Torquing of lawn mowers

It's a lovely day. Birds are singing. Bees are humming. Grass is growing. Ah yes, the grass. I lugged my Honda mower out of hibernation, got it up on a bench (ouch!) and gave it a maintenance onceover, including removing the cutting blade thingy and resharpening it. I'm no slouch when it comes to tlc-ing inanimate objects, me.
Then I began to mow the back lawn. 'Orrible rattles. Arthritis, I thought, and carried on. Until a crash somewhere inside the guts of the machine gave me pause. I moved the mower, to find the cutting blade lying orphaned on the grass, no longer a part of its Honda parent. The thing is, my beloveds, when you tighten a nut, you have to really really tighten the bloody thing. My gentle torque had been nowhere near severe enough.
One day, when I grow up, I'm going to get the hang of machinery, women, digital clocks and videorecording. I guess it's just a matter of getting the torque right.