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Turnouts - Shinohara vs. ?

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Posted by Doughless on Saturday, April 23, 2022 8:14 AM

richhotrain

 

 
Doughless

And the differences in the geometry of the two is not great enough to have any bearing on performance of  the two brand of turnouts, to be clear.  I simply see the long loco run through the points differently, and I like the smoothness of the Atlas better, but choose Peco for other reasons.

 

 

That was the point that I was making earlier in this thread. All of this mathematical discussion about the geometry of the turnouts is somewhat interesting, I guess, but it just relates to appearance and does not affect performance. What I fear now is that the next time that I go down to the layout, I will be watching my motive power and rolling stock moving through my Peco turnouts less elegantly than they were before this thread began. Grumpy  Super Angry  Grumpy

 

Rich

 

LOL.  I actually thought about those ramifications before I posted my observations....but then ignored it. Wink

It's exactly what happenened to me the first time I noticed it.  Saw it every time after that.  I resolved the issue by switching to Peco #8's.   Its a new layout and I have the space, so I could do that.  Sorry for bringing it up......

The sometimes too-high pot metal frog on the Atlas I can live with.  If they could simply update the engineering of their points....do something about the rivets which cause the moving rails to be a bit sloppy, and add a spring, I'd prefer the Atlas. 

I think Atlas works well with....maybe even designed for...a switch machine, where I finger flick the points and like the feel of more stability and stay-putedness the Peco offers. 

- Douglas

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Posted by SeeYou190 on Friday, April 22, 2022 10:39 PM

richhotrain
What I fear now is that the next time that I go down to the layout, I will be watching my motive power and rolling stock moving through my Peco turnouts less elegantly than they were before this thread began.

That is a legitimate concern whenever you get any differing opinions about anything you are happy with.

You might love your car, but if you read a few technical reviews on why your model car has shortcomings, you might enjoy it less.

I try not to listen to people pointing out what I am doing wrong, but things still sneek in and irk me.

Less time analyzing, more time running trains, greater happiness.

-Kevin

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Posted by richhotrain on Friday, April 22, 2022 10:35 PM

Doughless

And the differences in the geometry of the two is not great enough to have any bearing on performance of  the two brand of turnouts, to be clear.  I simply see the long loco run through the points differently, and I like the smoothness of the Atlas better, but choose Peco for other reasons.

That was the point that I was making earlier in this thread. All of this mathematical discussion about the geometry of the turnouts is somewhat interesting, I guess, but it just relates to appearance and does not affect performance. What I fear now is that the next time that I go down to the layout, I will be watching my motive power and rolling stock moving through my Peco turnouts less elegantly than they were before this thread began. Grumpy  Super Angry  Grumpy

Rich

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 8:54 PM

Pruitt

 

 
ATLANTIC CENTRAL
I looked uip and printed out the Fast Tracks #6.

6-1/4" lead length......

I will stick with Atlas and build my specials when I need to - without expensive jigs or PC ties.

Sheldon

 

At $15 (or more) savings per turnout, it doesn't take long for the Fast Tracks jigs to pay for themselves. 

 

But there is the time. It takes me about an hour more time to build a Fast Tracks turnout than it would take for me to unpackage and check out a commercial turnout. I figure that's less than a 1% increase in layout construction time over using commercial turnouts. And I'm not dependent on anybody but myself for quality control.

 

Mark, I understand.

I started in this hobby building TruScale switch kits, then learned (was taught by the masters at the Severna Park Model Railroad Club) how to just build them completely from scratch. I built several layouts with all hand layed track and switches.

I still build specials when I need to, but Fast track jigs are of minimal use for that.

I know you and others have all these "quality issues" with Atlas - that has not been my experiance - at least not with the products they have made in the last 20-25 years.

A lot of people will accuse me of living in the past, in this hobby and in other ways. But what I don't do is judge current products based on some experiance from a different product 40 years ago. I have not had any serious quailty issues with Atlas code 83 track, and the few issues that do exist with their product are easily adjusted during installation.

I have MANY friends in this part of the country with basement filling layouts with hundreds of Atlas turnouts that work just fine and have worked for decades.

