Advise please

[Lunchbox]

ok, Buying a case with window on the side already, and it has a 80mm fan on the window. I wana make the whole bigger so i can put a 120mm fan on instead.
Any suggestion on what to do to amke the hole bigger.
Cut it?
Sand it?
someone tell me please

Oh and i guess I'll need to drill new hole to hold it in place, tips on that please aswell

[fragged]

Sanding it isnt probabble, unless your happy to finish it in a few years time

Your best bet (afaik, failed tech in year 9) is to use a drill with a 12cm ring hole bit, you know those ones that drill out the guts and leave a nice neat hole (that then needs to be sanded down etc) I'm not sure if the drill hole pieces come in 12cm sizes, but if i were extending a hole that'd be what i'd do...

Make sure you know the diameter of the fan, 12 cm fans are 12x12cm including the plastic OUTSIDE the fan, so if you cut a 12cm hole you'll simply be able to push the fan through instead of making it stick there :p

[AKA_RA]

actually, its a 12cm hole. the diameter of the hole is as wide as the fan, yes. but as you stated the fan is 12cm x 12cm. that means its relatively square shaped. unless you cut a square shaped hole you dont have much to worry about pushing it through the hole.
anyways, yeah, i agree a hole saw would work best. you just need to carefully clamp a peice of wood to the side panel. theres a drill bit in the middle to hold the holesaw steady and if theres already an 80mm hole it wont have anywhere to go.

[EPYK]

if you have one of those drill bits that cut big holes... then you could use that.. put your wind on a board or something... and then sand the edge with a fine grain sandpaper

[ajmilton]

something else you could use (possibly) is called a knockout punch ... sounds like a mike tyson video game, but basically its designed to cut metal circles by tightening a nut on what's basically a couple of circular metal chisel sort of things - they're fast, pretty safe, and will go through a computer case no problem :p

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=91201
^^example

local hardware store should carry 'em, or if you know anybody that does metalworking