Putting holes in pots

[ArronOB]

I have a lot of repotting to do within a month - mainly cattleya and Oncidium alliance hybrids.

I like to use slotted pots - or pots with lots of holes for air flow. However I don’t have sufficient for this job and the costs here are prohibitive, so I’m considering buying a heap of basic black plastic pots and putting a stack of holes in them. Any suggestions on a quick and easy way to do this.

I’ve previously don’t this with a punch, or a soldering iron, but want something a bit quicker this time.

Cheers
Arron