how to drill acrylic

my dad and uncle tomorrow are drilling a 1/2 inch hole into a 40 gallon 1/4 inch thick acrylic fish tank which is a 3 yr old saltwater tank full with water and fish. It is a cube and has the built in overflow filter system. i could empty the place where i want to drill the hole in the back of the tank so my question is can i drill the side of the tank without emptying the tank and flipping it on its side. if i dont have to do that, how should we prepare the area to prevent cracking? i have heard of spraying water, taping the other side, putting wood on the other side, ext but i wanted your expert opinions from maybe your experiences as well. Any suggestions would be greatly appreciated.

 

when you drill the side the water will come out of the hole then it will be hard to get a bulk head and every thing in idk if i would do it i would empty it

 

no i can empty the back of the tank where i will be drilling, the tank is divided into 2 sections and i can empty the filter side without emptying the main tank water.

 

Its acrylic, I don't think acrylic cracks.


nvm: I'm wrong they can crack too, I still think you would be safe if you emptied it a good many inches below the place you want to drill. I have only drilled glass btw.

 

Go slow if you get the bit spinning to fast you will melt the acrylic even if you have water to cool it. If you have small pieces of scrap laying around I would recommend practicing first. You need to keep the drill very straight otherwise it will bite into the acrylic and crack the tank. I used tape on both sides of the tank I drilled. Also it helps to drill a pilot hole otherwise a larger bit will walk across the tank before it starts to drill.