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RailKing50
24th Mar 2023, 01:55 PM
Calling all of you track laying experts......

I am laying out a module where there will be a section of Nn3 trackage and third rail track. At some point, the Nn3 track must connect with the third rail track. So which brings me to the reason for posting here.... I am fairly confident that I can manage the third rail straight track section, the switch on the other hand, not so much.

My hobby time is limited now-a-days, so I do not want to delve into making my own turnouts at this time. My initial thought was purchasing a Z scale switch and then modifying it to add the third rail.

Below is the switch that I am needing to recreate.

Any thoughts/comments/concerns from the collective?


129677

WP&P
24th Mar 2023, 05:38 PM
Well what you have isn't really a switch per se, since each route only has one option. It's more like a crossing in some ways, which leads me to a supposition. On the real railroad, it appears they did treat it as a switch and have one operable point rail. I would bet, though, that you could get by with just a frog and a permanent gap where the point rail would be, the way diamond crossings are made. The curve of the opposite narrow gauge stock rail will force the narrow gauge flanges one way, while standard gauge must follow the other rail, just the way that frogs and guardrails normally work.

I could see this being a case where a stub switch would make sense... one rail that is left loose enough to bend between the two route options. Might have been done in the real world, too. You would just need to solder the rail to a throwbar, then put in some form of stops to limit the throwbar travel, and maybe an over-center spring. All could be done as modifications to regular plastic-tie track, meaning you could afford to even practice and try again if you flub it up. Could be a good skill-building exercise.

ChicagoNW
24th Mar 2023, 06:42 PM
As WP&P said, that isn’t a switch so why bother with one. Why not harvest a curved rail from a piece of Z sectional and build what you feel comfortable, the dual gauge straights. At the crossing track attach the curved rail to a Standard grade section and just cut gaps for the flanges. No need for a frog, which will add electrical problems. If you feel insecure, add some small guard rails that don’t contact anything or even make them from plastic. Here’s the ones on a Tomix Mini Fine Track turnout…
https://www.nscale.net/forums/attachment.php?attachmentid=129678&d=1679697532

el Gato Gordo
24th Mar 2023, 08:02 PM
I agree with the two comments above. It's not a turnout, so replicating it should not be difficult. (Says the guy who has never built track....)

The Ol' Curmudgeon
24th Mar 2023, 08:24 PM
Calling all of you track laying experts......

I am laying out a module where there will be a section of Nn3 trackage and third rail track. At some point, the Nn3 track must connect with the third rail track. So which brings me to the reason for posting here.... I am fairly confident that I can manage the third rail straight track section, the switch on the other hand, not so much.

My hobby time is limited now-a-days, so I do not want to delve into making my own turnouts at this time. My initial thought was purchasing a Z scale switch and then modifying it to add the third rail.

Below is the switch that I am needing to recreate.

Any thoughts/comments/concerns from the collective?


129677

The late John Armstrong, an expert in nearly all matter railroading and a well-known modeler, termed this a "transportation switch," and included one or two in one his published track plans that featured standard gauge and narrow railroads sharing engine terminal trackage. It has a frog and one point.

Sumner
24th Mar 2023, 08:25 PM
It isn't a turnout but I feel you need turnout building skills to build it. Basically it is a turnout minus one point so you still need to build the frog and one point that moves. Not real hard but something someone might not want to do on their first go at hand-laying track. There is a member here that I know could do it, not sure what he would charge but if he doesn't contact you PM me for a name and no it isn't me :).

Sumner

RailKing50
24th Mar 2023, 09:41 PM
termed this a "transportation switch,"

That term fits better. I called it a switch because it has moving parts, so thanks for ed-u-ma-cating me.

RailKing50
28th Mar 2023, 11:37 AM
At the crossing track attach the curved rail to a Standard grade section and just cut gaps for the flanges. No need for a frog, which will add electrical problems.
No electrical problems is would be a plus.



that you could get by with just a frog and a permanent gap where the point rail would be
I am not opposed to using my modeler's license and going this route. I could add the detail pieces to simulate the ground throws running to the station.

