Arc Spray distance and parametera

[velocity]

Hi
In Tafa 18/5SS (55T) wire catalogue, gun distance from work is 3-4 Inces. My gun is 8830. So is it true or shoul i keep it as 8"?
Another question is for bond 95-5 and for build up with 420SS, whats optimum each layer thickness? Is it like Hvof or much thicker?
Also whats minimum 95 5 bond thickness for a healty build up for 2 mm?