Page No 2
Safety Rules when Using or Cleaning a
Spray Gun
Warning
Many fluids that will clean painted surfaces are very flammable and
the vapours should not be breathed. Always ensure that such
cleaning materials are correctly stored, used away from hot surfaces
and flames and cleaning takes place in well ventilated areas.
There are available special spray gun cleaning devices where the
spray gun may be partially or totally dismantled and the parts cleaned
within a container.
Smoking should be totally banned in areas where spray painting is
performed or cleaning takes place.
Use of spray guns should conform with all legislation relating to spray
painting.
Fire extinguishers should be readily available in the spray application
and cleaning areas.
All work stations must be provided with adequate ventilation to
remove any fumes resulting from the spray painting work and
cleaning process.
Paint flowing through hoses can create static electricity which if a
spark occurs could cause fire or an explosion. Such risks should be
eliminated by the use of “earthing” techniques.
Certain materials that can be used with spray guns may give off toxic
vapours that can be poisonous, irritants or create a general hazard to
health. The instruction supplied with any material should be carefully
read and understood before using the material. If such information is
not availabe -
find out
- never use if such information is not available.
Always follow the manufacturer’s instructions.
It is recommended that respiratory equipment is always used when
paint spraying and the type and efficiency of the equipment to match
the requirement of the material being used.
Use protective gloves when spraying and cleaning.
Use eye goggles when spraying and cleaning.
It is recommended that all operators connected with any aspect of
spray painting, including cleaning are fully trained by personnel
competent to train.
Certain solvents are in the category
“Halogenated Hydrocarbon
Solvents”
and these solvents can have a chemical reaction with
zinc plated, galvanized or aluminium parts and can cause an
explosion hazard particularly if the parts are under pressure. This
equipment as supplied is suitable for use with these materials but the
instructions supplied with the solvent must always be carried out.
Golden Rule
- Before using any equipment with “Halogenated
hydrocarbons solvents”
Check
that it is acceptable to do so.
Misuse
Never ever
point a spray gun in operating mode at any other
person. Make sure that the ejected spray from the nozzle never
comes in contact with any part of the body.
Never exceed the maximum allowed working pressure.
Before attempting to change materials or clean the spray gun
disconnect from the air supply and tip any unused material into
suitable containers, seal and store as required by legislation, i.e.
fireproof stores, etc.
Cleaning the Gun
It cannot be emphasized too strongly that the care, cleaning and
maintenance of the gun are of utmost importance. At the end of each
day or shift, the gun should be thoroughly cleaned.
Never
immerse
the complete gun in a cleaning solvent. This allows sludge and dirt to
collect in passages/holes within the gun which may eventually be
blown on to the surface being sprayed. Solvents also remove
lubricants from packings and cause the air valve and material needle
to stock.
The air cap/spreader should be removed and immersed in clean
cleaning fluid. If the holes have become clogged
never never
use
wire or other metallic devices to clean them. The small holes are
precision drilled to very close tolerances and any enlargement by the
abrasive action of metal will permanently affect and distort the spray
pattern when the only remedy is a replacement part.
Some additional advice is given in the following diagrams
(see page 7).
Dismantling & Assembly Instructions
Disconnect the spray gun from the air supply.
Remove the basic cup container by use of the cam lever on the top of
the lid and empty the contents of the cup into a safe, suitable container.
Such a container should be kept in an approved paint storage area.
Unscrew the lock nut on top of the cup lid assembly to remove the lid
assembly from the spray gun body.
Pull off the paint strainer from the body of the lid assembly centre tube
and unscrew the nut on the underside of the lid. It is then possible to
separate the lid, centre tube assembly, the locking cup arm and the
cam lever.
Take off the E ring (24) from the trigger stud (23) and re move the trigger
(21).
Unscrew nipples (6) & (19) from the spray gun body (5). Unscrew air
cap (1) and nozzle (2) then unscrew the nipple at the top rear of the
body (1) and remove the pattern adjustment assembly (7) complete.
Unscrew the fluid adjusting screw (18) and take out the needle (16)
packing holder (9) and O-ring (10) take off the fluid adjust guide set (15)
spring (14) air valve seat set (13 & 13-1) air valve seat set (12 & 12-1)
and gasket (11).
Plug (24) and packing (3) can now be removed from the air valve body.
Unscrew packing screw (8) and remove packing (9).
Reassembly
Clean all parts thoroughly to remove all traces of paint with suitable paint
removal liquids. Be careful when cleaning paint air cap (1), nozzle (2)
particularly from the small holes. Clean out holes using
wooden
cocktail sticks
or non
metallic toothpick
as any increase in hole
size, deformation or raising of burrs will change the spray pattern.
Carefully check packing (3) and (9) for paint contamination, splitting
and hardening and replace with other worn or damaged parts as
necessary. Replace parts with parts obtained from the manufacturer or
an authorised distributor.
Hints on Paint Spraying
Having selected the type of system/gun to be used and the paint to
be sprayed, it is important to make sure that the compressor has
sufficient capacity to supply the gun on a continual basis. As most
compressors deliver air with oil/moisture content and sometimes
small particles of dirt, it is strongly recommended that an air
filter/moisture remover is incorporated in the air line between the
gun and the compressor. Most compressors produce the
compressed air at 100 psi and above so the incorporation of a
pressure reducing valve may be necessary as most spray guns are
designed to work at between 30 and 80 psi with the average being
50 psi. The importance of this equipment cannot be stressed
enough as oil and moisture in the airline combined with over
pressure, can almost certainly lead to very poor contaminated paint
finishes.
It is important to remember that a spray gun is a highly efficient
compact and delicate piece of equipment. The care with which it is
used will pay dividends in the form of superior finishes and reduction
in rejects to the operator who familiarises himself/herself with its
possibilities and limitations. It is the daily routine cleaning that keeps
the equipment at peak efficiency, not the occasional attention of the
operator who only remembers when the desired finish is not
achieved.
Handling the Spray Gun
To use a spray gun efficiently, there are a number of very
important general principles and fundamental motions of