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?

[Bilgin]

We studied the same question closely and results we had are:

1. Deposit Efficiency is increasing when the distance of nozzle to target is decreasing. Optimized distance seems to be 4 inches.
2. Overlapping areas of larger distances have more porosity and open to blackening under humid atmosphere.
3. Homogeneity of thickness is far better on short "nozzle to target" distances.
4. Speed of spraying is increasing with longer distances but the benefit is not comparable to the benefits of short distances.