So it is hard for me to understand some of the problems that people complain about?

And they cost a lot less than PECO and Walthers....

But at this point acquisition cost is not an issue for me, I already have 90% of the 140 turnouts the new layout will require, most purchased a decade or two ago, a fair percentage never installed, still new. The rest salvaged from the last layout because it never reached the "ballast" stage, or they were in staging yards.

But at the end of the day, I simply don't want to spend my time building turnouts, especially since a great number of them will be in hidden staging yards.

The Atlas turnouts that I have bought recently as I stock up for the layout build are just like my older ones and cost on average $20.

Sheldon 

   

    

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Posted by Doughless on Friday, April 22, 2022 8:44 PM

ATLANTIC CENTRAL
The rate of spiral and the minimum radius can all be adjusted to line everything up for a given lead length - within certain obvious limits. The Atlas turnout with its 7" lead, has a dramaticly flater ellipse/spiral that the 6" PECO.

Once again, an elegant description compared to my cumbersome and wordy attempt.

- Douglas

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Posted by Doughless on Friday, April 22, 2022 8:34 PM

ATLANTIC CENTRAL
Exactly! You got it! You sir are a better trackwork engineer than you realize.

Thanks. Conceptually, I understand all of it pretty well...enough to get me to try stuff and then to get into trouble.  Explaining it mathmatically is not my training.

Building a crossover with #6 Atlas turnouts provides a slight easement effect into and out of the crossover.  Its something that I would notice.

Peco would not do that (as much) and I don't know of the new Walthers would do that as much, because their distance from tip to frog looks similar to Peco.  But that would have to be further investigated.

- Douglas

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Posted by Doughless on Friday, April 22, 2022 8:31 PM

ATLANTIC CENTRAL

 

 
Doughless

 

 
richhotrain

Length of Straight Closure Rail:

~ Atlas Custom Line Code 83 #6 turnout - 4.0" (exactly)

~ Peco Code Insulfrog Code 83 #6 turnout - 3.03125" (3 1/32")

Rich

 

 

 

Which figures, because the straight point rails on the Peco are longer than the Atlas, but yet the total distance from point tips to frog is shorter on the Peco.  A shorter stright closure rail and longer point rails add up to shorter distance from tips to frog for the Peco.  And the angle of departure of the point rails are different as well.

So the total curve of the closure rail has to be different.  I contend that the Atlas must have slight easements at either end of its curved closure rail and/or longer straight leading into the frog....what other variable could there be....but I have no way of measuring that.  And my eyeball does not see it, but it sees the gentler departure angle of the point rails.

 

 

 

Using some of my drafting tools, I measured both the actual Atlas turnout, and the PECO drawing.

Both have easements, both are elliptical as I described above.

The PECO is a smaller radius ellipse, as you and I have pointed out, it has to be.

Sitting here looking at the Atlas, a straight edge confirms that the curve goes nearly right up to the frog and right to the point hinge. And several French curves I have suggest that the minimum radius point is at the half way point of the total lead length, with the straight point rail just aproximating the easement curve on the frog end.

Which figures, because the straight point rails on the Peco are longer than the Atlas, but yet the total distance from point tips to frog is shorter on the Peco.  A shorter stright closure rail and longer point rails add up to shorter distance from tips to frog for the Peco.  And the angle of departure of the point rails are different as well.

So the total curve of the closure rail has to be different.  I contend that the Atlas must have slight easements at either end of its curved closure rail and/or longer straight leading into the frog....what other variable could there be....but I have no way of measuring that.  And my eyeball does not see it, but it sees the gentler departure angle of the point rails.

If you blow up the picture in this link, you can clearly see that new PECO Unifrog clearly has a curved diverging point rail.
 
 
And that the sharpest part of the curve is also half way along the lead length, but it is a sharper curve/ellipse.
 
Sheldon
 

Ok that explains it too.  And the differences in the geometry of the two is not great enough to have any bearing on performance of  the two brand of turnouts, to be clear.  I simply see the long loco run through the points differently, and I like the smoothness of the Atlas better, but choose Peco for other reasons.

