Tablesaw Blade Came Loose

Re: Tablesaw Blade Came Loose

Bill Tindall, E.Tn.

I failed to tighten the nut after the last change.

Correct

Happens easier on a grinder that has a wheel with more mass. I have had this event happen many times on a grinder where I didn't snug the nut sufficient. When the grinder spins up, inertia of the wheel resists rotational acceleration. Friction of wheel to flange to nut tightens nut. Grinding will appear normal. When machine is shut off the wheel decelerates and the process described above reverses. If nut is loose enough it will loose friction and unwind.

Thread's "handidness" is designed to tighten spinning things upon acceleration for a loose nut in this situation would be disaster-grinder, saw blade, lawn mower.

When installing a saw blade I pinch it between fingers and snug nut. Enough for my saw situation. If you need more, jam a push stick against the blade.

Thank You

Stuart Johnson

A stupid mistake I can live with knowing I caused it and have learned a lesson. FWIW, that is exactly what happened. It ran fine while it was running and just like you said it came loose when power was shut off.

Re: Tablesaw Blade Came Loose

Dave Bair

I did the same thing with a dado set except that I lost the nut and had the outside blade and two chippers come loose. One chipper cleared out the zero-clearance insert and the next one came flying out of the saw. Luckily, I ducked when the insert exploded, before the hardware went airborne. One of the chipper's teeth left a big gouge in the table top that always stares at me when I change blades, reminding me to really tighten the nut.

My father had opposite problem with his mower. He had on extra thick, heavy blades that would torque the blade nut down every time he engaged the blades. Because the blades and their nuts could not speed up to the mandrel's shaft speed right away, the shaft spun a bit and rotated the nut threads faster than the nut. When I switched to stock blades, the problem disappeared.