#8 versus #12 turnouts

[BigRusty]

I think that the best place for #12 turnouts is for high speed crossovers or passing sidings, if you will have them. I am using #8s, for which I bought the Fast Tacks fixture, and for spurs, Peco #6s.

[reklein]

I looked at the Fast Tracks site and decided that its more than I WANT to pay. My layouts trackwork is pretty well finished. Were I starting anew I would definitly consider Fast Tracks. Maybe my next layout. Filing down the frog tops has helped immensly and I've some other problems involving grade changes under the turnout that I thought I could get away with.

[Lillen]

I guess you guys are right. I will stick to the #8's instead of this. I will probably order one of those jigs soon. I'll see when I get around to it.

 

Thanks for all of your input, that saved me from perhaps a mistake in the 200$ department.

 Happy new years everyone!

Magnus

[cuyama]

Remember that the # of a turnout only indicates the ratio of separation. A little research will show that CVT #9's have a longer point to frog length, hence a larger, smoother radius for longer cars, than Wally's #10's even though there is a little more angle to them.

John makes an excellent point. This dimension is called the lead length. Making this dimension longer may have more impact on model operations than does a small increase in the frog number. I believe that Fast Tracks templates are generally derived from the NMRA turnout Recommended Practices (click here for the HO RP), which have a relatively short lead length (Dimension #8 in the RP). For this reason, many experienced modelers prefer to build their own turnouts to fit the situation, often with longer leads, than to use templates.

In a typical model railroad space in HO, common use of #12s everywhere on the mainline will probably require a lot more room than one realizes at first glance -- especially when one considers crossovers (twice the length) and the need to have straight sections in some locations between curves and turnouts diverging in the opposite direction to elminate s-curves. 

For my money (and space), easemented curves will probably provide more operating benefit than a change from #8 to #12 within the typical model railroad space constraints. Next, if I was planning to hand-lay, I'd consider building #8 turnouts with longer leads than the NMRA RP. Then if there was still extra space, I'd look at increasing the frog number.

But of course, even then, the overall benefit of that increase in frog number is probably appearance, not operation. The reason being that the minimum radius of the curves in a typical layout space will likely become the determining factor in how well large equipment operates, not the difference between a #8 and a #12 frog.

Byron
Model RR Blog

[selector]

John, every turnout will let the wheel down between the elbows of the wing rails and the frog point, no matter how long the frog is, unless the filler that the commercial turnout manufacturers use to support the flanges at the correct height prevent it.  It is the next half-length of the wing rail, after the elbow, that supports the prototype's passage across the frog gap, and it works precisely the same way in Fast Tracks turnouts.  So, Fast Tracks turnouts don't get the molten whatever-it-is filler since it is not needed. 

Furthermore, if the NMRA flange gauge can pass between the two wing elbows, across the gap, and then through the rest of the frog, there must of necessity be a sufficient gap across the wing elbows and the frog point to allow the wheels to at least do a good dance in the gap.  If the long or short frog point position won't allow the flange gauge tips to pass unhindered through the frog, you have an alignment problem and the rolling items will pick the frog point and derail...so there must logically be a minimum separation between the frog point and the wing elbows to keep a sufficient clearance for the flanges to pass in their channel.  This, again of necessity, requires there to be a distance between elbow and frog point sufficient for the wheels to fall through into the gap...unless supported by fill.  Once again, in the Fast Tracks case (and not in the Central Valley case where the frog is a solid metal shaped block), the idea is to conform to the prototype's expectation and intent and let the wing rails do the job.  Tim Warris demonstrates this most convincingly in his construction video on his site, and it is the reason that Fast Tracks has begun to get such a good head of steam...they have properly engineered turnouts.

-Crandell

[Lillen]

I use #10 almost all over my layout. I don't use anything lower then a #8. I have 1 number 12 turnout. I had it made for me. The #12's look out of place unless you have huge amounts of space. The #10's are boarderline. I use the #10's because I have several brass UP 4-12-2's and they need them. Do you understand how big a #12 really is??? But to answer your question, no there is no advantage to a number 10 to a number 12. There isn't a engine made that will not go through a #10 smoothly.

 

I realize that they are huge. That is why I'm only considering them for the mainline on places where space isn't much of an issue, For example on a 8 meter long straight with only one mainline turnout.

