Another Minumum Radius question. N scale

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Bushel86

Active Member
So While I am Building my Large N scale switching layout. after starting a new from Ho scale. I decided I want to Build a Test Layout, This layout is to serve 3 Major factors..

1.) It will be my Dcc Programming Track.
2.) Must be used to Break in locomotives,
3.) Layout will be used to test new scenery ideas and techniques before applying to main layout.

While This Layout also has to Be Small, and be able to be stored when Not in use. It will not be part of a bigger layout or be used for anything other than breaking locomotives in and programming them.. What I need to know. Since I do not own or plan to own in the for seeable future Modern Large diesels, is What is the minimum radius I can use for every Large Diesel loco? I do not plan on doing any steam.

I had Plan on using 12" radius as my minimum. If I can sqeeze it down to 11 That be better.

I do not care about how silly the loco looks, Thats not what this Layout is about.
I also Agree Bigger radius is Better, But Again, this is not a show layout or to be used for such.. And so I am not trying to make it as such.

I really Just need those of you who have large modern Diesels to Just help me know what I can get away with without binding the trucks. because I do not own any myself But want to plan ahead for such if I ever get the itch too.

While my main layout is Focused on Lance mindheim point to point Operations, This test layout I want to be able to accomadate for modern diesels if my desire changes for my main layout. therefore I already have something I can use to Break in and Program new locomotives without having to use the main layout.. and If I can fit this layout into a closet when Not in use that will be even better.

Once you can help guide me to a certian radius, I can then choose the size of the layout, and for me the smaller the better, simply for storage reasons.

Also I should mention I do not plan on pulling any cars with these large Locos, If I do make the layout more display like I use small power for it. But to break in a Big Loco its just be light power to break in the motor. So having said that. If I can keep the benchwork at 24x48" for this layout I would prefer that.. other wise if I stay with 12" radius I will have to Go a bit wider and the wider it becomes the harder storage becomes..

Thanks for any and all help.
 
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I have some N scale stuff, the mfg's says 9 3/4” minimum but 11” is recommended.
So I looked at Atlas, Intermountain, Scale Trains, Kato etc. websites and they say the same.
I think that’s kind of standard, but most folks here will say and as you mentioned go as big as your space allows.
 
Rico said:
I have some N scale stuff, the mfg's says 9 3/4” minimum but 11” is recommended.
So I looked at Atlas, Intermountain, Scale Trains, Kato etc. websites and they say the same.
I think that’s kind of standard, but most folks here will say and as you mentioned go as big as your space allows.
Click to expand...
The Problem Is I don't trust the Mfg Stats, I rather have real world knowledge of what people actually have found out for themselves. That's why I don't just go by the MFG. And if I have to do anything to the loco to make it run on that tight of a radius its not really worth it. since my main layout won't have that tight of a radius to begin with. So I just want to be safe with making sure the curve is broad enough for everything But minimum enough to be stored without to much space being used... So Thats why I was thinking 12" radius for the layout. I can make the layout 26" deep and it can still be stored in my hobby rooms closet without issues.

While My main layout will have minimum of 18" radius. Its no problem for anything on the main layout. But this layout will also scratch the itch of continous running without me needing to incorparate it into my main layout.
 


12" should be fine for almost any diesel you are considering using. The only ones you may have an issue with are some larger brass diesels.
The only ones I've had an issue with are pulling cars when coupled to the front of Kato PAs and SD40-2s. The engines themselves are okay, they just tend to pull the truck of the first car off the rails on some curves.
 
bnsf971 said:
12" should be fine for almost any diesel you are considering using. The only ones you may have an issue with are some larger brass diesels.
The only ones I've had an issue with are pulling cars when coupled to the front of Kato PAs and SD40-2s. The engines themselves are okay, they just tend to pull the truck of the first car off the rails on some curves.
Click to expand...
Thanks. I Don't ever plan on doing Brass. at least not in N scale. And I figured That 12" would be good enough for what I was going to use it for. Since they won't be coupled to cars most likely. But again I am not planning on using Anything Big since my plan for my main layout is to model an industrial branch line. But that could change. So i just want to be prepared.

Appreciate it.
 
I had a friend in our N-scale club that built his first layout using 9-3/4" radius curves. Fine for his 4-axle locos, but he had a few 6-axle locos that wouldn't run on it. Too tight of a radius, of course. He built another small layout later on with 11" radius curves, and had no further problems with 6-axle diesels running on it.

So 12" radius should be just fine. I would also recommend a figure "8" layout for break-in purposes, not only to help exercise the trucks in both directions, but also to diagnose possible electrical connection problems in the loco. For instance, I have seen more than one loco do just fine running laps in a clockwise direction around an oval, but stall out or quit running all together going in a counter-clockwise direction. This problem tends to be much more prevalent when electrical wires are used to connect the truck pickups to the motor leads, and poor solder joints or broken wires end up being the usual culprit.
 
