"High speed" turn outs in N

[craigolio1]

Last night I re-read an article in MR on high speed turnouts where the modeller constructs it so that the points are on a central pivot so that not only the points close when you throw the switch, but the wing rails do too which forms a contiguous rail in which ever direction the train is traveling. The idea is to prevent wheels dropping into the enormous gaps we have in our frogs to accommodate our larger than scale wheels and flanges. The article was for HO but I wondered if any of you have tried this in N scale?  I plan to use Fastracks jigs to assemble mine with code 40 rail. I'll be using low profile wheels but not fine scale width treads. My question is do we need this in N scale?  I know with code 40 and low profile wheels you need especially good track work. I plan to use some number tens on my main line. The gap at the frog will be huge. Will my cars' wheels all drop into this gap and cause the train to jiggle or worse as it goes through ?  If so these high speed turnouts would seem the solution but I've never heard of them except in this article.

What are your thoughts?

Craig

[johnhale]

Craig,
   Depends on your purpose.

If you are modeling high speed turnouts so they look like a particular prototype, then it is a good thing. On one of DKS's threads he covers several different turnouts that he has modeled in the past (different wing rails, moving frogs, etc).

If you are concerned about performance, I would say not needed. Keeping stock switches and hand laid switches in gauge is critical to having a train transverse through a turnout.

John

[jagged ben]

I know with code 40 and low profile wheels you need especially good track work. I plan to use some number tens on my main line. The gap at the frog will be huge. Will my cars' wheels all drop into this gap and cause the train to jiggle or worse as it goes through ?

No.  Not if you build them correctly and carefully, and keep your rolling stock wheels in gauge as well.

Study the Fastracks how-to-videos and your NMRA gauge's flanges section for advice on how to make the frogs well.

Echoing John's comments, the high speed turnout thing would be an interesting project if you had a prototype location you wanted to model with true-to-scale turnouts that employed the movable frog.   Even the prototype only does this with very large turnouts, not to mention it's a more modern phenomenon.   If you were building, say, a #16 or larger in N-scale it might be worthy.  With a #10 it's not necessary.   That's a small turnout by prototype standards.

[wcfn100]

Huge gaps at the frog are generally due to construction.   The Point on the frog is one of the harder things to build and keep properly in gauge (along with associated guard rails).  And most frog points are poorly formed and don't come to a true single bevel point.

One of the things you can do is NOT use the Fast Tracks Point Form tool.  While it is possible to get a single bevel point with this tool, you can't do it without removing the rail web and undercutting the rail head (they even talk about it in the video).

There's no reason you would need what your proposing for a #10.  Proper points and an NMRA guage will give you a nice smooth turnout.


Jason

[davefoxx]

If you're using Fast Tracks jigs and templates, you will not end up with huge frogs, as mentioned upthread.  My least favorite commercial frog is on Atlas' curved turnouts.  If you use low profile wheelsets, you can watch the wheels drop into the gap, ride the flanges, and jump back on the rail on the other side of the frog.  The cars didn't derail, because the guardrails did their job properly, but it was annoying to watch trains unprototypically hop through the turnouts.

I just handbuilt a Code 40 #6 turnout a few weeks ago, which was my first in a few years, i.e., I'm out of practice.  That said, there's nary a click through the frog, as trains roll through smoothly.  Try building a standard #10 and see if you're satisfied.  If not, you can then add in the complexity of the movable frog.

Interestingly, my Atlas #5 turnouts are high speed turnouts.   

DFF

[M.C. Fujiwara]

Most of the turnouts on our Free-moN modules are C55 #8 handlaid with a few #7 Atlas (standards call for #6 or higher).
Once in awhile people will run some "high speed" -- Shinkansen or freaky freight -- through the whole layout with nary a bump.
Not sure about C40 but I'm guessing quality turnouts and in-gauge wheels more important than closing the gap.
Would be a cool project to see.

[C855B]

OMG, shades of Tru-Scale! I didn't see the MR article... they may have mentioned them... but 40-some years ago there was a line of HO turnouts that did exactly what was apparently discussed. The points and wing rails were a single assembly that pivoted on a screw in the middle, closing the frog along with the points. They were built that way for operational reliability (supposedly), as that particular mechanical action certainly had no prototype. The reality of using these switches was they were cranky if you weren't diligent about keeping ballast out of the closure areas and making sure the screw didn't back out with use. The club layouts I operated on pretty consistently spiked these closed.

It would be fun to see somebody model a high-speed switch, but like the others have said it certainly wouldn't be for an operational advantage. In fact, it would sort of open you up to a whole new world of adjustment and maintenance. Anyway, a properly designed and built conventional frog should exhibit very little wheel drop, if any.

[craigolio1]

Great.  Less work for me then. Thanks.

Craig