Recommended minimum radius

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eddie

New Member
As I am trying to think the HO modeling thru before I try it again I have some other questions -

I'd like thoughts on what is a reasonable minimum radius to use. What I am thinking is someting that accommodates most HO trains.

I suspect 18 inches is to tight but I am not sure. I want to run very nice quality locomotives.

Are there some general guidelines on what will run on 18 inch vs a larger radius?


By the way the replies on my question about derailments were excellent!
 

Trucula

Drum Driver
4 wheeled truck engines love 18" radius. However some "quality" 6 wheelers will work also....But I think, IMO, 22in. looks better then an engine looking like a sprint car going thru a tight turn with the truck turned far outta whack....Steamers are different....some 4-8-4 will work an 18" because some don't have flanges on center wheels. If its an issue with space an you have to use 18", stick with engines that are shorter and look more appropriate on the turns. But if you have room to spare, don't go less than 22 and everything will work.
 

davidmbedard

DCC Sound Guru
As I am trying to think the HO modeling thru before I try it again I have some other questions -

I'd like thoughts on what is a reasonable minimum radius to use. What I am thinking is someting that accommodates most HO trains.

I suspect 18 inches is to tight but I am not sure. I want to run very nice quality locomotives.

Are there some general guidelines on what will run on 18 inch vs a larger radius?


By the way the replies on my question about derailments were excellent!
You need to give more info...

What prototype do you intend to model? What kinds of locomotives and rolling stock? Will your curves have easments?

If you want my opinion, I tend to go by the 28" minimum radius rule. It will allow you to run pretty much anything. If you go less than 28", then you will have to make certain compromises....

David
 

jeffrey-wimberly

Dr Frankendiesel
If you are really pressed for space like I am and HO is what you want to run, you can get away with 18" radius as a minimum. I run locos ranging from a diesel Hustler to an AC4400 without any problems. I would suggest though that you use 22" radius as a minimum. It'll give you a bit more flexibility.
 

Larry

Long Winded Old Fart
I run 28" or larger, but I also have plenty of space & I run large diesels. It also helps to have wide curves if your going to pull long flat, box, passenger & other long cars. If your just going to run the early years of engines in both steam & diesel, then 18 to 20" will probably work. If you have a 4x8 board then go as wide as you have room for.
 

Gary S.

New Member
Eddie, don't neglect to take into consideration your turn-out sizes too. Smaller engines such as shorter 4 axle deisels work okay on #4s, but a big new modern 6 axle diesel may not look so good, or work so well.
 
I run all steam and 18" is fine for 0-4-0, 0-6-0, 0-8-0 for sure
I find that the 2-8-4 runs ok as well. My 2-10-4 is fine because it has no center flanges. The 2-8-8-2 and the 4-8-8-4 will do it at creeping speed but as noted is very ugly and between track clearances have to be so great it isnt nice.

I have sections of 18" that only switchers would go in for industries and such.

I prefer 24 to 36 for the big guys and longer trains to get the speeds that look good.

Good luck
 

IronBeltKen

Lazy Daydreamer
My minimum mainline radius is 30", this is because I run modern-era Walthers 89ft auto racks and [IMHO] they look weird on anything tighter. On the other hand, some of my steel mill spurs are 15" because only short-wheelbase cars and switchers need to go on them.
 

OldGettysk

Running the MC & Buffalo
Eddie welcome to the forum . I use 22' radius and have no problem with my larger passenger cars and rolling stock !!
 




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