(1) When spraying, the distance between the Spray Gun and the spraying surface should always be kept at about 20cm. It is intuitively expressed as the distance between the thumb and little finger when the five fingers are spread apart. If the humidity is high, it is necessary to reduce the distance. Remember, however, that if the spray distance is too short, the velocity of the spray air flow will be high, which will cause ripples in the coating. If the distance is too long, too much solvent will be evaporated, causing an orange peel or drying of the coating, and affecting the effect of the color. Using a slow evaporation thinner makes Spray Gun position less critical, but spraying too close can result in flow. Spraying too far away can result in wasted paint due to the formation of stray spray.
(2) The gun should be held horizontally and perpendicular to the spraying surface. If the angle of the Spray Gun is not correct, it will cause uneven paint film if the arc type swing spray is used. This is impossible to avoid completely in practice, but special care should be taken in operation. On a flat surface like spraying a car roof, the Spray Gun should be pointing straight down.
(3) When spraying, the Spray Gun should first open the first-stage air switch of the trigger, then move the gun and pull down the second-stage paint switch of the trigger, and release the paint trigger switch before shutting down. Only in this way can the transition be smooth and avoid big ups and downs.
(4) Do not swing the Spray Gun in an arc when spraying, and the movement of the Spray Gun should not be curved, otherwise the paint film will be uneven. The only time you can turn while spraying is when spot spraying requires the edges to be thinner than the center.
(5) The speed of the moving Spray Gun should be kept at a constant speed, running at a speed of about 20cm/s~30cm/s. If the Spray Gun is moved too fast, the coating will be too thin; if the Spray Gun is moved too slowly, flow coating will occur. The speed needs to be steady, otherwise uneven coating will result. Do not stop in one spot to spray, or the coating will drip and form a sag.
(6) Release the trigger when the Spray Gun reaches the end, and then pull the trigger when you start to go back. That is to say, when turning around, you should first release the trigger and then pull the trigger. This helps avoid flow coating, reduces excess spray, and saves material. The correct operation of pulling the trigger is divided into four steps: ①Start walking on the cover paper, pull the trigger halfway (first stage), and only release the air; ②When you reach the edge of the spraying surface, pull the trigger completely, spray ③When walking to the other end, release the trigger halfway; ④Go forward for more than 20 centimeters before turning around, and then repeat the above operation.
(7) Difficult-to-spray parts like corners should be sprayed first. Aim directly at these areas to evenly coat both sides of the flat surface. The spraying distance should be slightly closer than normal, or the spray control knob should be turned in a little. If it is closer, the moving speed should be faster to keep the paint film thickness normal. Once you've painted all the corners, it's time to start painting the flat or nearly flat parts.
(8) When the spraying surface is very narrow, the Spray Gun or air cap with a smaller spray pattern should be replaced, or the semi-air pressure, spray volume and spray width should be appropriately reduced.
(9) Generally speaking, start from the very top, such as the roof of the car. The nozzle of the Spray Gun should be level with the top of the plane, start spraying from one side of the roof, transfer to the central part, and the operator transfers to the other side of the car to continue spraying from the middle.
(10) When turning around, the nozzle of the Spray Gun should be aimed at the lower position of the previous stroke. 1/3~1/2 of the spraying area should overlap with the previous stroke.
(11) When the whole vehicle is continuously sprayed, there should be a partial wet overlap with the area sprayed last time. Care should be taken when handling to avoid thick coating or sagging at the barge.
(12) Continue to operate back and forth, release the trigger every time you go to the end, and reduce the spraying width by half.
(13) In the last pass, half of the spray should be lower than the sprayed plane. For the door, the second half of the spray is shot empty.
(14) The above steps are for single coating. For double coating, repeat the above operation. There should be a period of rapid evaporation between the two coatings, that is, the time required for the solvent to evaporate to make the coating slightly dry, generally 5min ~ 1Omin. This can be observed with a slight matte appearance of the coating. The spraying of solid color paint is usually 2 to 3 single coats, while the silver base paint needs to be sprayed with 2 single coats and then sprayed with mist spray again, and then sprayed with 2 single coats after standing for about 20 minutes of varnish.
