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Jack Stein

wrote:
OK, I got use of a computer with XP and have been learning SU7.
Pretty cool. As a kid, I worked just long enough as a carpenter to be
dangerous, but not to read blueprints. Now I'm trying to create some.
As a mechanical CAD designer, I'm used to working in thousandths of an
inch. I'm sure that level of accuracy is not needed for architectural
drawings. Or is it?

Woodworking machines may be built to 1/1000 of an inch, wood work is
measured in 1/16 or 1/32 of an inch. I measure everything in 1/16th
because I can't see 1/32, so I use 1/16th + or -, which probably gets me
around 1/32. when drawing stuff up to build, 1/16th is all I need.

Main question. When I'm creating detailed drawings of the deck I'm
repairing, do I create them using nominal dimensions (2"x4") or actual
dimensions (1-1/2"x3-1/2") for lumber? Seems like it should be the
later, specially for cutting to length. What kinda tolerances are
typical for framing and the like?

Wouldn't make any sense to draw something up using wood dimensions that
existed before the lumber was dried and planed to final size? If you
are using 6" lumber for the floor, and need 50 pieces, you will be off
by 25" if you pretend the lumber is 6" wide, and not 5 1/2". Ordering
the lumber you of course use the rough cut dimensions.

--
Jack
Go Penns!
http://jbstein.com