It's not a bad idea to set limits for your AutoCAD 2012 drawing. Limits in AutoCAD represent the rectangular working area that you'll draw in, which usually corresponds to the paper size. Setting limits correctly lets you display the drawing grid over your working area, use ZOOM All to display that working area, and plot your working area from model space. The following table sets out the dimensions in whole feet or feet and inches of work areas for different paper sizes at different drawing scales.

Drawing Scale 8-1/2" x 11" 11" x 17" 24" x 36" 30" x 42" 36" x 48"
1/16" = 1'–0" 136' x 176' 176' x 272' 384' x 576' 480' x 672' 576' x 768'
1/8" = 1'–0" 68' x 88' 88' x 136' 192' x 288' 240' x 336' 288' x 384'
1/4" = 1'–0" 34' x 44' 44' x 68' 96' x 144' 120' x 168' 144' x 192'
1/2" = 1'–0" 17' x 22' 22' x 34' 48' x 72' 60' x 84' 72' x 96'
3/4" = 1'–0" 11'–4" x 14'–8" 14'–8" x 22'–8" 32' x 48' 40' x 56' 48' x 64'
1" = 1'–0" 8'–6" x 11' 11' x 17' 24' x 36' 30' x 42' 36' x 48'
1-1/2" = 1'–0" 5'–8" x 7'–4" 7'–4" x 11'–4" 16' x 24' 20' x 28' 24' x 32'
3" = 1'–0" 2'–10" x 3'–8" 3'–8" x 5'–8" 8' x 12' 10' x 14' 12' x 16'