Full disclosure: I’m actually embarrassed to say how long it took me to figure this one out.
I mean, talk about duh! Here’s the story.
There is one tool virtually every carpenter and DIYer has, and it’s a pencil. Nothing earth shattering there, right?
Of course, we use said pencil to write on our work: layout — 16 centers for framing, 5-inch centers for deck pickets, marking studs behind drywall to nail up chair rail and so on.
Every now and again (or more often than that depending on the kinds of day you’re having) a mistake gets made. You put the X on the wrong side of the line, read a 6 as a 9 and put a mark that doesn’t signify anything, or your stud finder is — as most are — wildly undependable.