On Oct 16, 4:38 am, "mo" wrote:
I have:
....
A sheap electric saw from Argos with a 'metal' cutting blade

Try this in the 'waste' part of the metal you don't want, use some oil
or WD40 to cool the blade and stop it going overheating and going
blunt.

The ideal way would be a small grinder with a slitting disc in a
grinder stand.

cheers,
Pete.