Help deciding what drill bit to use

[Proprietary]

This is my first time case modding... I have no idea what I am doing. How should I determine what drill bit to use if I want to drill holes for, say, a radiator? I bought a rotary tool set that came with drill bits of all sizes and shapes... 

[rEkmAInc1csBnlM6C85H]

If these are holes for mounting the radiator and its fans, check other existing holes for mounting fans on the case as they are usually the size of hole you want.

 

For spacing you can take cardboard, lay it over existing holes in the case and mark it or punch holes into it to get a template for spacing.

 

A quick google can yield templates and required hole sizes for the fan hole and the mounting holes, but make sure if you print it out the scale is correct https://mnpctech.com/pc-cooling-fan-templates.html

 

Because of the Nature of thin sheet metal a stepped bits will give you the best cut for mounting holes but is not necessary.

 

[iKingRPG]

20 minutes ago, Proprietary said:

This is my first time case modding... I have no idea what I am doing. How should I determine what drill bit to use if I want to drill holes for, say, a radiator? I bought a rotary tool set that came with drill bits of all sizes and shapes... 

usually pc parts use phillips #1 or #2

[Proprietary]

2 hours ago, Andrew 1337 said:

If these are holes for mounting the radiator and its fans, check other existing holes for mounting fans on the case as they are usually the size of hole you want.

 

For spacing you can take cardboard, lay it over existing holes in the case and mark it or punch holes into it to get a template for spacing.

 

A quick google can yield templates and required hole sizes for the fan hole and the mounting holes, but make sure if you print it out the scale is correct https://mnpctech.com/pc-cooling-fan-templates.html

 

Because of the Nature of thin sheet metal a stepped bits will give you the best cut for mounting holes but is not necessary.

 

I am doing a sleeper PC build with a case in need of tons of modding. What drill bit should I use if I know the screw going through it will be a UNC 6-32?

[rEkmAInc1csBnlM6C85H]

38 minutes ago, Proprietary said:

I am doing a sleeper PC build with a case in need of tons of modding. What drill bit should I use if I know the screw going through it will be a UNC 6-32?

1/8" give or take a 1/32"

[Proprietary]

14 hours ago, Andrew 1337 said:

1/8" give or take a 1/32"

how can I measure a drill bit's size accurately?

[Lady Fitzgerald]

16 hours ago, Proprietary said:

I am doing a sleeper PC build with a case in need of tons of modding. What drill bit should I use if I know the screw going through it will be a UNC 6-32?

Ideally, for a close fit, you should use a #30 drill bit. For a looser bit, you can use a #29 drill bit. However, since it's unlikely you will have a set of number bits, you can either use a 1/8" drill bit and work it around in the hole some to open it up a bit. Or you can use a 5/64" bit for a bit more clearance (pun unintentional).

 

1 hour ago, Proprietary said:

how can I measure a drill bit's size accurately?

Sometimes, the size of a bit is stamped or etched onto the shank of the bit. That can be hard to read on smaller bits. A much better way is to use a caliper to measure the diameter of the shank. Cheap digital calipers that are accurate enough for this can often be had for as little as around $35 in the U.S. (you didn't specify where you are from in your profile). Just make sure you get one that has metal jaws, not plastic ones.

 

15 hours ago, Andrew 1337 said:

1/8" give or take a 1/32"

Seriously? 

 

18 hours ago, iKingRPG said:

usually pc parts use phillips #1 or #2

Holy non sequitur, Batman.

[rEkmAInc1csBnlM6C85H]

2 hours ago, Lady Fitzgerald said:

Seriously? 

Yes.

 

There is nothing incorrect about my answer give or take tolerances, listed tools and user precision.

 

If you drill a 1/8" hole with a rotary tool it is going to be slightly bigger than 1/8" almost every time. Unless you can move your arm like a drill press.

[Lady Fitzgerald]

1 hour ago, Andrew 1337 said:

Yes.

 

There is nothing incorrect about my answer give or take tolerances, listed tools and user precision.

 

If you drill a 1/8" hole with a rotary tool it is going to be slightly bigger than 1/8" almost every time. Unless you can move your arm like a drill press.

You suggested using bits 1/8" give or take a 1/32". That's 3/32" to 5/32". 3/32" is simply too small for a 6-32 screw unless you are using a really crappy drill bit.  Even a good 5/32" drill bit will result in an ridiculously sloppy fit.

 

I've found using a 1/8" drill bit results in a fit that ranges from a hair too tight to one that a 6-32 screw will barely go through, even when using a portable drill motor or a Dremel type rotary tool (and I'm in my seventies with arthritis in my hands!). If you consistently get usable clearance holes for 6-32 screws with 1/8" drill bits, you are using really cheap, crappy drill bits, doing a lousy job of sharpening your own bits, or just have seriously sloppy work technigues.

[mariushm]

Or you could stop the madness and just use M3 standoffs (like used on 5.25" or like the M2 on M.2 SSDs )

[Lady Fitzgerald]

4 hours ago, mariushm said:

Or you could stop the madness and just use M3 standoffs (like used on 5.25" or like the M2 on M.2 SSDs )

And what would that gain?