Cutting Fan Holes (How to?)

[FormatC]

I bought an old computer case from eBay an Enlight EN-7200 Desktop horizontal style case (Made in 1997 the first revision of the case) so it only has a front 80MM fan which I already cut out the stock grille as it was severely restricting of air flow. but the case has no back fan so I want to add one (I can only add one because it has knockouts for ports Serial SCSI Parallel ETC) I am limited to 60 MM fan size any bigger and it will interfere with the IO ports on the ATX backplate. I have several 60mm fans left over from the Socket A/462 Days and I also have the grilles to match them. So is the general idea just to trace the grille and cut a hole that size or do I make it smaller then the grille? I have a Dremel clone (A Black & Decker RTX) and I have plenty of cutting wheels so I'm prepared with tools. I know a holesaw is better but I'm cheap and I don't want to buy a tool I will use probably once plus my drill sucks.

It was suggested to me in another forum that I put a hole on the top or side (I can probably do a side hole or 2) but I have a support bracket in the middle so I can't any other suggestions for improving cooling in this old case are welcome

Here are pics of the back and support bracket so you can see what I have to deal with





Oh I bought such an old case for my HTPC because it has 3 5.25" bays (I could not find a modern case with 3 I have my DVD Drive and an Matrix Orbital LCD screen Which takes up 2 bays, I don't like the Built in VFD cases because most are only 2 X 16 my screen is a 4 X 20

[bubba]

Use the fan as a template to mark the case/or peace of paper. get a fine tip sharpie set the fan on the case where you want it. Then trace the inside diameter of the fan body on to the case, that will get you the right size hole for the fan. The use something sharp that will fit int he screw holes to transfer punch the hole pattern for the fan.

Good to practice on some scrap first, if you have any pads of paper that have the cardboard backing is good for this.

[stev]

A hole saw works great, but you need to run the drill slowly and apply easy pressure at first. PLUS, try to fixture the case and hold the drill really steady so it doesn't walk on the case surface (very important info). The hole will be done in under 60 seconds.

Remember to go slow, measure twice and cut. Like the eariler advice above, test out your drill skills and know how your drill behaves doing something like this. Not all drills are the same, nor are the chucks. A hole saw should give a clean cut if used wisely.

For hole saw fan sizes:

Fan hole requied and hole saw size based on Dewalt bits:

40mm fan = 1.5" hole saw
60mm fan = 2.25" hole saw
80mm fan = 3" hole saw
92mm fan = 3.5" hole saw
120mm fan = 4.5" hole saw with some drill bit wheel grinding if needed.

Why not use the 4.75 size for the 120mm? It's slightly too big. It can be fitted if used with a DIY gasket or ring.

[Apoptosis]

be sure to lube it up, so the hole saw cuts better... I use a dremel when it's done to smooth the edges down a bit and I also pre-drill the center of the hold to line up the hole saw first. This prevents and damage to the surrounding areas too.

[Major_A]

Another hole saw vote here. Make sure you pick up a bimetal saw and not something else. Don't lube the saw up too much or you might cause a fire. If you have access to a drill press you are in business otherwise you'll have to man handle the piece you are working with.