On holes and screws.

[Enrique]

I must do a hole in aliminium to drive a screw into it. The screw is 3mm in diameter. That is, after the hole is done, I must make a an internal thread in it. And my doubt is, what diameter should the drill bit be? May be you know this or may give me some reference.

[Enrique]

I must do a hole in aliminium to drive a screw into it. The screw is 3mm in diameter. That is, after the hole is done, I must make a an internal thread in it. And my doubt is, what diameter should the drill bit be? May be you know this or may give me some reference.

I asked some people. It's all about getting a table where, for each screw diameter, there is tabulated the correspoding drill bit diameter.

[Enrique]

Problem solved. I took the piece to a turner's.