Countersink angle?

[kaseryn]

I need to countersink some hinges to better fit standard zinv pz wood screws... so should that be 90deg (steel)?

 

[big-all]

yes 90%
possibly no7s and a good fit into the hinge pocket

 

[kaseryn]

Cool thanks

 

[big-all]

most people don't even realise theres a no7 screw but lots off door and window furniture will use this size

 

[Deleted member 174758]

Hiya B-A. Not a lot of people realise it any more but an engineering countersink is generally 90° (BSW, metric, etc), a wood screw countersink should be 102° (or flatter) to sink the screw properly (assuming it's a traditional screw)

 

[big-all]

Hiya B-A. Not a lot of people realise it any more but an engineering countersink is generally 90° (BSW, metric, etc), a wood screw countersink should be 102° (or flatter) to sink the screw properly (assuming it's a traditional screw)

aahhh the point angle i assumed in relation to square

 

[Deleted member 174758]

Yep. I've seen it on boats where people have replaced British brass or bronze screws with American Robertson (squate drive) self-tapping type screws which never bed properly in the countersink because they are engineering screws.