 

According to fast tracks website the #8's are

Default Turnout Length

14.7" (373 mm)

 

and the #12's are:

Default Turnout Length

19" (483 mm)

 

Which for me is acceptable on a few well chosen turnouts. That's only 11 cm more. Ofcourse in a yard that would be unacceptable. But you might be right. That is why I'm asking. So far I have used nothing but #8's and should perhaps stick to those. The number 10 is only 6 cm longer then the  #8's. So what do you think of those? Would they be more suitable.

 

I should perhaps ad that I like large engines like Big boys and the likes and I love 85 foot passenger cars. Those are the things I want t look nice when I run them.

 

Do anyone have a picture with a #8,10 and 12 respectively next to each other?

 

Thanks for all your help.

 

Magnus

[johncolley]

Remember that the # of a turnout only indicates the ratio of separation. A little research will show that CVT #9's have a longer point to frog length, hence a larger, smoother radius for longer cars, than Wally's #10's even though there is a little more angle to them. They are beautiful with 85 foot streamliner cars, and one can even back a train over a crossover made of #9's if needed! Yours for big curves and turnouts, They are why I went over to Free-mo Modular Railroading. jc5729 John Colley, Port Townsend, WA

[selector]

Magnus and reklein, the longer the frog (the longer the turnout) the better the geometry for the wheel to ride on the wing rails on either side of the frog point if the gauge is correct and strictly abiding by the NMRA standards, as the Fast Tracks turnouts do.  It is the commercial turnouts that fail, although they should improve the longer the turnout....you'd think.

I use #8 turnouts that run about 12" (30 cm) on my main.  They are wonderful and smooth.  #10 or #12 would be quite a bit longer.  If you have the room, use them.  If you would like their advantages, but are a bit tight on the ideal track plan, used curved turnouts.

-Crandell

[riogrande5761]

For you guys with the #10s. Hows the wheel drop at the frogs. Seems like one would have to be pretty careful with frog construction. I agree though the looks and reliability of the #8s sure seem to help although they do take up a lot of room.

Good point since there was a topic on the Atlas #6 having the "pot holes".  The longer the turnout, the more potential there is for this.

(glad to see the mods keeping things cleaned up around here!  good job!)

[reklein]

For you guys with the #10s. Hows the wheel drop at the frogs. Seems like one would have to be pretty careful with frog construction. I agree though the looks and reliability of the #8s sure seem to help although they do take up a lot of room.

[Marc_Magnus]

Hi

First I use Fast Tracks jigs and I highly recommend them for the quality of turnout you can scratchbuild ( I use Nscale) I use number 8 for mainline, 6 for siding and yard and 8 for curved turnout, all build from Fastrack system.

Second, if yo have the space use big turnouts like a 12 or a 10 frog number.

Generally modelers use  something around a 8 for mainline purposes and a 6 for siding and yard.

You can print template of each turnout on the Fastrack site and see if they could accomodate your space layout.

[riogrande5761]

Hi,

I've as I said been thinking about ordering some fast track jigs. Now my question is this. How much operational benefits would you get out of using #12 instead of #8 turnouts on the mainline. I love the looks of long turnouts and on long mainlines I don't think that the extra space is that much of a problem. The looks are a  lot better but how much is the effect on reliability?

Magnus

I honestly have never used #12, and I would wager 98% of modelers on this forum don't either, so lets hope you get lucky and have some first hand experience here to respond!

However, I would say that for reliablility, track work quality and your rolling stock tuning (wheels in gauge and proper weight) is going to have a far bigger effect on reliability than a longer turnout would on a model RR.

If you like the looks of a #12 and have the room, just go for it.  I plan on using #8 turnouts for mainline sidings and #6 in yards for a good compromise between, looks and reliability and space considerations.  I have a bunch of #8 curved turnouts already, and wish there were larger for curved - those are 32/36-inch radii inside and out.  They should handle 99% of rolling stock in HO.

[Lillen]

Hi,

 

I've as I said been thinking about ordering some fast track jigs. Now my question is this. How much operational benefits would you get out of using #12 instead of #8 turnouts on the mainline. I love the looks of long turnouts and on long mainlines I don't think that the extra space is that much of a problem. The looks are a  lot better but how much is the effect on reliability?

 

Magnus