And now we're introducing a new element of a curved point rail.  Yes, I would say that the new turnouts that have no hinges would tend to have a curved point rail...and springs to hold it in place.  Not sure if the point rail of the Insulfrog is curved compared to the Unifrog...but not wanting to go down that rabbitt hole......

The new Walthers turnout...subject of the OP, may have a curved diverging point rail since I think they do not have hinges.

- Douglas

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 8:25 PM

Doughless

 

 
ATLANTIC CENTRAL
The Peco turnout has a curved diverging point rail (even if it looks straight at first glance), the Atlas diverging point rail is straight.

 

And perhaps this is what I'm noticing when I see my longer cars and locos traverse the Peco.  They move away from tangent quicker.....the closure curve starts sooner, effectively.  Whereas the straight points of the Atlas keeps equipment closer to tangent until it hits the closure rail.  The shallow angled straight point makes an easement effect into the curved closure rail.

Its also why the hinge on the Peco is farther away from the tangent rail.....because the curved diverging point rail continues to move away from tangent as you move up its length. 

The hinge of the Atlas is closer to the tangent rail because the straight rail only moves away from tangent at the constant rate its angle dictates. 

 

Exactly! You got it! You sir are a better trackwork engineer than you realize.

This is one of many reasons why I have lobbied in favor of Atlas for years. 

Or, build your own 7" lead #6's without any fancy jigs...... It's not hard, just time consuming.

Sheldon

    

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 8:18 PM

Colorado Ray

The 3rd PlanIt software includes templates and dimensional information for almost all brands of track.  Trusting that they either measured, or got the information from the manufacturer, I'm going to say that the information is correct.  Here's a comparison of #6 turnouts from Atlas Customline, Peco Insulfrog and FT.

Here's data on the Code 83 Atlas Customline #6

Frog Angle:  9.5 degrees

Normal length (straight) 12"

Routing length (diverging) 10"

Entry to intersection 4-1/32"

Substitution Radius 47"

Rail Closure Radius 48-15/32"

Here's data on the Code 83 Peco Insulfrog #6

Frog Angle:  9.558 degrees

Normal length (straight) 9-3/16"

Routing length (diverging) 9-3/16"

Entry to intersection 3-1/4"

Substitution Radius 37-23/32"

Rail Closure Radius 43"

Here's data on the  FT #6

Frog Angle:  9.527 degrees

Normal length (straight) 9-5/8"

Routing length (diverging) 9-17/32"

Entry to intersection 3-19/32"

Substitution Radius 33-27/32"

Rail Closure Radius 33-27/32"

 

The data supports the information that Douglas has provided.  The Atlas would have the most gradual entry/easement.  I was surprised at how sharp the Rail Closure Radius was for the FT turnout.

 

Ray

 

 

 

Ray, that is interesting and usefull data, but most of it relates to the complete turnout assembly, to the ends of the plastic ties in the case of Atlas and PECO.

Yes the Fast Tracks turnout is sharp.....

Keep in mind that substitution radius is just an approximation of the total diverging route result.

But again, the Atlas wins by a large margin as the most gentle #6 turnout.

They go well with my 36" radius and larger curves..... An Atlas turnout makes a good easement into curves in the 36" to 44" range - the other two, not so much.

But I knew this nearly 4 decades ago.......

Sheldon

    

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Posted by Doughless on Friday, April 22, 2022 8:18 PM

ATLANTIC CENTRAL
The Peco turnout has a curved diverging point rail (even if it looks straight at first glance), the Atlas diverging point rail is straight.

And perhaps this is what I'm noticing when I see my longer cars and locos traverse the Peco.  They move away from tangent quicker.....the closure curve starts sooner, effectively.  Whereas the straight points of the Atlas keeps equipment closer to tangent until it hits the closure rail.  The shallow angled straight point makes an easement effect into the curved closure rail.

Its also why the hinge on the Peco is farther away from the tangent rail.....because the curved diverging point rail continues to move away from tangent as you move up its length. 

The hinge of the Atlas is closer to the tangent rail because the straight rail only moves away from tangent at the constant rate its angle dictates. 

