What type of tool do you use to cut square holes for fans?

[custer]

I asked at work today and it was suggested to use a 'Roto-zip' tool. It's supposed to be similar to a dremel tool, but has a base like a router. Any have input? Someone here has to have experience salvaging old cases for rebuilt systems. I need to add at least 2 fans to this old case.

[Happy Joe]

As a metal worker, I would get out my pneumatic nibbler (cheap hand nibblers are availible, but kind of a pain to use). I have also used a drill and pneumatic body saw, a drill and a jig saw, a drill and aircraft snips, as well as a cut off wheel on a pneumatic or electric die grinder (very dangerous). For all methods protect the area well, with several layers of masking tape and rember to leave the corners for screw attachment of the fan to the case. Always use a file to get rid of sharp edges and meat hooks (your hands will thank you). For the most professional results cut the hole slightly undersize and bring it to the finish dimensions using a file or grinder. ALWAYS USE EYE PROTECTION.
Be careful and...
Enjoy!

[MJCfromCT]

i've used a drill with one of those big circular attachments (i apoligize to all the metalworkers for my knowledge of the lingo :) ) and it cut a perfect circle for the opening of an 80mm case fan. Then i just drilled the four holes for the screws and i was in business

[Johnny Fist]

I use a hole saw like MJC suggested. I found you'll get the best results if you place a pice of wood under the area that you cut. It will prevent the steel from pushing through and leaving large burs as it goes through the thin wall stock. If you have access to air or electric power tools, you can use sanding pads or a splt shaft to remove burs and leave a polished surface quickly. If you have the time and want to play it safe, then use a file to remove the burs and sharp edges.

[custer]

Thanks for the input, buds. :)
I work in a machine shop and have access to the bridgeports, etc.
And that's what I was thinking, just put a block of wood under the sheet metal and do whatever I wanted. But the tool and die maker there suggested this 'roto-zip' thing. It's what dry wall installers use to cut the whatever now and he tells me you can get carbide attachments to cut sheet metal with it.

This doesn't have to be perfect, but it's why I don't want to just start grinding with the dremel... it burns the paint and turns it black if I'm not careful. I'd like this to come out looking like someone who does it for a living would have it.

And I know all the suggestions here would work and with some care it would work ok. :t

[Vampiel]

One word.

Dremel

If you use it right, you wont even be able to tell it was cut. Ive used it many times, and the paint doesnt fly off. The only problem is if you wanted it to be smooth (no matter what way you did it) you would have to..

1. put rubber around the hole
2. sand it, that would cause the paint to 'fly off'

[Johnny Fist]

Hey, I work in a machine shop as a benchman. Put it in a bridgeport, and plunge the right size endmill through it. Chuck up a split shaft in an air grinder with the appropriate length 180 role paper to remove the bur and you should be done. Just be sure the wood under the case is clamped securely to the table otherwise...well, I guess you already know what can happen.

Forget the Dremels and silly home tools. Get the heavy machinery involved.

[TiGgErDbC]

i got a 15 pund sledge in the back. you just hold that side pannel up right i'll put a square attachment on the end of this here sledge... and wham-o, it will fit a 80m-120 mil fan with room to spare :r :x :r

[RamonGTP]

I've never drilled square holes in my cases, but I have drilled round ones several times with a whole saw bit.

[MJCfromCT]

I agree with Johnny, a bridgeport would make quick work of the job...then again, having a bridgeport in my garage and no access to a dremel, i'm a little biased :)

[Vampiel]

Dremel's are about $30.

[Johnny Fist]

Bridgeports are free if you work in a machine shop.

[MJCfromCT]

Originally posted by Vampiel
Dremel's are about $30.

...why go and buy a dodge neon if you have a cadillac you can drive? :)

[custer]

Ty, buds. I know what a benchman is, JF. Ur right, why horse around with kid's tools when ya got the whole world of 'doing it right' open to ya. Just plunge a starting hole and go with the end mills. The only prob is getting the ok for some government work.

[Johnny Fist]

Make sure you post some pictures when everything is done. I should take some pictures of the PSU I diamond polished a few months ago.