centerpoint of a circle

[noob with an RS 10+ year member]

or you can draw it out and use the perpendicular lines crossing method i learned in geometry. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[blue93corsica 10+ year member]

if its for a speaker ring, draw the outside diameter of the grill, then draw the inside circle of the grill, then put a dot through each hole in the grill for the mounting screw to go through, then ciss cross all your lines and where they all meet is the center point, then for cutting drill a 1/8" hole through and etc, well thats what i did for cutting out my circules anyway

 

[CBFryman2 5,000+ posts]

3 Aprox Diameter is easier than 2 Chords and a perpendicualr line, you dont need to know the circumfrence either way.