Turn Radius

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NickB

Wannabe Engineer
Alright because that's one thing that I'm worried about with latest layout shape is that I have some turn radius of about 13.5", and I'm afraid my 4-8-4 won't make it around it. I'll give it a whirl tonight after work.
 

SpaceMouse

Fun Lover
Alright because that's one thing that I'm worried about with latest layout shape is that I have some turn radius of about 13.5", and I'm afraid my 4-8-4 won't make it around it. I'll give it a whirl tonight after work.
I had a 4-8-4 that I ran around 18" turns--but it didn't like it. Think 22". I run small steam--the size that would fit in the 4-8-4's tender. I stick to a minimum of 18".

Think #6 and above turouts as well.
 

Trucula

Drum Driver
Usually a 4 wheeled truck on a diesel engine likes 18" radius, That's how they come in a kit...A 6 wheeled truck likes a 22" radius....Now that's diesels...Steam is different.. Some 4-8-4 will work on 18" but that's usually because some of the drive wheels don't have a flange on them. I personally wouldn't put anything over a 2-6-0 on an 18" radius. Just for smooth operation.
 

NickB

Wannabe Engineer
Well bummer looks like I'm going to have to do a little more re-designing on the layout then to have a turn radius that will suit my 4-8-4 and some of my early diesels. Thanks for the info guys.
 

NZRMac

In Training Down Under.
I'm with the other guys Nick, think 22" minimum otherwise it becomes unreliable and looks awful.
 

jeffrey-wimberly

Dr Frankendiesel
All the curves on my layout are 18" radius. I run all diesel power, 4 axle units as well as 6 axle and none of them have any issues with the turn radius with the exception of appearance, which is easily overlooked.
 

kjd

Go make something!
I have a HO 4-8-4 that doesn't even like 24" radius, almost 2x bigger than the curve mentioned above. If NickB is in N scale he should be ok. It is always best to go with the biggest curve possible even if it means leaving out some track. Most model railroaders try to do too much in a given space. I am building some modules and keep reminding myself that in HO a 2ft x 4ft module is only slightly larger than an American football field.
Here is a link to a photo of my next up for construction module. It is BN jct in Hillsboro, OR. The yellow lines are outlines of the 3 modules it will take to build it in a way it will fit in my Civic. The ends are 24" wide and the curve is 42" radius. In HO, the real life the curve is about a 48" radius and it looks pretty sharp standing on the ground next to it.
http://members.trainorders.com/pmack/temp/BNjct2.jpg
Thanks for letting me go off about one thing that bugs me, overly sharp curves,

Paul Mack
Hillsboro, OR
http://members.trainorders.com/pmack/train.htm
 

HaggisKennedy

Coal Shoveler
13.5"??? Is that N-scale? I've not seen anybody do a 13.5" radius curve; Atlas makes a 15" sectional curve (I have one for a tight spot), but 13.5"??? I'd think flextrack would kink at that radius....

Kennedy
 

NYC_George

Well-Known Member
Curve Radius

I have a HO 4-8-4 that doesn't even like 24" radius, almost 2x bigger than the curve mentioned above. If NickB is in N scale he should be ok. It is always best to go with the biggest curve possible even if it means leaving out some track. Most model railroaders try to do too much in a given space. I am building some modules and keep reminding myself that in HO a 2ft x 4ft module is only slightly larger than an American football field.
Here is a link to a photo of my next up for construction module. It is BN jct in Hillsboro, OR. The yellow lines are outlines of the 3 modules it will take to build it in a way it will fit in my Civic. The ends are 24" wide and the curve is 42" radius. In HO, the real life the curve is about a 48" radius and it looks pretty sharp standing on the ground next to it.
http://members.trainorders.com/pmack/temp/BNjct2.jpg
Thanks for letting me go off about one thing that bugs me, overly sharp curves,

Paul Mack
Hillsboro, OR
http://members.trainorders.com/pmack/train.htm
This 24" curve radius is one you made or some 24" radius curved track. If you make your own as I do any slight imperfection in any radius will cause you trouble. I use the cruve radius metal templates and even then some times I have trouble and have to relay the track.

NYC_George
 

Trucula

Drum Driver
Flex can be a problem on curves...the tighter the curve, the more problems!...You have to remove some ties to add rail joints...This can cause kinking of the rail after awhile at the joint if ties are not replaced and spikes used to support the rail. Soldering the rail before you place it helps (use rosin less soldier) and stagger the joints (which will happen automatically "some" when curve is formed) but after a while if you find minor derailments of a pilot truck on a engine or on a certain rolling stock, check the joints with a gauge.
 

kjd

Go make something!
This 24" curve radius is one you made or some 24" radius curved track. If you make your own as I do any slight imperfection in any radius will cause you trouble. I use the cruve radius metal templates and even then some times I have trouble and have to relay the track.

NYC_George
It is actually a brass NP A-5, a largish Northern. It won't go around Atlas 24"rad. sectional track set up on a flat surface. The pilot truck hits the cylinder cocks (?) on the bottom of the cylinders. It is ok so far though because the only curve I have is a #9 turnout and it looks great there! When I get DCC and lights in it (and more track/modules) I will figure something out.

Paul Mack
Hillsboro, OR
http://members.trainorders.com/pmack/train.htm
 




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