Never use galvanised nails as slate rips will not cut them always use copper nails . At least 2.65x38mm
Ally nails dont last long, also try to use Stainless steel or copper straps, and use same metal for nails, to stop electrolytic action.
DD
Ally nails dont last long, also try to use Stainless steel or copper straps, and use same metal for nails, to stop electrolytic action.
DD