Drilling holes in acrylic sheet is easy with a small modification to the cutting edge of the drill. You should then have clean holes with no cracking in the acrylic.

I don’t subscribe to this view as it is already difficult enough to grind the cutting edge of very small drills without having to alter the included angle as well. I use standard drills and just “blunt” the cutting edge as shown later.



Make sure you wear eye protection and a face shield in this operation.
It is also possible to “touch” the cutting edge on a fine bench grinding wheel provided it has sharp corners but the Dremel is best for tiny drills. This photo shows a diamond impregnated disk but a normal brown abrasive disk will work (with a face shield). Do both cutting edges on the drill.
I always use a magnifier to carry out this operation.
Here is an interesting link from an Aussie Plastic Fabricator on how a pro sharpens his drills and other tools for plastic.