double track mainline

Hello fellow railroaders,

My name is Mike McCaffery and I live in Northeast Pennsylvania. I currently have a single track mainline with 8 foot curves on the corners. I would like to add a second line to my railroad. I could enlarge my 8 foot curves to 10’s and put the 8’s on the inside. Would that leave enough clearance on the curves? How far apart would my straights have to be to allow this on the corners? I’m not new to this hobby but I never played with double mainlines before and could use some suggestions. I was informed by my wife that if I ever touched this layout again, she would kill me, but I would really love to do this.

below is what 9.5, 10 and 11.5 curves look like.

the 8 ft and 10 will give you 12 inch’s between centers

Dave

My layout has “Triple” mainlines and I used 10ft diameter curves on all 3 mainlines and still have clearance on curves. It’s all in the planning of the straight away. I wanted all 3 of my mainlines to have 10ft diameter curves so I could run my big diesels anywhere that I wanted to. I also have all X-Large Aristo switches which are also 10ft diameter. When I run all 3 mainlines my family is pretty much entertained.

Here is a photo link of the spacing I used which worked out well for the big stuff >

http://www.flickr.com/photos/usatrainsgscalegroup/8350982450/in/set-72157632445753782

Of course all 3 mainlines do not run together like this through out the entire layout, they eventually split up.

On another note each mainline does have a isolated cross over and it’s own transformer. Crossing trains is another cautious adventure but it can be done by properly setting each tranformer for each track.

To “nest” 3 curves with the same radius trak, you have to do what EMD Trainman did, insert straights in the outer curves. It does give an irregular appearance to the curves.

You can also use different radii, like 10, 14, 16 foot, which will give you 12" center to center between the adjacent curves.

Lots of options.

Greg

Gerg, What would be the center-2-center spacing of the straight-aways into/out of those curves?

Theoretically, the same as the differences in diameters…

I see I did say radii above when it should have been diameters…

so if there was a 1 foot difference in radius between curves, that would have 1 foot center to center.

so 8 and 10 foot diameter curves would have 1 foot centerline to centerline …

Greg

Simplest approach is to use a rail bender and flex track. Just remove the screws from the tie strip on Aristo or USA track and bend away. You can use the existing 8 ft diameter as a pattern and then just space the next parallel track about 4" away. Way simpler than trying to buy sectional curves. And as a bonus, you can bend in the easements for super smoother running.