- Douglas

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 8:11 PM

Greg, 

No matter what any historical chart says, all evidence and my own observation shows that closure rails are seldom if ever a constant radius - prototype or model.

I understand exactly what you are saying, but since it is not a constant radius, that simply does not apply. The rate of spiral and the minimum radius can all be adjusted to line everything up for a given lead length - within certain obvious limits.

The Atlas turnout with its 7" lead, has a dramaticly flater ellipse/spiral that the 6" PECO. Anyone should be able to see that just looking at my photo in the early post.

Sheldon 

    

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Posted by Colorado Ray on Friday, April 22, 2022 8:07 PM

The 3rd PlanIt software includes templates and dimensional information for almost all brands of track.  Trusting that they either measured, or got the information from the manufacturer, I'm going to say that the information is correct.  Here's a comparison of #6 turnouts from Atlas Customline, Peco Insulfrog and FT.

Here's data on the Code 83 Atlas Customline #6

Frog Angle:  9.5 degrees

Normal length (straight) 12"

Routing length (diverging) 10"

Entry to intersection 4-1/32"

Substitution Radius 47"

Rail Closure Radius 48-15/32"

Here's data on the Code 83 Peco Insulfrog #6

Frog Angle:  9.558 degrees

Normal length (straight) 9-3/16"

Routing length (diverging) 9-3/16"

Entry to intersection 3-1/4"

Substitution Radius 37-23/32"

Rail Closure Radius 43"

Here's data on the  FT #6

Frog Angle:  9.527 degrees

Normal length (straight) 9-5/8"

Routing length (diverging) 9-17/32"

Entry to intersection 3-19/32"

Substitution Radius 33-27/32"

Rail Closure Radius 33-27/32"

 

The data supports the information that Douglas has provided.  The Atlas would have the most gradual entry/easement.  I was surprised at how sharp the Rail Closure Radius was for the FT turnout.

 

Ray

 

 

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 8:03 PM

Doughless

 

 
gregc

 

 
richhotrain
The straight closure rail on the Atlas turnout is exactly 4.0" in length

 

thanks

but it's the distance from the frog to the points, not to the hinge.  prototypical turnouts don't have hinged closure rails

 

 

 

And the above closure curve begins immediately at the point tips.  On our models, there is about a 2 inch straight section that leads into the curved closure rail when angled.

 

 

All the low frog number prototype turnouts I have ever taken note of have curved diverging point rails. High number turnouts seem to be just the opposite, with long straight point rails.

Sheldon

    

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 7:59 PM

Doughless

 

 
richhotrain

Length of Straight Closure Rail:

~ Atlas Custom Line Code 83 #6 turnout - 4.0" (exactly)

~ Peco Code Insulfrog Code 83 #6 turnout - 3.03125" (3 1/32")

Rich

 

 

 

Which figures, because the straight point rails on the Peco are longer than the Atlas, but yet the total distance from point tips to frog is shorter on the Peco.  A shorter stright closure rail and longer point rails add up to shorter distance from tips to frog for the Peco.  And the angle of departure of the point rails are different as well.

So the total curve of the closure rail has to be different.  I contend that the Atlas must have slight easements at either end of its curved closure rail and/or longer straight leading into the frog....what other variable could there be....but I have no way of measuring that.  And my eyeball does not see it, but it sees the gentler departure angle of the point rails.

 

Using some of my drafting tools, I measured both the actual Atlas turnout, and the PECO drawing.

Both have easements, both are elliptical as I described above.

The PECO is a smaller radius ellipse, as you and I have pointed out, it has to be.

Sitting here looking at the Atlas, a straight edge confirms that the curve goes nearly right up to the frog and right to the point hinge. And several French curves I have suggest that the minimum radius point is at the half way point of the total lead length, with the straight point rail just aproximating the easement curve on the frog end.

Which figures, because the straight point rails on the Peco are longer than the Atlas, but yet the total distance from point tips to frog is shorter on the Peco.  A shorter stright closure rail and longer point rails add up to shorter distance from tips to frog for the Peco.  And the angle of departure of the point rails are different as well.

