As I've noted elsewhere in the site, most of the time there is a better alternative than an HO scale 4X8 layout for any space. They are physically hard to move up or down stairs, around corners, etc. Because the minimum radius must be
22" or less, it somewhat limits the usefulness of the completed 4X8 as an element in a later layout. And a big ol' 4X8 chunk
of layout (plus its aisles) may be hard to work into a new space when you move.
By contrast, some smaller layout sections
(as in Model Railroader's Milwaukee RR "Beer Line" project beginning Dec. 2008 in the magazine) would be
much easier to move and to incorporate in a later design in a different space. So if you are in a situation where you might
move someday, for example, it might be better to build sections instead.
And if you aren't planning to
move, building a layout at least partially along the walls often provides a much better solution with a longer mainline run,
more spacious aisles, and broader curves than an HO 4X8 track plan.
Or if an island style plan is
what you desire most, 5Xanything is usually a better choice than the HO 4X8. Layout footprints of
5X8, 5X9, 5X10, etc. all provide a more comfortable space for an engaging HO track plan than the sacred sheet, but with only
a minimal increase in overall square footage.
But
what if you have already built the 4X8 train table? Or you just can't bring yourself to cut a sheet of plywood (or
have it cut). How to make best use of it?