I can come up with a lot of ideas to fill a 31x51 foot basement with trains. Mine won't necassarily do you any good however unless I have a better understanding of what you want and what your experience level is. I'd suggest giving this thread a read, and then, come back to your thread and tell us what you want.
http://cs.trains.com/forums/1451931/ShowPost.aspx
if you want a guide on how to plan a working railroad (in miniature ), here's how I've been going at it for my next one..
http://www.rolleiman.com/trains/clinic4planning1.html
edit: Sorry, should have followed my own advice and read your post a little more carefully..
(leaving my other answer in tact)
An few good ideas here.
http://cs.trains.com/forums/1444020/ShowPost.aspx
Hi Jim. What an opportunity to create from scratch!! I suspect you aren't a newbie as you mention "trains", and new track. Don't ignore the possibility of a swinging gate with the track on top of it, but the benchwork better be good and solid before trying that.
Some things to consider: Length of the opening vs height of the track; will it clear the floor when lowered? Avoid having track ends anywhere near the aisle; it only takes one shirtsleeve to pull them out of alignment if they aren't indented enough. Electrical and mechanical guarding to prevent the Midnight Express from going into the drink, even if backing up? Counterweights?
In my schedule to construct is a Walthers Bascule bridge across a 30" opening to my "pit". It looks like it'll sit on a diarama-type frame about 3" thick (plus bridge) with the bridge and frame all pivoting down and out of the way behind a guard so passersby won't be bumping into the top of it all when lowered. I won't likely get to it before scenic-ing the rest of the Plywood-&-Western RR. even though the design has been sitting in my book for a couple of yrs :+)
There's a wealth of ideas in the various publications from our hosts at MR, so don't dive in too quickly. A lot of sheets of doodle-paper and a couple of new pencils and many erasers are your best friends.
Do you have a trackplan to show everyone? We could get a lot more specific with some more details about what you're thinking about. Meanwhile, I'll admit to being a little envious of all that space. That's big enough for a club layout.
Have fun, George