MIL-HDBK-1110
Figure 17
Illustration of Proper "Triggering" of Spray Guns
c) Distance. Distance between the nozzle and the
surface being painted depends on atomization pressure and the
amount of material delivered. This distance usually varies from
6 to 12 inches for conventional spraying and from 12 to 15 inches
for airless spraying. If spray gun is held too close to the
surface, heavy paint application and sagging or running may
occur. If the gun is held too far away from the surface, a dry
spray with a sandy finish may result. Such paint films usually
contain holidays (small holes) and provide an unacceptable
surface.
d) Corners. Both inside and outside corners require
special techniques for uniform film thickness. Each side of an
inside corner should be sprayed separately as shown in Figure 18.
Too thick a layer of paint can easily be applied to an inside
corner. But when too thick a layer is applied, the coating may
shrink or pull away from the inside corner causing a void
underneath the coating. This will lead to premature failure. An
outside corner is first sprayed directly, as shown in Figure 19,
and then each side is coated separately. On an outside corner,
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