On 04/06/2021 13:09, Chris Bacon wrote:
I need 240mm M8 coach bolts (or roofing bolts). These do not seem to be
available.

If I use studding (threaded bar), how can I make a coach bold styne
domed head on one end?

Any other ideas? These to join concrete uprights of sectional building.

These do exist:

https://www.tcfixings.co.uk/product/...ed-din-603/557

But the usual suspect will only have 240mm in stock for M10 and M12.

What's wrong with studding, nuts and large washers? The fact there is a
square hole doesn't mean you have to use it.

Coach bolts can be difficult to remove once the head starts turning. As
I found out recently! :-(