I would recommend you consider keeping the width of the two 30" wide sections to 24" from the wall to ease reach in..
Chris
My N Scale laout is about the same size and shape. I used domino sections made of 1X4, cross-braced and covered with 1/8" plywood. The dominos are screwed to the wall studs and supported underneath with diagonal braces. The domios are screwed together at the ends as well as being attached to the wall.
The only thing I would change is the one long bench 102 x 24. I would make it two benches 51 x 24 instead. This would give you the same bench but make it easier to transport.
Johnnny_reb Once a word is spoken it can not be unspoken!
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Good choice of basement for the trains. regarding the layout height, i'd go with the 40" or even 42". To reach the corners if needed, buy or build a stepstool. this will allow you to reach the corners, and Nik can use it to stand on till he grows up--. Also, the higher benchwork will be more comfortable to get under for those times when working under the table is necessary. I set my layout at 48" so I could use it for storage and ease of use when it was time to be under the table.
Looking forward to seeing your track plan
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