Welcome Nevin, Your wife sounds like a smart woman . I'll take a stab at a few of your questions.
1) Yes, 8 foot diameter will be quite adequate for just about all rolling stock in Fn3 (1:20.3)
2) a 7 inch center to center is what I use
4) I have heard very good things about AMS code 250 flex track. The St.Aubins ad in the new GR had it highlighted
6) Craftsman kits are available from Smith Pond Junction - http://spjrr.com/masterkits.html and Garden Textures - http://web.mac.com/gardentexture/iWeb/Site/Home.html . Many of the kits are 1:24 but at least with the SPJ kits they are just plans with scale lumber so dimensions of the door or the entire building could be adjusted.
7) There are many ways of laying track to directly on the ground or gravel and ballasted to elaborate raised track of PVC ladder systems or wooden trestles and bridges. I would keep an eye out for all the pictures from last week's National GR convention in Vegas for examples. Also consider contacting the local clubs out your way.
Have fun, Brian
A questions for you Nevin.
What kind of power are you planing on using? (This will somewhat dictate the types of track available)
Now on with some of the other questions.
1. If you are staying with 1:20.3 the 8 foot diameter should be fine for most narrow gauge equipment. I would however see if you can manage to maintain a 10 foot diameter minimum just in case something comes along that requires them or your interests change a little.
2.The minimum track center difference will change depending on wether you are on a straight section of a curve. Urban Eagle's page has useful railroad dimensions in many scales.
3. I don't see why not
4. There are many brands available out there it really depends on what you are looking for. A few companies do offer turn-out kits in the code 250 and 215 rail sizes.
5. There are larger comercial turn-outs available again size of the turn out will vary by manufacturer. For example an Aristocraft #6 turnout is about 3 feet long.
6. and 7. Brian answered them pretty well. Getting any advice from someone in your area that has done trackwork will be helpful.
Most of all have fun, this is supposed to be a hobby
Jack
Nevin; Welcome to Large Scale. The other guys pretty well answered all your questions. The only thing I would add is to emphasize "flex track". Now this stuff is not quite like the flex available in the smaller scales. In most cases you will need to acquire a rail bender, some of the "lighter weight rail" can be bent by hand but a rail bender will give better control of uniformity to your curves. "Flex" comes in 5, 8, and 10 foot lengths, depending upon manufacturer and weather you go with brass, stainless or even aluminum. You will want to use rail clamps, either Hillmans or Split Jaw, both are excellent and will insure better conductivity and positive alignment of the joint. If you are going to use rail power, as I do, using rail clamps, I have feeder wire such that an engine is not more than 50 feet from a power feed. If you elect to go with battery power than your only concern with the joints will be positive alignment.
If you scan back across some of the older postings you can find several methods of laying track. The method that works well for me is: Dig a trench about 2 inches deep, put down a layer of gardeners fabric, to stop unwanted weeds yet allow for drainage. Next fill the trench with quarter inch minus crushed rock and mound up so the road bed is about an inch above ground level. The fabric under the gravel prevents the gravel from migrating down into the soil, thus keeping a good foundation. Over the gravel another layer of fabric (to prevent weeds) lay the track and then use crusher fines (or chicken grit) as ballast. You will need to experiment with some of the different ways listed in the older posts to find the one that will work best for you.
In the garden there really is no "best" way of doing anything. What is best for me could be the worst possible choice for you, as climate and ground conditions change from area to area so do the needs change.
Now get outside and play in the dirt. My most common advise to someone new to GR I say get a starter kit, engine, 2 cars, a 4 ft dia. of track, and a transformer. It is economical and gives something to start playing with right away. Then when you start laying track for real you can toss the 4 ft circle of track, get a few larger cars. The little engine in the kit will always be needed for "yard work" and "local freight."
Tom Trigg
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