Comfortably numb
28th Mar 2023, 03:24 PM
What code of rail are you using?

What radios of curve out is it to be?

How long is the run out at each end?

I think I have an Idea of what you are needing and I would like to build this.

If I know this info I can estimate the cost.

Tim R
28th Mar 2023, 03:53 PM
Building it with a moveable point has the advantage to being able to use some sort of switch machine to control polarity for the frog. The downside is it's got to be lined properly or things go bang.

Without moveable point means using a frog juicer or dead frog. The advantage is the trains will always go the right way.

As WP&P mentioned, you could make it with a gap where the point should be. The standard gauge route should have a guardrail to keep the standard gauge wheel sets going down the right path. I've seen this called a gauge separation turnout.

Comfortably numb
28th Mar 2023, 06:20 PM
129711 Is this what you needed?

Stu
28th Mar 2023, 07:51 PM
Nice idea, CN. Would it be helpful to have the guard rail for the bottom (mainline) stock rail go a bit further to the left?

Sumner
28th Mar 2023, 08:09 PM
https://www.nscale.net/forums/attachment.php?attachmentid=129711&d=1680042003

That would work but if it was mine I would still use a point rail like in the image at the beginning of the post and switch it. That would avoid that long gap that a wheel is going to drop in since it is quite a bit longer than the one at the frog. A loco or car would probably make it past but I like the idea of a point rail and having to also set it to the route. You could then also get rid of the the bottom guard rail to the left and some of the first guard rail leading off to the top.

Sumner

ChicagoNW
29th Mar 2023, 05:41 PM
Other than using overhead wire, how are model trains going to get through that junction? There seems to be awfully large dead rails used. If using DCC, isn’t an auto-reverser required? Is it even possible to use this with rail powered DC? As I see it, this junction works perfectly with internally powered trains using pizza cutters.

As a traction modeler (we use single point turnouts) I don’t see the need for a point rail. This special track doesn’t act like a switch. It’s two separate rail lines using the same ties and a rail. Neither train can access the other’s route. Just like a gauntlet track using a narrow bridge. Each of the two tracks sharing the single set of ties, go their separate ways, once they cross the bridge. While the junction uses frogs they don’t use points. You wouldn’t use any on a 5° crossing, would you?

A moving point rail could easily derail either route if left in the wrong position. A spring powered point would always deny the one route. It works in one direction only. They work best in N scale with pizza cutters.

A question for you rail slingers, what if you designed this junction using the other standard gauge rail as the common one. Would that make it work better, either electrically or mechanically?

While the so called “pizza cutter” flange wheels are often derided. That tall flange often kept wheels from falling off the rails in such large gaps as you guys are suggesting. They also helped guide the wheels giving the wheels a larger diameter, allowing them to using the frogs as rails. Collecting power while the tread was riding on air.

What is the radius of the narrow gauge track or at what angle do the two tracks intersect?

Comfortably numb
29th Mar 2023, 08:45 PM
That drawing is just for concept not to scale. In the picture the inner rail is common running , narrow gage is left hand running here. the only reason for a point in this case would be, to make the train stop and manually switch to proceed. so if we do it that way you could have singles and power frogs. if we build it like a gantlet , the frog can be built with short or closes gapes. then Gard rails will be a must. In N scale they tend to be bigger that 1:1 .

Sumner
29th Mar 2023, 08:52 PM
https://1fatgmc.com/RailRoad/RR-misc/23-03-29%20N%20Gauge-1.jpg

Above is what was posted at the beginning of the thread and what I think I see. I'd build it like that. Of course there is usually more than one way to do something ;).

I'd handle the frog polarity like I do on my turnouts. Use a SPDT limit switch on the switch machine or on the switch machine control or a frog juicer from Tam Valley. The first two work fine for DC or DCC. Tam Valley's frog juicer is only for DCC.

