Thanks for your reply Larry
and great advice - I plan to use a grinder but its the thickness of groove that im unsure of.
I thought of putting two grinding discs in the grinder at once but this my be dangerious I would then get a groove thickness of about 6mm
What do you think
As the price of lead is expensive it seems the stepped flashing method has been replaced for just a single or double piece of lead.
I do understand that this is by now way the best but I can see where money comes into it.
In fact I have some flashing to do on my house and I was thinking...