drilling

[jimmyrow]

Do u need a special drill bit for drilling acrylic? I know you do for glass

[redfishblewfish]

Nope....just regular bits / hole saws.

[jimmyj7090]

Regular holesaws work well, but keep it cool with water. It's also good to drill from both sides with a holesaw so the hole comes out a bit cleaner.

For smaller holes, standard drill bits will work, but they tend to grab at and crack the acrylic (and sometimes injure the person holding the acrylic). If the acrylic is clamped down on a drill press you shouldn't have a problem, but if you are using a hand drill or the material isn't clamped down it is a concern.

[madean]

you should get away with a standard hole saw bit. The ones that are for wood generally will also be rated for plastic as well. Also the metal cutting ones will usually cut wood and plastic as well. If you have the option go with the metal cutting blade. It should have more teeth and finer. If your trying to drill holes in an aquarium drill a pilot hole first, this will help guide your hole saw. Also I would suggest using hole saws that have pilot bits in the center. If you have been looking at hole saws you know what Im talking about. Looks like a drill bit attached to the center of the hole saw probably 1/4" drill bit. I would not reccomend using a hole saw without the drill bit in the center like a diamond tipped hole saw that is used for glass. I think I read somewhere that if you use a diamond tipped hole saw (for glass) to cut plexi, acrylic, or plastic- you will ruin the hole saw. Cutting from both sides is not a bad idea if it is practical. Do not try and rip through the plastic like you would cut wood. Take it slow and take frequent breaks. If the blade gets really hot and you continue to cut you run the risk of melting or altering the look of the plastic around the hole. It will look a little distorted. I had to cut 4 holes in a 1" acrylic aquarium recently and each hole took me over 45 min. I would cut a little bit then let the hole saw cool off and cut some more. Use a drill at low speeds and apply a little pressure, if you apply too much the saw will grab and the bit, motor will suddenly stop and the energy will transfer to the handle spinning the drill in your hands and depending on how tight you are holding the drill you can lose control of the handle fast. That sudden jerk can hurt your hands or your body if it spins around and hits you in the stomach or something like that. I am not trying to scare you just realize that the drill is very powerful and when it stops suddenly that energy has to go somewhere.
Just take your cuts slow and steady and you will be alright.
If your not drilling into an aquarium and just a sheet of plastic make sure the object as really, really secure. It can turn into a flying object faster than you can blink.