I think you're really talking about "limits" rather than "drawing size",
which has no meaning in acad-speak. Look up "limits" in the help.
Limits are controlled by the LIMITS command, and if you are getting the same
limits on all your drawings it is probably coming from your default drawing
template. Change it in the template to what you want and every *new*
will be the same. In drawings *already created*
, use the LIMITS command to
change them to what you want, or, if there are too many to change manually,
create a script to do it for you.
I'm no expert on scripts, but someone else might be able to advise on that.
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