far do not detect any problems.

It does appear to have metal frogs that are insulated from the rest of the track(s),...and they might even be made live if so desired. Interesting how the frog point itself is isolated away from those rails leading off from it,....thus no wheel shorting going to occur here,..so I doubt there would be the requirement to insulate those frog rails like we do with Peco insulafrog turnouts in DCC application


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I got this reply on another forum,..

A bad decision.

And still worse to place this antique 3-way switch in the staging area. And even more worse when the staging area is under the layout. And the most worst case when acessibilty is restricted too.

These Roco 2,5mm (Code 100) switches were made in the 1970's when in Germany were the peak time of every manufacturer has it's very own works standards in respective to wheelsets. So these will work fine with "narrow gauge" wheelsets of 1.6mm deep flanges and 14,0mm back-to-back measure. Your rolling stock equipped with these, everything is fine. But with wheelsets according to NMRA S-4.2 ... rolleyes.

O.K. it's your decision, your layout and at least your hassle with these switches. I ripped these 3-way switches out of my former layout before 3 decades ago and never used it again.

You need fast angled wheels

That is the type of wheels you will need for the Roco 2,5mm switches to run flawless over them. And note, the back-to-back space has to be only 14,0 - 14,2mm for the wheelsets to be safely guided by the guard rails to the correct side of the frog tip. The Roco 2,5mm switches are far away from any NMRA Standards and they are definitely not the MOST Reliable Turnouts.

So a frog of an Roco 2,5mm switch looks alike after I had rebuilt it to meet NMRA Standard S-3.2 in all aspects. Now wheelsets according NMRA S-4.2 will run over the frog and the whole switch without subsiding or derailments because this danger is eliminated durable. Because switch and wheelsets are fully compatible each other.
I responded,

"Nice shimming job sir. What did you use....plastic shims??

I do realize the flangeways in the frog areas of the Roco are rather wide, but I don't quite understand how that affects derails. I rather think it likely permits a very slight more wheel drop (subsiding as you termed it) in that frog area with the closer fitting guard rail. But I would be more concerned that the whole axle is drawn more towards the frog side resulting in a possible picking of the frog.

I found that both the Roco & Peco turnouts need to be shimmed up to be more fool proof,...particularly those that had tighter radi,...like the 'small' size Peco's, and the small size Peco wye (Y). But those shims were needed ACROSS from the frogs,...to draw the axles over towards the outer rail (away from picking the point of the frog).

I would ask 2 questions of you:
1) Did you experience more of a problem with steam engines than diesels?...(particularly multiply inline driver steam engines)
2) Did you notice a picking of the turnout up front on the point ends of the turnout,...where the rails are required to lay closely together.?"


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I looked at that Roco more closely today, and particularly the frog area where you added the shims. I can see now where those shims you added cut down on the length of the space the wheels would have to jump over when traversing that space. What thickness shim did you use?

I believe I could fashion similar shims out of .020" styrene for the frog area, then add .011" shims on the outer guard rails.

BUT since this 3-way will NOT see any mainline activity, and since it appears to be not a derail problem for me (by my testing), I think I will leave will enough alone. As I've said at least I have this 3-way in a very accessible location, I can always go back and modify it or change it out for another one.

I have another thing working in my favor I believe. Most of my trains will be backing down the helix to staging, and there is a declining grade there that should be easier on backing those trains,...drifting backward, not driving backward into staging tracks.


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Roco 3-way testing

Yesterday I set up a test track on my outdoor work bench to do a little testing on that Roco 3-way turnout. I ran the engines thru the various legs of the 3-way both in both directions to simulate the trains backing down into staging, ....and pulling thru the turnout if coming face first down the helix,..... and face forward coming from staging to enter the helix.

I only had 3 longer diesels with 3 axle trucks handi yesterday, and several freight cars. I experienced absolutely NO PROBLEMS with these.
I had a mountain steam engine handi. It also experienced no problems.

I happened to have this little switcher hadi and gave it a try,...at very slow speeds it stalled a couple of times on the dead frogs,...but no derails.

