On 29/05/2021 13:24, David wrote:
I need to cut a 30 mm hole in some 0.8 mm aluminium.

I have various hole cutting devices such as Forstner bits but they are for
wood.

Is there anything clever for cutting holes in metal sheets?

I used one of these: https://www.amazon.co.uk/gp/product/B07VYWBB1N last
week to drill 40mm holes into an alloy casting.