Im sorry guys the only tapping I know is with my hand home made jig to keep the tap straight because I am **** at doing it by hand. Honestly I am terrible at it. Normally off to one side. Not much better with a batt drill.

I am buying a cheapish auto tapping arm. M3 to M16 and M10 is about as big as I will go. I do use a lot of fasteners in my designs I guess its the aircraft engineer in me liking a properly spaced line of rivets ha

I am in New Zealand. Ive been offered a nice little unit but have been offered chucks with the arm in JIS, ISO or DIN. All I can find is these are different standards correct? I guess I just need a push in the right direction. Or, does it not matter they are all about the same and will be able to accept most commercially available taps? Wow never thought I would have to write something like this. Help please guys. Rgds