Hi, I've got a Black and Decker (approx. 20 years old) electric hover
mower with a metal blade that I want to remove as it has got badly
bent. However removing the blade is proving a little difficult.

The blade is held in place with a plastic (nylon?) bolt. I've tried
using the classic "Flymo" spanner (same size) on it but it broke (!).
Then I tried doing the same with an different spanner turning in a
clockwise direction. Logically, the bolt undoes clockwise, due the
direction of rotation of the motor, but I'm not sure if this is
actually the case. I didn't break a second spanner!

Then I tried mole grips on the bolt, and a length of scaffold pole
over the blade, and squeezed the two together. This resulted in the
blade turning on the shaft, and the bolt staying put.

What do you reckon I have to do to remove it? I am reluctant to wedge
anything in the motor itself, as the casing is plastic, and I suspect
it would just crack. I *could* try holding the plastic fan thing (I
believe it is known as an impellor) just under the blade, but this
doesn't look too strong either.

I'm thinking about just hacksawing off the bolt and dealing with the
aftermath later. What do you reckon?

Thanks

Luke