Mixed Freight said:
I would also recommend a figure "8" layout for break-in purposes, not only to help exercise the trucks in both directions, but also to diagnose possible electrical connection problems in the loco. For instance, I have seen more than one loco do just fine running laps in a clockwise direction around an oval, but stall out or quit running all together going in a counter-clockwise direction. This problem tends to be much more prevalent when electrical wires are used to connect the truck pickups to the motor leads, and poor solder joints or broken wires end up being the usual culprit.
Click to expand...
Thanks, I agree, while a figure 8 would help in that area, But I am ok picking up and flipping the loco in the other direction after a bit too. But I am glad you mentioned it, Gives me something to work out a bit more. Because I have had in the past locos that had that Problem but that was years ago. So gives me something to think about at least.
 
Bushel86 said:
The Problem Is I don't trust the Mfg Stats, I rather have real world knowledge of what people actually have found out for themselves. That's why I don't just go by the MFG. And if I have to do anything to the loco to make it run on that tight of a radius its not really worth it. since my main layout won't have that tight of a radius to begin with. So I just want to be safe with making sure the curve is broad enough for everything But minimum enough to be stored without to much space being used... So Thats why I was thinking 12" radius for the layout. I can make the layout 26" deep and it can still be stored in my hobby rooms closet without issues.

While My main layout will have minimum of 18" radius. Its no problem for anything on the main layout. But this layout will also scratch the itch of continous running without me needing to incorparate it into my main layout.
Click to expand...
You might want to try the Kato Unitrack. That is what I use for the very same
Bushel86 said:
So While I am Building my Large N scale switching layout. after starting a new from Ho scale. I decided I want to Build a Test Layout, This layout is to serve 3 Major factors..

1.) It will be my Dcc Programming Track.
2.) Must be used to Break in locomotives,
3.) Layout will be used to test new scenery ideas and techniques before applying to main layout.

While This Layout also has to Be Small, and be able to be stored when Not in use. It will not be part of a bigger layout or be used for anything other than breaking locomotives in and programming them.. What I need to know. Since I do not own or plan to own in the for seeable future Modern Large diesels, is What is the minimum radius I can use for every Large Diesel loco? I do not plan on doing any steam.

I had Plan on using 12" radius as my minimum. If I can sqeeze it down to 11 That be better.

I do not care about how silly the loco looks, Thats not what this Layout is about.
I also Agree Bigger radius is Better, But Again, this is not a show layout or to be used for such.. And so I am not trying to make it as such.

I really Just need those of you who have large modern Diesels to Just help me know what I can get away with without binding the trucks. because I do not own any myself But want to plan ahead for such if I ever get the itch too.

While my main layout is Focused on Lance mindheim point to point Operations, This test layout I want to be able to accomadate for modern diesels if my desire changes for my main layout. therefore I already have something I can use to Break in and Program new locomotives without having to use the main layout.. and If I can fit this layout into a closet when Not in use that will be even better.

Once you can help guide me to a certian radius, I can then choose the size of the layout, and for me the smaller the better, simply for storage reasons.

Also I should mention I do not plan on pulling any cars with these large Locos, If I do make the layout more display like I use small power for it. But to break in a Big Loco its just be light power to break in the motor. So having said that. If I can keep the benchwork at 24x48" for this layout I would prefer that.. other wise if I stay with 12" radius I will have to Go a bit wider and the wider it becomes the harder storage becomes..

Thanks for any and all help.
Click to expand...
I got just the thing for you. Use Kato Unitrack which is what I use for the very same things that you list. At Least the first two. It is readily available, easy to set up and take down and comes in a variety of curve radii. As far as scenery use a piece of expanded Styrofoam to practice on. There are lots of You Tube videos on how to do scenery and there is no one best way. Pick the one you are comfortable with.
 
Most modern N scale locomotives these days will run on 9.75" radius curves just fine. The Big boy might need 11R.

They may not look great, especially if viewed from above, but from lower angles (closer to eye-level) they look much better.

-- Andy
 
When it comes to reliability, Kato Unitrack is practically bullet-proof, with excellent rail joiners, supported by the attached roadbed (another advantage in ease of use.) You may not like the roadbed color, tie spacing, or the rail height (code 80), but it is excellent track operationally, and few others match it's variety of track pieces (curve radius/span, straight lengths, switches, crossovers, single/double track, etc.) Doubletrack curves are superelevated (banked slightly).

== Andy
 


BigJakeJ1s said:
Most modern N scale locomotives these days will run on 9.75" radius curves just fine. The Big boy might need 11R.

They may not look great, especially if viewed from above, but from lower angles (closer to eye-level) they look much better.

