The holes for a pop bottle bong

Hi .. im just wondering what wud be a good idea to make biro pen sized holes on a pop bottle. I saw a guy use a cigerette.. but i dont have any. Any thing i cud use ?

Here's how I do it. Just take a lighter and heat up the bottle where you want the hole, keeping a careful eye on the melting plastic. A few seconds after that, a hole will form in the plastic where there is the most heat. As soon as you see this hole, plunge the pen tube into the bottle at the angle you want it. With any luck, the plastic will resolidify around the pen, and any minor air leaks can be fixed up with gum or tape.

Ok ive done that but one problem my shit is grinded. Im just thinking if i put it in the cone i made wont it just fall through.

use foil with really tiny holes

You could also double layer the tinfoil, so that the holes in the layers don't match up. It could end up a smidge harder to hit if you don't do it perfect, but it always worked for me for smoking shake.

I heard using tin foil fucks up your lungs really badly....i dont know i think i read it somewhere

yea just get double layer tin foil and then use a safety pin of a sewing needle to poke a bout 5-10-20 holes depends on how big the tin foil bowl is. but before u do taht u should form the tin foil in the pen for the bowl and then poke the holes. and then like someone said just use gum or tape to fix and air leaks. and there ya go a perfectly made bong.