Hi im at work atm, and only got tapatalk to search the forums which is a bit crap. And im sure this has been asked before so please excuse me for asking again. I shall be heading to screw fix to pick up some hole saws after work, am i correct 140mm fans need a 152mm hole saw and 120mm fans need a 127mm hole saws? Im looking to get these two http://m.screwfix.com/p/bosch-progressor-holesaw-152mm/30231 http://m.screwfix.com/p/bosch-cobalt-holesaw-127mm/57699 Thanks
I'm not sure of the exact sizes you'd need, but surely they should be no big than the diameter of the fan?
You are not correct, no Fans are 120mm or 140mm square, so it's impossible for the diameter of the aperture to be more than that. I've just been measuring fans using my calipers and I get ⌀135mm for 140mm fans and approx ⌀115mm for 120mm fans. The actual impellers will be smaller still, probably closer to 130mm and 110mm.
Doh, dunno how i made that mistake not been thinking right. So glad i posted just to make sure. Thanks guys saved me some time tonite
This might perhaps be a bit late, but for very neat holes consider a Malco HC1. An example one on Ebay USA is item# 111880507270.
Thanks for the tip. Think i might go ahead and order one. But i need the hole saws for cutting fan holes into timber. My current project is building an AV bench to replace the crap ikea one we have
You probably already bought the hole saws but for people wondering in the future, I've found that 114mm (4 1/2 inch) hole saws are a safe bet for 120mm fans. Here in the states it's much easier to find a 4 1/2 inch hole saw for obvious reasons. It allows some slop, especially if you are using a hand drill as it will make a larger hole. You could go larger if you are installing C channel molding around the hole. I've not cut any 140mm holes but was just thinking this weekend I should buy an appropriate hole saw for it as I will likely need one soon. Doing some research it seems this size is rare but Amico sells a 135mm hole saw (as Lenny states) that would work. Or you can always just do it the old fashioned away if you don't mind some extra elbow grease to clean up the cut.