Sumner

Comfortably numb
30th Mar 2023, 12:03 AM
129720 Im going to use the #5 jig. from fast tracks. 129721 made this long so I can put supports on the ends. 129722 129723 set the Nscale part on the point end. 129724 now I'm starting on the Nn3 rail. 129725 From what I found 6.6mm is the scale for this part. 129726 the inspector stopped me and said it was all wrong... 129727 129728 so I ripped out the rail in the center and shortened it. 129729 This is the Gantlet version. I will work on the point version tomorrow. I still need to figure out the gaps and the point tie bar. I think its going to have to be the wide one.

So is this any thing close ?

RailKing50
30th Mar 2023, 06:20 AM
So is this any thing close ?

Yessir! I appreciate you working on this.

ChicagoNW
30th Mar 2023, 08:16 AM
Here’s how it’s done in HO with Tillig track
https://www.tillig.com/eng/Nenngroesse_H0e_Gleissysteme.html

Here’s a clearer shot where there is a switch
https://upload.wikimedia.org/wikipedia/commons/f/fb/Switch-bifurcation_of_dual_gauge_rail_near_Jindrichuv_Hra dec.jpg

Comfortably numb
30th Mar 2023, 02:02 PM
Here’s a clearer shot where there is a switch
https://upload.wikimedia.org/wikiped...huv_Hradec.jpg



Thanks that shows me what I was needing.

Comfortably numb
30th Mar 2023, 05:43 PM
129744 This is to short of rail to bend . 129745 So I built it as a hinge point. 129746 129747 and the standard tie bar was to small. 129748 129749 So I used the wide through bar, this gives better hold for the rail to the through bar .

Comfortably numb
30th Mar 2023, 08:08 PM
129753 129754 OK... Is this what you wanted? The ties at each end are just for shipping. I made them long so it could be cut to fit. I just need to make wood ties and frog power lead.

Sumner
30th Mar 2023, 10:24 PM
Great work. If I was building it that would be exactly how I would build it also. Looks pretty cool...

Sumner

Comfortably numb
30th Mar 2023, 11:47 PM
129755 I'm calling it finished.

RailKing50
31st Mar 2023, 06:25 AM
That looks phenomenal!

el Gato Gordo
31st Mar 2023, 07:57 AM
What RailKing50 said! Great job, Comfortably numb.

Comfortably numb
3rd Apr 2023, 06:04 PM
Shipped out today. 9516 4140 1777 3093 6577 75 USPS.

RailKing50
4th Apr 2023, 08:10 AM
Can't wait! Thanks again Comfortably numb !

What I was thinking was going to be the hardest part of the module turns out to be the first piece "complete".
I'll be starting a separate thread for pictures when I have something far enough along worth sharing.

Comfortably numb
8th Apr 2023, 05:43 PM
Did you get it ?

RailKing50
21st Sep 2023, 08:50 AM
We have a show coming up this weekend, so I took a pause from working on my Double Track BendTrack modules and focused on my single track BendTrack module to take it from ideas to an operable module.

Our version of BendTrack requires KATO Unitrack for the mainlines, but for the Single Track Branch Lines, only the ends need to be Unitrack compatible.

So, I used 2x sticks of Atlas code 55 rail, 1x Atlas LH turnout, and the diverging Nn3 route switch that Comfortably numb made for me and went to work.

The conversion from Unitrack to Atlas code 55 was achieved by flattening the code 80 track joiners and the code 55 rail sitting on top of them which were then soldered in place. Went a lot smoother then anticipated. It looked cleaner until I added the track feeders to the joint. :-/

131031

The 12" of third rail was "track spiked" in place. I may end up super gluing it in place at a later date. I just wanted to get this module in operable condition for the weekend show.

Shame on me for not getting a better overall picture last night. The B&O diesel is actually sitting on the standard gauge siding and the white rectangle is going to be the station.

I gave myself enough of a lead where I'll be able to move a car in and out of the siding when this is a standalone module.

OR&W Combine 29 and caboose can be seen occupying the Narrow Gauge mainline in the center of this picture.

131032