Track spacing for a double main for Ho scale.

[FR8TRNZ1]

Just wondering how far apart do you space a double main, and you do keep this the same for curves. And is this measured from the center of the track.

 

[Dougget]

I think the magic number is 2 inches. A little more around the curves 2.5" maybe 3". Really depends on the turn radius and car length. The tighter the turn and the longer the car the more overhang you will have, so you need more space.

Do a google search for "HO Scale Track Spacing" and you'll find many recommendations. When it comes down to it, you need to find out what will work for you. Pin down some pieces of track, get your longest cars, and see how they fit. Adjust a little, add an eighth or quarter inch just in case, and go for it.

Doug

 

[waltr]

The NMRA has guidelines in their Standards:
http://www.nmra.org/standards/sandrp/s-8.html

The answers depends on track radius and car length.

 

[fire28]

My Mains are 2in apart....I haven't gotten to any curves yet...

 

[TRAINFAN9510]

Radius is a big factor. you could have your tracks 2 inches apart with 60" radius curves and it is fine. But if you are running 18 and 20" radius curves, your cars on the 20 will overhang and interfere with trains on the other track. Our old layout had 2.5" spacing for straights, and 3" on the curves (we had 19" and 22" curves and it worked out fine)

 

[Selector]

For curves in HO less than 30", you would need near 3" of separation between the two track centers. Below 24", you would want just over 3.25" if you are running longer autoracks and passenger cars. This is particularly critical for steam locomotives with wide cylinder saddles and for the overhang of the cab roof...the two rear corners will catch on things, and this is just as true with an articulated steamer...ask me how I learned this.

As suggested above by dougget, there is no substitute or better insurance against track separation, minimum curve, and grade problems than to mock it up first and do trials with the very trains you intend to run over them.

 

[FR8TRNZ1]

Thanks for all your replies.
I am going to use 30" radius curve on the double main line.
On the branch lines and tracks in town I was thinking of using a 22"-24" radius. The area where I am using the smaller radius 22"-24" I am running smaller switchers and Geeps, maybe a SD40-2 once in awhile, also modern box cars and grain cars. I think I should be ok using this radius in town and on branch lines.
Any Pictures of your layouts with some double main lines going into a curve.......Thanks.......

 

[TRAINFAN9510]

This is our old layout. It has 19" inside and 22" outside radius curves

 

[Selector]

This is a 36" curve with only 2.5" between centerlines.

 

[GrampysTrains]

30" curve with 3" c-c spacing. DJ.

 

[Rico]

This is 1 1/2" spacing on the mains and yard, I think that's what you get with two #6 switches in a crossover. On 28" and 30" curves I think I have 2 - 2 1/2" spacing.

 

[TRAINFAN9510]

Way to go guys, make my picture look like absolute crap! lol, but really, wow, impressive work!!