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HVLP AP15 spray guns are fed with paint by syphon or suction from the paint cup. The air
flow through the air cap draws paint into the nozzle assembly, where it is atomised and
sprayed forward.
Mix the paint to the correct viscosity for spraying according to the manufacturers instructions,
and strain it into the paint cup through a fine mesh filter. When mixing the paint, ensure that
you have enough thinners to clean the spray gun after use.
Do not fill the paint cup to more than 3/4 full. Make sure that the top edge of the cup and
the cup sealing gasket are clean and free from damage. The cup locking lever must be
tightened firmly to prevent any leaks from around the cup rim.
Set the spray pattern and fluid flow using the adjustment screws on the spray gun. The
spray pattern is variable between round and fan by adjusting the air flow through the air
cap. Turn the spray width adjusting screw anticlockwise to increase flow and give a fan
shaped spray pattern, turning clockwise to close off the air flow will give a circular pattern.
The fan can be adjusted vertically or horizontally to suit your requirements by loosening the
knurled locking ring and turning the wings to the desired position. Set the fluid flow according
to the paint in use and the spray pattern by using the fluid flow adjustment screw;
anticlockwise to increase flow, clockwise to reduce flow. As the width of the spray is
increased, fluid flow will also need to be increased.
The air pressure needed will vary according to the paint in use, with thicker paints needing
greater pressure. For most paints, a pressure of between 22 - 43 psi is adequate.
To reduce overspray and to obtain maximum transfer efficiency, always use the lowest
possible air inlet pressure that produces an acceptable spray pattern.
The first requirement for a good resultant finish is the proper handling of the gun. The gun
should be perpendicular to the surface being covered and moved parallel with it. The
stroke should be started before the trigger is pulled and likewise , released before the
stroke is ended. This gives accurate control of the gun and material.
The distance between the gun and the surface to be covered should be 6 to 12 inches
depending on the material and atomising pressure. The material deposited should always
be even and wet. Lap each stroke over the preceding stroke to obtain a uniform finish.
NOTE: To reduce overspray and obtain maximum efficiency, always spray with the lowest
possible atomising air pressure.
Damage to the fluid needle or nozzle, or any of the air ports, will result in a faulty spray
pattern. Take care when cleaning or assembling these components.
When spraying, the gun should be held square to the surface being painted, at a distance
of 6 to 12 inches depending on the paint and atomising pressure. Keep the gun parallel to
the surface being sprayed, starting the stroke before pulling the trigger, and releasing the
trigger before ending the stroke. Overlap each stroke over the preceding stroke to obtain
an even finish. The paint cover should be even and wet when spraying.
If the gun is too far from the surface, or the paint is too thin, the paint will dry before hitting
the work, resulting in a rough, sandy finish. Allowing overspray to fall on a finished area will
also result in a rough finish. Too much paint feed or holding the gun too close to the work will
lead to runs and sagging.
USING THE SPRAYGUN
