Cutting 120mm holes in case?

[Grov]

In preperation for mounting my Dual heatercore, im thinkin of grabbing a holesaw.

Found this site:http://www.shop4tools.co.uk/acatalog...lesaws_35.html

But there's no 120mm exact size, so what size would i need? 114mm or 121mm??

Also how do you guys mod your cases? Iam after a really decent finish.

[cAsio]

u have to choose the size of the fan rotor
, the fan is 12x12cm not the rotor the hole must have the size of the rotor

[Grov]

Yeah thinkin about it the whole fan is 120mm, so the actual shape of the hole is gonna be smaller, so iam after a 114mm then?

[cAsio]

that i dont know sry

[humanoid]

The "propeller" is bigger than 114mm... you can buy the 114mm and whet to desired size. Or you can buy the 121mm one, but than you'll have a bigger hole, so there will be some space between the propeller and the case cover. If you plan to do that with this tool, than i would go with the bigger one (121mm). But you can use a dremel or sth else instead to cut the hole

[Rocket]

I never had much luck cutting case holes with a holesaw...
The metal was just to thin....made a mess.
I ended up marking the hole and cutting with a jig-saw.
then took the dremel with a round drum type sander to clean the edges.

[humanoid]

When you cut with the holesaw, you have to clamp a wooden plate with the case cover and then cut

[Direkt]

When you cut with the holesaw, you have to clamp a wooden plate with the case cover and then cut

So clamp a piece of wood under the place you are going to cut the hole? Is that what you are saying? So that way the hole saw will go into the wood afterwards instead of popping out and jumping around like crazy? If this isn't what you are saying, would you mind explaining it to me again =).

[illmatik]

Yes, the wood underneath will reinforce and stabilize the thin case metal so that you get a clean hole that can be polished with a file or dremel.

[illmatik]

I also like to punch or drill a small center pilot hole for the arbor to catch before I use the hole saw. I find it helps to keep the hole saw aligned properly so you can give the drill more rpms without the saw jerking or sliding.

[humanoid]

Like illmatik said, the point is to reinforce the case metal... so the piece of wood has to be large and massive, not a thin 150×150 pieces.
You can also drill a pilot hole, like he said. I only have the hole-saw that also has a center drill, so taht is not necessary

[Maximus]

A 3 1/2" hole saw works just about perfect...no idea what that is in mm....

[illmatik]

My hole saw has the center drill as well, I just find that a lot of the arbors out there skip around on the polished metals most cases use and the small pilot hole or indentation grabs the bit a little better.

[Direkt]

A 3 1/2" hole saw works just about perfect...no idea what that is in mm....

I think you might mean 4 1/2" which is 114mm. 3 1/2" would be quite small for a 120mm fan.

[freecableguy]

4.5" hole saw is damn perfect for the 120mm fan. The hole cut out EXACTLY matches the size of the interior of a 120mm fan.

[Jupiler]

114mm would be fine, that's what I use anyway.
The chassis of a fan is about 2mm thick.
So 120 - 4mm = 116mm (a 120mm fan grill is 116mm actually).
A 121mm saw would be a little to wide, 114mm is better IMO.

[Ad Rock]

114mm is what I use as well, it fits almost perfect.

[Navig]

Here are some pics to give you an idea of how it goes.

This is me giving some tips on cutting thru polycarbonate/acrylic, but the same principles apply to thin metal.

navig

[Grov]

Bloody hell. With thr arbitar thing it's nearly £30, no way iam paying that, is there no other way.

[Reflex1]

i have cut a 120mm fan hole in my lian-li and also in a cheapo steel case ...what i do is drill lots of little holes around the circle and then file the rest off (this is easy on aluminium cases ...as aluminium is soft to file down).

use a regular CD (compact disc) as a 120mm stencil.

[Ugly_Jim]

i have cut a 120mm fan hole in my lian-li and also in a cheapo steel case ...what i do is drill lots of little holes around the circle and then file the rest off (this is easy on aluminium cases ...as aluminium is soft to file down).

use a regular CD (compact disc) as a 120mm stencil.

How long did this take you? And did you have to clamp wood to the aluminum lian-li?

[illmatik]

yeah, use clamps. on the case i did it on the top came off, so I just placed the wood underneath and drilled really slow

[illmatik]

Well not too slow.. need to keep the saw at a constant speed, but going too fast will just rip the metal rather than cut it

[d3birth]

Nothing is worse than going too fast and totally screwing up your case.

[MONSOON]

2 words for you.
CD and Dremel
Thats what I used to put mine in, just lay em out so theyre square with one another and spaced equally apart and away you go.