Finding a stud behind plaster and lath is hit-or-miss with a typical stud finder. Here’s a better method. Tape a rare earth magnet (about $4 for a 10-pack at home centers) to a piece of dental floss. Slowly drag the magnet across the wall surface. The magnet will “hang up” a bit over the nails used to fasten the wood lath to the studs.
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