1. Adjust the coating with clean water to the viscosity of the appropriate coating, with the coating -4 viscometer measurement, the appropriate viscosity is generally 20 ~ 30 seconds. If do not have viscosimeter at that time, usable visual method: with rod (iron or wood rod) after stirring paint evenly, lift to 20cm height to stop observation, such as paint in a short time (a few seconds) constantly line, it is too thick; If the edge from the barrel is broken line is too thin; Want to be in 20cm high when just stop, paint fluid becomes a straight line, instant namely break flow becomes drop down, this viscosity is more suitable.
2. Air pressure is best controlled at 0.3 ~ 0.4 mpa (3 ~ 4 kg force/m2 cm). The pressure is too small, the paint atomization is bad, the surface will form the pitting; Pressure is too easy to hang, and paint fog is too large, both waste material and affect the operator's health.
3. The distance between the nozzle and the object surface is generally 300 ~ 400mm. Too close easy hanging; Too far paint mist is not uniform, easy to appear pitting, and spray nozzle far from the surface of paint mist on the way to cause waste. The specific size of the distance, class, viscosity and pressure to adjust the size. Slow dry paint spraying distance can be far, quick dry paint spraying distance can be close; When the viscosity is thick, it can be closer, when the viscosity is thin, it can be further away; When the air pressure is high, the distance can be farther, the pressure hour can be closer; The so-called near a bit far a bit is to point to 10 ~ 50mm between the small range of adjustment, if exceed this range, it is difficult to obtain the ideal film.
4. The spray gun can be moved up and down, left and right, it is best to operate at the speed of 10 ~ 12 meters/min evenly, the nozzle should be straight on the surface of the object spraying, to minimize oblique spraying. When spraying to the two ends of the material surface, the hand that pulls the trigger of the spray gun should loosen quickly, make the paint mist reduce, because the two ends of the material surface, often want to accept more than two times of spray, is the place that causes the most easily to flow to hang.
5 spray to the next pressure on the top 1/3 or 1/4, so as not to appear leakage spray phenomenon. When spraying quick-drying paint, it should be sprayed in a sequence. The retouching effect is not ideal.
The main points of the above coating, the use of high pressure airless spray machine equipment in the open outdoor spraying, to pay attention to the wind direction (when the wind is not suitable for operation), the operator should stand in the downwind direction, to prevent the paint fog has been blown to the spray film on the cause of ugly granular surface.