-- Andy
Click to expand...
Folks with modern day N-scale locomotives that do not run well on 9.75" radius curves will no doubt disagree with you.

BigJakeJ1s said:
When it comes to reliability, Kato Unitrack is practically bullet-proof, with excellent rail joiners, supported by the attached roadbed (another advantage in ease of use.) You may not like the roadbed color, tie spacing, or the rail height (code 80), but it is excellent track operationally, and few others match it's variety of track pieces (curve radius/span, straight lengths, switches, crossovers, single/double track, etc.) Doubletrack curves are superelevated (banked slightly).

== Andy
Click to expand...
More advanced hobbyists use flex track (or even hand-lay) for totally unlimited track configurations and unparalleled looks when using track ballast in varieties of colors that duplicate the prototype's ballast.
 
Mixed Freight said:
Folks with modern day N-scale locomotives that do not run well on 9.75" radius curves will no doubt disagree with you.


More advanced hobbyists use flex track (or even hand-lay) for totally unlimited track configurations and unparalleled looks when using track ballast in varieties of colors that duplicate the prototype's ballast.
Click to expand...

I have run plenty of modern 6-axle diesel locomotives on 9.75R Unitrack curves with no problems. They don't look too good doing it, but they make it all the way around, over and over.

The OP wants a small layout to use (presumably quickly) while he completes his real layout. Perfect application for Unitrack: You don't even have to fasten it down!

If he wants, he can use a pack of four 9.75R45 curves for the apexes, and another pack of 11R45, 12.375R45, or 13.75R45 curves for "easements."

But then again, I suppose he could waste more time on separate roadbed, trimming flex rails to different lengths, fastening the flex down so it holds its shape, soldering rail power connections, etc. if he wants.

But none of that is needed with Unitrack, so he can quickly enjoy running some trains while he works on the real goal, his main layout.

-- Andy
 
BigJakeJ1s said:
I have run plenty of modern 6-axle diesel locomotives on 9.75R Unitrack curves with no problems. They don't look too good doing it, but they make it all the way around, over and over.

The OP wants a small layout to use (presumably quickly) while he completes his real layout. Perfect application for Unitrack: You don't even have to fasten it down!

If he wants, he can use a pack of four 9.75R45 curves for the apexes, and another pack of 11R45, 12.375R45, or 13.75R45 curves for "easements."

But then again, I suppose he could waste more time on separate roadbed, trimming flex rails to different lengths, fastening the flex down so it holds its shape, soldering rail power connections, etc. if he wants.

But none of that is needed with Unitrack, so he can quickly enjoy running some trains while he works on the real goal, his main layout.

-- Andy
Click to expand...
The O.P. will be elated to know this, after almost a year since his posting. Even though your suggestion(s) don't necessarily meet all of his criteria.
 
I thought the guy said the layout was sort of a test bed for him to learn on - that is, learn how to build a nice flex track based layout.
Seems like the Kato track would be a waste of time and money in such a situation.

Just because a loco can negotiate a 9 inch curve does not mean
you should do it. Sharp turns are hard on mechanisms...

I have a test layout with "9 & 12 curves.
My Kato FEF does not run on either. It had problems even at 14.
I do not believe the Big Boy will work either, though I do not have a Kato version.
Atlas Trainmaster binds up and slows on even the "12.
 
Note there is an 8.3% difference between 9" and 9-3/4" (Kato) radius. Sometimes that's enough to make a difference.

Also, transitioning directly from tangent sharp curves is even harder.

Easements (real, or approximated with intermediate-radius sections) can make the difference between working or not on the tighter curves.

Then there's wear on wheels (and track) due to wheel slippage in sharp curves, too.

-- Andy
 
BigJakeJ1s said:
They sound like good candidates for Kato's UniTram tracks (double tracked, no less.)

-- Andy
Click to expand...
Not really, I don't think Kato makes a small enough radius. Smallest radius I could find for Unitram was 180mm. Unitram makes a 140mm (5.5in.) and a 103mm (4.5in) radii. Protyotype streetcars could typically handle curves of 35 feet radius which is about 2.6 in. in N scale. I went with the 5.5" radii as that was what the Bachmann Peter Witt could handle.
 


inkaneer said:
Not really, I don't think Kato makes a small enough radius. Smallest radius I could find for Unitram was 180mm. Unitram makes a 140mm (5.5in.) and a 103mm (4.5in) radii. Protyotype streetcars could typically handle curves of 35 feet radius which is about 2.6 in. in N scale. I went with the 5.5" radii as that was what the Bachmann Peter Witt could handle.
Click to expand...
Mea culpa. My reply should have said, "Tomix makes a 140mm (5.5in.) and a 103mm (4.5in) radii."
 
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