I also had a brand new BLI Trackmobile handi, and it when thru the Roco just find except for some stalling on those dead frogs if going to slow.

I had only one 4 axle truck loco handi, a brand new SF geneses F7. Again NO problem with Roco


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I picked up a variety of other locos to run thru my 3-way,...and make note that I ran them thru all 3 routes, and I ran them in both directions.

I was a little surprised that I didn't have a whole lot of locos with 2-axel trucks vs 3 axel trucks. Here is one, a Proto 2K C-liner that I had added the PRR style antennas onto.

I wanted to make sure those double autoracks would not have a problem with their relatively small wheels and long bodies.

One of my favorite diesels, the DL109. These are really smooth running engines with a LOT of weight,....real pulling machines. I have some extras of these that may be employed as 'helix specials'

There were a couple of locos I was seeking out in particular,...these Spectrum CSX 8-40CW units that have very small flanged wheels and 3 axle trucks that enjoy finding problems areas with track work. I use to use them to find problems on my old layout. I wanted to see if they would be upset by this Roco 3-way.
I ran them separately and finally together with their fuel tender. NO problems.

I did discover one problem with this combo,...the ladder on the fuel tender was just a bit too long and stuck out a little bit,...interfered with the turnout control solenoid

Going to have at least 4 RDC, so I thought give them a try...no problem, and nice running Proto 1000 series

I've got a whole Acela train that will likely occupy one of those staging tracks. Didn't get the whole set out, but thought this HHP-8 would substitute for now.

At an earlier time when I was testing some longer steam engines threw various combo of turnouts placed at the tail end of a reverse curves, I discovered that the trucks on the long range tenders of the Northerners would clip the corners of the solenoids housings. Had to trim the excess plastic tips off these two areas denoted by yellow circles,...


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Are the photos showing up on these postings of mine?

(I'm using a copy/paste method of posting here to save time and extra work).


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Metal Frog Shape Variations

This experimentation with my 3-way turnouts, and a recent auction for the brass 3-ways has prompted me to have an even closer look at a variety of frog shapes in older turnouts. So I went back into my box of 'oddball' turnouts I had saved.

The first one I picked up was a long dbl-slip in an AHM package. It was built by an Italian firm Casadio. It was really quite well built, and considering its long length it should have quite a long gap at the frog that would allow for a lot of wheel drop. But look closely at that metal frog design,..

notice the fatness of the ends of those rails/guard-rails,...combine that with that long pointed frog point means the wheels will be supported over most of the gap.

I thought this comparison between the Casadio on the right with the Roco on the left was interesting,...that little double bulb shape appears again,..

Here is the brass 3 way up recently for auction. Note it appears to have relatively slender frogs, and there may be bulbs there. The controllers appear to indicate they are Casadio brand.

I have a brass double slip by Roco that I intend to use at the trunk of my peninsula. The metal frogs on that turnout appear to be very acceptable,..and compatible with that long Casadio dbl-slip,..

Finally I compare 2 rocos side-by side

Might be difficult to tell from these photos, by that brass dble-slip has a better frog shape than does the 3-way....less flangeway width and longer frog point,...even while there overall size is the same, and they spread the tracks almost identical.


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Casadio 3 ways

Here is the brass 3 way up recently for auction. Note it appears to have relatively slender frogs, and there may be bulbs there. The controllers appear to indicate they are Casadio brand.
I had posted this above. Yesterday I got in the mail 2 of those Casadio 3-ways,....and yes they are brass tracks.
Casadio & Roco next to one another,..

It does appear there is a slight difference in their diverging angles.

Close up photo...

Notice the more narrowness of the frog, and those bulb shapes I pointed out before. Also rather interesting is the full length guard rail,...first time I've seen this. It appears to be approx .010" less wide,...almost like an injected shim.

So I laid a few curve shapes over the two turnouts. The Roco one appears to very close to a 24" radius, while the Casadio appears closer to 29"

There is something I like here,...I believe my long steam engines will like this 3-way just a bit better than the Peco I was planning to put between my turntable and the coaling tower.
with the Casadio turnout laid over the Peco paper template

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