I dont have a compressor. No space for one really, although i was thinking of getting one of those small portable ones and sticking it in the shed when not used.

Anything run off the mains would be ok. Even nicer if a decent battery powered jobby existed. I borrowed a battery angle grinder once and it just didnt have the onions to cut through 2mm steel. Plus battery lasted so short a time to be almost useless. that was a few years ago though.