Screw diameter advice.

[JJ1]

Does anyone know of a chart or a set of guidelines please that indicate which diameter of woodscrew is best suited to which thickness of wood?

Thanks.

 

[Woodchips2]

Here's a couple of sites:

http://woodworking.about.com/od/joinery ... Length.htm

http://www.doityourself.com/stry/h2selectscrews#b

Regards Keith

 

[JJ1]

Thanks for the links to the two articles.

The second link mentions about using a No. 8 (4mm) screw for 3/4" thick plywood. Would this also be the correct size of screw for hardwood and/or softwood? That's the bit I'm never quite sure about. For instance if I'm drilling into 3/4" stock I was never quite sure whether I would be better off using a 4mm screw, 4.5 mm screw or a 5mm screw :?: :?: