Caring for Your Spray Gun
Caring for Your Spray Gun [18.10.10]
(From DeVilbiss Service Bulletin SB-2-001-F)
Cleaning, basic maintenance and lubrication
Remove the air cap from the gun and immerse it in clean solvent. Blow it dry with compressed air. If the small holes become clogged, soak the cap in clean solvent. If reaming the hole is necessary use a toothpick or some other soft implement. Do not clean holes with a wire or similar hard object, as permanent damage can be done resulting in a defective spray pattern.
Cleaning a Suction or Pressure Feed System
Turn off the air to the gun, loosen the cup cover and remove the fluid tube. Holding the tube over the top of the cup, pull the trigger to allow the paint to drain back into the cup. Empty the cup and wash it with clean solvent and a clean cloth. Clean off the outside of the tube. Fill halfway with clean solvent and spray it through the gun to flush out the fluid passages. Then remove the air cap and clean it as previously explained before replacing it. Wipe off the gun with a solvent-soaked cloth, or if necessary, brush the air cap and gun with a fibre brush using clean-up liquid or thinner.
Cleaning a Pressure Feed Gun With Remote Cup or Tank
Turn off the air supply to the cup or tank. Release material pressure from the system by opening the relief valve. Material in hoses may be blown back. The lid must be loose and all air pressure off. Keep the gun higher than the container, loosen the air cap approximately 2-3 turns, hold a rag over the air cap, and trigger the gun until atomizing air forces all material back into the pressure vessel.
Back-flush the hose into the cup or tank with solvent and dry compressed air. Clean the container and add clean solvent. Pressurize the system and run the solvent through until clean. Atomizing air should be turned off during this procedure.
Clean the air cap, fluid top and tank. Reassemble the system.
Note: Never soak the entire gun in cleaning solvent. This will dry out the packing and remove lubrication.
Lubrication
Lubricate (daily) the fluid needle packing, the air valve packing, the trigger bearing screw and the adjusting screw threads with spray gun lube. The fluid needle spring should be lightly coated with petroleum jelly. Thoroughly clean the air cap and baffle threads and lubricate with spray gun lube. Lubricate each of these points after every cleaning.
Parts replacement
Always refer to the exploded view of your gun.
Pull trigger or remove fluid adjusting screw prior to tightening the tip to avoid damaging both the tip and the needle. Spray guns have some combination of plastic, copper, leather and soft packings and gaskets. It is recommended that these be replaced if the assembly is removed or when dong an overall repair. The fluid needle packing must be replaced when the packing nut bottoms out. New packing or needle should be oiled before assembly. Packing nuts should be tightened just enough to seal. Too tight will bind the needle as well as shorten the life of the packing. When replacing the fluid tip or fluid needle, it is recommended that they both be replaced at the same time.
Please let us know if Columbia Industrial Supplies can answer any questions you may have or if you would like further information about the paint spraying equipment we stock.