Tapping a Thread

[Avocet]

A lot depends on how the finished tapping will be loaded, but I wouldn't get too hung up on using the right drill to be honest. I agree with Puff. For your genoa car, I imagine the bolt that goes in will be loaded largely in shear. I'd go in with a 7mm dill and not loose too much sleep!

 

[alec]

Just a vote of thanks to everyone who contributed.

The taps worked out very well. The stainless tap's were an interesting challenge but turned out ok.

I would like to have owned a drill press as it's not easy keeping things straight but it was good enough .

Enjoyed doing it and saved money - Thanks Again.

 

[TheBoatman]

Clive
My Zeus book is approaching 40 years of age and still going strong. I don't need to use it so much these days but it's travelled the world ~ mainly in my boiler suit top pocket?

Peter.