The old timer at the lumber yard in Macon showed me how to read grain direction in 5 minutes
I was picking through a stack of 2x4s at a yard in Macon last month and this retired framer named Earl stopped me and pointed at the end grain on one board. He said "see how the rings curve like a smile? That board's gonna cup on you." I'd been building decks for 3 years and nobody ever showed me that. Now I flip every board and check the end grain before it goes in my truck. Anybody else got a quick trick like that they wish they learned earlier?