So the total curve of the closure rail has to be different.  I contend that the Atlas must have slight easements at either end of its curved closure rail and/or longer straight leading into the frog....what other variable could there be....but I have no way of measuring that.  And my eyeball does not see it, but it sees the gentler departure angle of the point rails.

If you blow up the picture in this link, you can clearly see that new PECO Unifrog clearly has a curved diverging point rail.
 
 
And that the sharpest part of the curve is also half way along the lead length, but it is a sharper curve/ellipse.
 
Sheldon

    

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Posted by Doughless on Friday, April 22, 2022 7:45 PM

gregc

 

 
richhotrain
The straight closure rail on the Atlas turnout is exactly 4.0" in length

 

thanks

but it's the distance from the frog to the points, not to the hinge.  prototypical turnouts don't have hinged closure rails

 

And the above closure curve begins immediately at the point tips.  On our models, there is typically about a 2 inch straight section that leads into the curved closure rail when angled.

 

- Douglas

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Posted by Doughless on Friday, April 22, 2022 7:36 PM

richhotrain

Length of Straight Closure Rail:

~ Atlas Custom Line Code 83 #6 turnout - 4.0" (exactly)

~ Peco Code Insulfrog Code 83 #6 turnout - 3.03125" (3 1/32")

Rich

 

Which figures, because the straight point rails on the Peco are longer than the Atlas, but yet the total distance from point tips to frog is shorter on the Peco.  A shorter stright closure rail and longer point rails add up to shorter distance from tips to frog for the Peco.  And the angle of departure of the point rails are different as well.

 IMO, the only way that there could be longer point rail, a shorter closure rail, and shorter total distance from tip to frog is if that point tip meets the diverging rail sooner with the Peco than it does with Atlas.  If the diverging stock rail of the Atlas has a slight easement near the tip, the rail will never quite meet the tip unless more length is added.  And if there is an easement near the tip, the Atlas needs to have its other point rail depart gentler in order to keep the rails in gauge.

Edit: Sheldon points out the the diverging point rail of the Peco is slightly curved whereas the Atlas is straight.  This would certainly explain pretty much everything I'm seeing, but way simpler.

- Douglas

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Posted by gregc on Friday, April 22, 2022 7:00 PM

ATLANTIC CENTRAL
This is why Greg's drawing of various length turnouts with the same frog angle is not correct - he used constant radius curves and added more straight rail near the frog.

the diagrams illustrates the maximum possible radius with the given lead-length, not how model turnouts are actually made.

the closure curve cannot be replaced with a larger constant radius curve and still have it align with the frog.   the smaller the lead-length, the tigher the radius and the curve reaches the frog angle further from the frog requiring the straight section

if any section of the closure rail curve is made a larger radius, the remainder of the curve must be tighter to remain aligned with the frog.   

(think about what happens to the other part of the closure rail aligned with the frog if one part is made straighter).

these values are consistent with the numbers and calculations posted on the Catskill Archive - Frogs and Switches

greg - Philadelphia & Reading / Reading

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Posted by SeeYou190 on Friday, April 22, 2022 6:42 PM

Pruitt
I'm not dependent on anybody but myself for quality control.

That is a great advantage.

-Kevin

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Posted by Pruitt on Friday, April 22, 2022 6:38 PM

ATLANTIC CENTRAL
I looked uip and printed out the Fast Tracks #6.

6-1/4" lead length......

I will stick with Atlas and build my specials when I need to - without expensive jigs or PC ties.

Sheldon

At $15 (or more) savings per turnout, it doesn't take long for the Fast Tracks jigs to pay for themselves. 

But there is the time. It takes me about an hour more time to build a Fast Tracks turnout than it would take for me to unpackage and check out a commercial turnout. I figure that's less than a 1% increase in layout construction time over using commercial turnouts. And I'm not dependent on anybody but myself for quality control.

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 5:56 PM

I looked uip and printed out the Fast Tracks #6.

6-1/4" lead length......

I will stick with Atlas and build my specials when I need to - without expensive jigs or PC ties.

