# what size u turn radius for 5 car ho train



## gandy dancer#1 (Jan 21, 2012)

Maybe i am not stating it right, so forgive me:: What is the smallest horse shoe turn i can make ?? Yeah i know youre going to tell me look at track plans, but just confuses me, and i have yet to see any ones plans that fit my application and what i think looks right i have seen figures of 18 inch radius please some one explain how that is measured and thanks for yor time:thumbsup:


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## gunrunnerjohn (Nov 10, 2010)

What type of stuff are you going to be running on it? The minimum radius will be the same as whatever the minimum is for the largest piece of equipment requires that will use the turn-around.


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## sawgunner (Mar 3, 2012)

your radius is measure from center of track from a center point. 18" radius curves are 36" diameter curves.

with flex track i believe that you can get as tight as 14" radius in HO scale.

i'll go take a couple pics for ya with what i use for marking my curves on my layout. that may help explain it better than i can at the moment

ok so what i did was set my tremble beam compass to 24" marked a center point of what would be a full circle and then marked the 24" turn i wanted to make. then i took a piece of flex and lined the nail holes up with my mark and nailed it down all the way around and it formed my 24" radius curve
PICS


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## gandy dancer#1 (Jan 21, 2012)

*what size u turn radius*

Whoa i need some of them tools to go with my drafting tools:laugh: i think i am getting your point. I am working with a table top 6' x 6' till we go bigger i am runnig all ho most 5 cars including loco. like 1 box car, cabbose, tanker open gondola and loco!! currently just a circle on outside perimeter of board. I would like to fix the boy a turn out and come back somewhere inside othe loop a piece and then make another curve and rejoin track in same direction. purpose is so he can pull along side the stock pens i got from da blaze for his christmas, and continue on!!kinda if yo will an oval with a funky s in the middle:laugh: I am one of those guys i reckon like i have been doing, just put track together and see if it works I do thank you for response, and did help in my thinking!! and will keep coming back to look as i go along very valuable as you have given me a visual, as with one eye i am very visual:laugh:


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## sawgunner (Mar 3, 2012)

a little something i whipped up the outside is 24" radius the insides are 15" radius you can do the crossing or do one track above the other. one track runs ya one direction the other one turns ya back the way you originally started. they are atlas snap switches as well. the grid is 6'x6'


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## cv_acr (Oct 28, 2011)

Keep in mind you have _two_ reversing sections that need to be dealt with in that plan...

Also, 15" radius is pretty extremely sharp for HO.


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## sawgunner (Mar 3, 2012)

I did in DC mode given it'll be for a kid i'll work on some others in the mean time.

15" is extremely sharp if your using anything but 40' cars and from the sounds of it he will be fine in that department


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## tooter (Feb 26, 2010)

sawgunner said:


> I did in DC mode given it'll be for a kid i'll work on some others in the mean time.
> 
> 15" is extremely sharp if your using anything but 40' cars and from the sounds of it he will be fine in that department


With 10' cars you can use 6 inch radius curves...


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## sawgunner (Mar 3, 2012)

here are a couple more ideas

out sides 24" in sides 22" #4 custom line Mark IV turnouts


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## tkruger (Jan 18, 2009)

If you use 15r you will be limited to comfortably running GP 35 or smaller locos and 40 - 50 foot rolling stock. By going 18r you are open to most older items including steam engines. Several of the items sold today will require a 22r minimum.


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## T-Man (May 16, 2008)

In throwing my idea out here. It all depends on the length of the individual cars. At some point the train will be too long to handle a u turn. Trial and error is what makes the hobby learning curve.


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## gandy dancer#1 (Jan 21, 2012)

*What size U turn radius*

Hey SAWGUNNER:: Many thanks on the layout drawings you posted all excellent and dam close to what i was thinking, :thumbsup: just wasn't sure in what direction to head!!! I will stay away from any reverse loops as don't want to invest at this time in reverse module. current 6 x 6 set up is temporary till spring, as grandpa has been draggin butt getting something other than plain flat table going for grndson and he has been asking when we going to make something better:laugh: Sometimes a fella just needs a boot to get thinking going:thumbsup: I am runnig standard ho cars, sorry not far enough into the hobby to quite comprehend when you guys talk 40'or 50' cars, I grasp that is the real cars size, but haven't measured the cars to see what they represent in real life yet. guess i had better do that so can keep up with you pro's:laugh:


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## cv_acr (Oct 28, 2011)

A 40' (scale) car is roughly 6 actual inches long in HO scale.


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## cv_acr (Oct 28, 2011)

sawgunner said:


> I did in DC mode given it'll be for a kid i'll work on some others in the mean time


I not sure what you mean when you say you did the drawing in "DC mode".

A reversing loop is a reversing loop, and has to be handled the same way whether the layout is DC or DCC.

The track diagram is pretty independent of the control system, although a complicated track plan in DC can create complicated blocking and wiring if you want to run multiple trains.


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## gandy dancer#1 (Jan 21, 2012)

*what size u turn radius*

Hey cv acr:: So if car is 6 inches long it is in real life, 40 footer?? I have a passenger car that is ten inches long, so in real life and 80 footer???


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## sawgunner (Mar 3, 2012)

gandy dancer#1 said:


> Hey cv acr:: So if car is 6 inches long it is in real life, 40 footer?? I have a passenger car that is ten inches long, so in real life and 80 footer???


10" 1/87 = 72.5' prototype


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## cv_acr (Oct 28, 2011)

HO scale is of course 1:87, so one real foot equals 87 feet in HO scale. (Well, 1:87.1 technically) Most passenger cars are 85' long, so a ten inch car, scaling out to between 70 and 75 feet is a little undersize.

A lot of older passenger car models were made to a shortened length to handle the sharper 18" curves that are standard for sectional track in trainset packages.

You can get scale rulers marked in HO scale feet at the hobby shop, or you can easily convert real measurements to approximate scale ones by simply multiplying by the 1/87 ratio.


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