Blogger was unavailble for posting last night, so I hope all of you survived OK without your Monday Morning Grinder. I tried, but it kind of went like the video.
I'd always heard you were supposed to have your thumb on the same side of the crank as your fingers or you could end up breaking it if there was kick-back from the engine...is there anything to that?
True! On an engine with an impulse on the magneto like this tractor, there is very little danger. The impulse holds the armature momentarily, then releases it after the cylinder has passed top dead center. Model Ts had their magneto built into the crankcase, and you adjusted the timing with a lever on the steering column. Forget to retard the timing, and the crank will kick backward. It spins pretty quickly when it does that, so you want your arm to break free and pull out of the way. A broken wrist is the most common injury if your arm doesn't move fast enough. One of my uncles wrapped his thumb around the crank and a kickback pulled him down into the radiator, breaking his jaw.
When you run a chainsaw the opposite is true. You MUST wrap your thumb around the handle of a chainsaw to be safe.
I'd always heard you were supposed to have your thumb on the same side of the crank as your fingers or you could end up breaking it if there was kick-back from the engine...is there anything to that?
ReplyDelete-gsc1039
True! On an engine with an impulse on the magneto like this tractor, there is very little danger. The impulse holds the armature momentarily, then releases it after the cylinder has passed top dead center. Model Ts had their magneto built into the crankcase, and you adjusted the timing with a lever on the steering column. Forget to retard the timing, and the crank will kick backward. It spins pretty quickly when it does that, so you want your arm to break free and pull out of the way. A broken wrist is the most common injury if your arm doesn't move fast enough. One of my uncles wrapped his thumb around the crank and a kickback pulled him down into the radiator, breaking his jaw.
ReplyDeleteWhen you run a chainsaw the opposite is true. You MUST wrap your thumb around the handle of a chainsaw to be safe.