1、MANUFACTURING STANDARDS p - GENERAL SPRAY PA.LNlUG MEPHOD FOR PRW AND ENAHELS -_ . 1. SCOPE Ine spray painting method for primers and enamels is a tried and proven technique which ensures that any overspray occuring falls on to a previously applied wet coat. Ihe purpose of this standard is to obtain
2、 a complete wet coat on the entire outer vehicle surfaces, betore any interior areas are attempted. Paint overspray is capable of being totally absorbed by a freshly applied wet coat, such that after baking it is non-evident in the painted surface. . If however, overspray is permitted to fall on to
3、dry surfaces, dry spray and surface irregularities will be evident after baking in the palutcd surrace. Poorly primed surfaces resulting from incorrect spray application may result in the primer film remaining porous after sanding and leading to primer defects such as “sinkage” which is visible afte
4、r enamel application. rhea spraying horizontal exterior surfaces, such as hood, roof or decklid, both operators should start at the same time, same place and spray siuultaneously in the same direction. Dy maintaining this technique deposits of overspray on adjacent areas can be avoided. Larger areas
5、 such as hood, roof and decklid should always be sprayed from the centre outwards. Outside edges and corners should be sprayed last. Carrying out this operation in reverse order i.e. edges before centre will almost certainly result in orange peel in tke baked film. interior surfaces must be sprayed
6、after the exterior as this is the only way to ensure that unavoidable overspray is absorbed by the wet exterior coat. The first coat of paint must fully cover the body and be of sufficient wetness to absorb overspray, Care should be taken to avoid sags and runs. 2. SPRAY GUN DISTANCE Spray guns for
7、non-metallic colours Should be held at a distance of apyrox 15U-21)omrU from the vehicle surfaces. This also applies to bclsc coal: metalllcs e-. un fncllaed from abars Fig 4 incorrect September 1993 i for reference only) PAINTING a!itBlD MANUFACTURING STANDARDS P Fig 5 (correct) Fig 6 The 7l.n ahow
8、n on pawe 5 and 6 deroamtrrta dlfformnt Rathod to bo applied for prlmr and rMlrprying XANUFACWRINO ADhllWSTl September 1993 (for reference only) PAINTING u-cx 8000 Page 5 MANUFACTURING STANDARDS 50 per cent overlapping of spray opsratiorls assures a good cover on the surfilce. Fig. 7 FIRST EXTERIOR
9、COAT This work may be performed as the first operation in.the spraybooth, an alternative would be to start with side panels, front lower and back panels- The operators commence spraying at the same time from the Fentre of the horizontal surfaces and spray towards the edges. (see para 1). Spray the r
10、oof without delay, followed by the luggage compartment door. In tllis manner, excessive drying of the overspray generated when spraying the roof is avoided. Care should be taken when spraying horizontal surfaces that the gan position causes minimal oirerspcay to the vertical surfaces. unpainted pain
11、ted ?4ANlJFAClURING ADMlNlSTRAllON U-CX 8000 September 1993 (for reference only) PAlNTlfjG Page 6 . !iaBB MANUFACTijRING STANDARDS P FIRST EXTERIOR COAT CONTINUED This operation may be performed following application to hood, roof and L-C-0. or alternatively as the first exterior operation. Spray all vertical surfaces with horizontal movements, ensuring a 50% overlap of coats. Spray the complete bodyside in one continous operation. . -.I unpainted L.-.-.-i painted MANUFACWRNG ADMlNtStRAlION September 1993 (for reference only) PAINTING U -CX 8000 Page 7