Sheldon

    

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 4:43 PM

gregc

why does it matter?

the actual length of the turnout doesn't determine how well cars or locomotives track through it. as Sheldon has said, "shorter point to frog dimension means a sharper closure radius".   a longer lead-length also allows for easements as Douglas mentioned

so two brands of turnouts may both be #6, but one may have problems with longer wheelbase locos, even though its total length is longer while another does not.

 

Correct! 

In fact nearly all US protoype turnouts with straight frogs have closure rails that are effectively an elliptical curve with and easment into them at the points and out of them at frog.

They are NOT a constant radius.

This is why Greg's drawing of various length turnouts with the same frog angle is not correct - he used constant radius curves and added more straight rail near the frog.

Again, while it cannot be seen in the photo, it is clear the PECO turnout has a sharper "ellipse" for a closure radius. Obviously the rails need to end up in the same places, but mid way in the curve, the PECO bulges out - again, nearly 1/8".

It is that vertex of the ellipse that will be the smallest radius, and the effects of truck swivel and coupler travel come into play.

Now here is some food for thought - the nice people at Atlas designed this geometry for their #6 Custom Line turnout sometime in the 1950's. While the product has been improved, offered now in code 83, had metal frogs added, the geometry has NEVER been changed since the first code 100 plastic tie Custom Line turnout was offered. Pretty smart guys in my book.

Sheldon

 

    

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 4:03 PM

So, I don't have any PECO turnouts to look at here, but the nice people at PECO have these nice scale drawings online.

And drafting and engineering are my first skills.......

So here is an Atlas #6 layed on top the PECO drawing which scaled out perfectly based on the scale printed on the the drawing.

As I explained before, the PECO has a shorter lead length and thereby a sharper closure radius - however slight.

The PECO has a lead length of 6", that is frog tip to points. The Atlas measures a whole inch longer at 7".

A product photo of PECO SL-U8362 on the Yankee Dabbler web site also clearly confirms what I said before, the diverging point rail is curved. You can see in my photo the Atlas is clearly straight.

 

The frog angles match up close enough and the diverging routes end at the same location relative to the rog, so both turnouts will make crossovers with 2" track centers.

You cannot see this in the photo, but if you look carefully thru the Atlas switch laying on the drawing, you can see where the closure rail of the PECO does not exactly line up and its sharper radius offsets it almost an 1/8".

So yes, for the 300th time, the PECO is more compact because it has a sharper closure radius.

If you are using 30" curves and you stuff runs on 30" curves, then this small difference is not of much concern.

If you have larger curves, the Atlas may be more in line with the geometry of your curves.

I can assure you that 80' cars going thru a crossover will look better with the Atlas product. And given the complaints I read on hear about RTR passenger car derailments, I would be inclined to think Atlas would be better for that reason as well.

Once again, the Atlas #6 is longer, more gentle than NMRA RP dimensions. And the Atlas "#4" is really 12.5 degree #4.5.

There is no free lunch in physics or geometry........

Remember, that scaled down from the prototype, a 36" radius curve would be the sharpest curve a Big Boy or an 80' passenger car could squeek around at 10 mph..... and a #6 turmout would likely put both on the ground.

Sheldon

    

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Posted by gregc on Friday, April 22, 2022 3:59 PM

why does it matter?

the actual length of the turnout doesn't determine how well cars or locomotives track through it. as Sheldon has said, "shorter point to frog dimension means a sharper closure radius".   a longer lead-length also allows for easements as Douglas mentioned

so two brands of turnouts may both be #6, but one may have problems with longer wheelbase locos, even though its total length is longer while another does not.

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Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 2:23 PM

SeeYou190

 

 
riogrande5761
Fast tracks sounds great, but it requires TIME.  Nice for those who have hobby time.  A layout take a lot of time as it is.

 

I prefer to spend my hobby time not building turnouts.

I do prefer detail painting. That takes time, and I suspect most other modelers prefer to spend time not detail painting.

Do with your time that which you enjoy.

Shinohara turnouts and Atlas track work for me.

-Kevin

 

I agree, I am way past the point where I want to scratch build turnouts.

I build the ones I can't buy, and have even learned how to curve Atlas regular turnouts into very large radius curved turnouts.

