Bill wrote:
On Sat, 19 May 2007 19:00:28 +0100, Davy wrote:

I am servicing a Hayter Hayterette mower and need to remove the large metal
disc that the bladelets are attached to so that I can replace them. I
assume I undo the nut in the centre. But how to stop the disc/shaft
turning?
And does anyone know which way the disc rotates in use - I suspect that the
bladelets are on the wrong way round!

cheers

Davy
Any nut securing a blade on a rotating shaft,
that is a saw,a grinder, a lawnmower blade
holder, is designed to tighten up under rotation.
Otherwise they'd be flying off everywhere.
So, think about it, when the blade is rotating
the nut is tightening in the opposite
direction.

So mark the rotation with a chalk arrow on the
blade holder. Lock the blade holder somehow,
clamp it to something.
Turn your spanner in the direction of the arrow
to undo the nut.

They are *******s to undo. My mate who is a
lawnmower mechanic uses an air rattle gun.
Give it a blast of penetrating oil.
Get a good fitting solid spanner.
Try a lever on your spanner, or belt the spanner
with a lump hammer.
Failing that belt the nut round with a lump
hammer and cold chisel.
On grind a section off the nut and while it is still
hot, belt it with the lump hammer and chisel

Depending how solid you have it, it could be
a piece of ****. Then again you could bend
your shaft, but that's part of the fun of DIY
innit?
Regards
Bill

I've never failed to get the nut off OK. Mole grips on the disc and a
2ft bar on the socket set.

On account of the woodruff key they don't tighten up that much.


But the disk has usually stuck to the point where I decoded to attach
blades in situ...

The key is the key IYSWIM, rusted in place.