what size hole saw

[jswjimmy]

i want to make a 80mm hole into a 120mm . i know a 80mm is 3 inch but what is 120mm.

 

[beatle]

Well, it's definitely not 5 inches. Don't ask how I know.

4.72 inches (4 3/4) would be about right.

 

[jswjimmy]

thanks I will get a 4.75in, and a 3in in a week or two.

 

[RussianSoldier]

most hole saws say their metric length right on them...

 

[nimo]

Just take a CD and check
CD=120mm

 

[jeece]

Google The Wise says...

 

[Jagercola]

Actually, if you want it to flow with the fan blade, use a 4-1/2" hole saw. I'm pretty sure a lot of professional mod places use 4-1/2" also.

 

[THUGSROOK]

exactly,
the hole needs to be slightly smaller then the fan

120mm fan = 114mm hole
92mm fan = 89mm hole
etc.

 

[gnomepunk]

I dremeled my 120s in the lanboy. are you planning on using a hole saw for an alluminium case? or is it steel? I was going to get a hole saw and play w/ the dewalt, but the dang things were almost $50 at Lowe's for a 4.5".

 

[TStep]

1" = 25.4mm

 

[DJMiX]

easy conversion: my freind.. who says math isn't really usefull:


80mm = 3 in 3/80 = .0375 factor

.0375 x 120 mm = 4.5 in

120mm = 4.5in (this is for hole size not actual size of fan...)

actual size was given from the google magic calculator

 

[4dm]

Remember to make the hole even smaller than you want the final size to be. This way you can file the edges smooth. When you make a cut with a holesaw, expect jagged edges that can fall inside your case, cut you or your pet, etc. Plus a nice smooth hole is much more aesthetically pleasing.

 

[TitanDiddly]

Make the hole with a 4.5" holesaw, then file/grind/sand it out.