I have watched others use FastTracks, and the only advantage I see over how I was taught to scratch build them is higher uniformity - you know like just buying them factory made.....

I'm starting a layout with 140 turnouts, I already have nearly all of them I need.

Sheldon

    

  • Member since
    January 2017
  • From: Southern Florida Gulf Coast
  • 18,255 posts
Posted by SeeYou190 on Friday, April 22, 2022 12:50 PM

riogrande5761
Fast tracks sounds great, but it requires TIME.  Nice for those who have hobby time.  A layout take a lot of time as it is.

I prefer to spend my hobby time not building turnouts.

I do prefer detail painting. That takes time, and I suspect most other modelers prefer to spend time not detail painting.

Do with your time that which you enjoy.

Shinohara turnouts and Atlas track work for me.

-Kevin

Living the dream.

  • Member since
    July 2009
  • From: lavale, md
  • 4,678 posts
Posted by gregc on Friday, April 22, 2022 10:48 AM

ATLANTIC CENTRAL
There are prototype turnouts with and without hinged points.

thanks for making me aware of this.

greg - Philadelphia & Reading / Reading

  • Member since
    January 2009
  • From: Maryland
  • 12,897 posts
Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 10:39 AM

Greg,

There are prototype turnouts with and without hinged points.

The nature of the materials suggests that the closure rail will flex right at the spot where it is no longer fastened down to the ties. And if that is a fishplate joint, it will behave much like our model track at a kinked rail joint - that is a defacto hinge.

Sheldon

    

  • Member since
    July 2006
  • From: west coast
  • 7,667 posts
Posted by rrebell on Friday, April 22, 2022 10:34 AM

gregc

 

 
richhotrain
The straight closure rail on the Atlas turnout is exactly 4.0" in length

 

thanks

but it's the distance from the frog to the points, not to the hinge.  prototypical turnouts don't have hinged closure rails

 

That may be true but I bet some have been built, I know there is a patent out there for one.

  • Member since
    July 2009
  • From: lavale, md
  • 4,678 posts
Posted by gregc on Friday, April 22, 2022 10:30 AM

ATLANTIC CENTRAL
You can't work from the points, you have to work backward from the frog. A shorter point to frog dimension means a sharper closure radius - period. For any given frog angle there is a range of point to frog lengths that will work, longer means larger closure radius - up to the limit of the geometry established by the frog angle.

don't know what i've said that disagrees with this.

greg - Philadelphia & Reading / Reading

  • Member since
    January 2009
  • From: Maryland
  • 12,897 posts
Posted by ATLANTIC CENTRAL on Friday, April 22, 2022 10:26 AM

We have been thru this turnout dimension thing so many times......

The Peco turnout has less track before the points and after the frog on the straight thru route.

The Peco turnout has a slightly shorter length from point tip to frog ( lead length), resulting in a slightly sharper closure rail radius.

The Peco turnout has a curved diverging point rail (even if it looks straight at first glance), the Atlas diverging point rail is straight.

The Atlas point to frog dimension is longer than NMRA RP, the Atlas turnout has a more gradual departure, and thereby a slightly larger substitution radius and closure radius.

If you really need or want to pack them in tighter, the Atlas can be trimmed.....

The frog angles are the same.

Greg, I have already explained to you several times the flaws in your one diagram......

You can't work from the points, you have to work backward from the frog. A shorter point to frog dimension means a sharper closure radius - period. For any given frog angle there is a range of point to frog lengths that will work, longer means larger closure radius - up to the limit of the geometry established by the frog angle.

I've built my own turnouts, without FastTracks, and used every brand on layouts I have built or helped others build.

My choice is still Atlas, electrically and for geometry.

All these differences are VERY small.............

The Peco turnout only makes a more compact crossover by virtue of the shorter lead length and the shorter track length past the points.

The Peco turnout does not make 2" track center diverging routes for yard ladders,, it needs small spacer tracks. That is why the Atlas has the longer straight route, to make 2" center yard leads.

By design, the Atlas turnout discourages placing curves too close to the points or frog, which can often be a source of problems, especially for those who insist on smaller radius curves.

Sheldon

    

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