Oh, that's the case I want...

[Paul Hutch]

To avoid cracking and breakouts when drilling acrylic, buy plastic cutting drill bits.

Heh, OK, on to the shopping list. I will pop some vent holes in the bottom too - is starting with small pilot holes a good idea, or just increasing the risk with each hole drilled?

As long as all the bits in the series are plastic cutting bits there is no increased risk. I usually start with my smallest bit and work up to the final size when hole location is critical.

My experience over the past couple years is that no matter how badly I do a drilling operation the acrylic never chips or cracks with plastic cutting bits. This made me get sloppy last week, I needed four holes just a little bigger than my largest plastic cutting bit. Forgetting how bad it can be I grabbed a regular metal cutting bit for the final hole size and boom, it catches and makes a large chip on the hole edge. Used a hand reamer to enlarge the remaining holes so I've only got one ugly hole.