It's certainly possible, but not very practical.
There are two primary lug making techniques used today. One is the traditional stamped lug that is stamped from sheet metal, folded, and then welded. The other, developed in the late seventies/early eighties, is the "investment cast" lug that represents the overwhelming majority of lugs on today's lugged bikes.
Retired framebuilder Dave Moulton has a brief description of both lug making methods
HERE.