Five years back, I'd spend 20 minutes hand-twisting and taping BNC connectors on a bench in the hangar, praying they'd hold. Then a senior tech in Anchorage saw me and just tossed me his ratcheting crimper, saying 'Stop wasting your life.' I still keep that old tool in my box as a reminder. What's the one piece of gear that saved you the most time?
My old mountain bike needed a headset bearing preload set to 25 Newton-meters. Tried guessing with a regular wrench and nearly ruined the threads. Now I use a torque wrench on my bike pedals, seat post, and even my desk chair when it gets wobbly. It saves so many parts from getting stripped out.