Scale Models - View Single Post - Machining Small Counterbores for Cap Head Screws

alan2525 · 03-08-2007

I'm making some accessories for my Taig Lathe and wanted to counterbore some 5mm holes to take M5 Cap Head screws.

I thought I could drill a 5mm through hole and then counterbore it with a larger drill (10mm) to the required depth - but to clean up the hole so it has a flat bottom rather than buying purpose made counterbore bits with pilots - wondered about just grinding an old HSS Twist Drill square.

Can anyone offer any advice on how to grind the tool and advise if it's doable? Material would be T6 Aluminium HE30 6082.

03-08-2007	#1 (permalink)
alan2525 Scale Model Member Join Date: Aug 2006 Location: Essex, UK Real Name: Alan My Models: Anything that isn't worth throwing out Visit alan2525's Gallery Posts: 925 Images: 39	Machining Small Counterbores for Cap Head Screws I'm making some accessories for my Taig Lathe and wanted to counterbore some 5mm holes to take M5 Cap Head screws. I thought I could drill a 5mm through hole and then counterbore it with a larger drill (10mm) to the required depth - but to clean up the hole so it has a flat bottom rather than buying purpose made counterbore bits with pilots - wondered about just grinding an old HSS Twist Drill square. Can anyone offer any advice on how to grind the tool and advise if it's doable? Material would be T6 Aluminium HE30 6082. __________________