Volkswagen Golf Service & Repair Manual: Repair paintwork system for matt-finished vehicles

Issue 04.13

The repair paintwork system for matt-finished vehicles is outlined below. Area of use: larger areas/full painting operations

Application

Metal substrate

Plastic

Partial painting/full painting

Painting of matt-finished vehicles

Substrate

Suitable substrates:

Sheet steel

Cleaned and sanded electroplated or roller-galvanised steel panels or soft aluminium

Lightly sanded factory primer

Well-sanded factory paint or old paint (with the exception of thermoplastic paint)

Surfaces prepared with 2-pack polyester products and then finely sanded

Pretreatment/cleaning

Thoroughly clean with slow-drying silicone remover -LVM 020 100 A5- or silicone remover -LVM 020 000 A5-.

Repair paintwork system for matt-finished vehicles

Then, sand substrate.

Use a suitable cleaning agent to ensure a clean, residue-free surface prior to reworking.

Approved products

Filler:

2-pack spray filler -ALN 788 007-

2-pack IR premium filler -LSP 787 220-

Fine filler -LSP 784 002 A2-

Primer/primer surfacer:

2-pack primer surfacer for plastics, white/black -LKF 696 009/040 A2-

Glazed adhesion promoter -ALO 822 000 10-

2-pack wash primer -LHV 043 000 A2-

1-pack wash primer, light grey/dark grey -LVM 044 007/171 A2-

Surfacer:

2K HS Premium surfacer -LGF/LVM 013 ...A4-

2-pack HS Vario surfacer -LGF 786 004 A4-

Elasticisation:

Elastic additive -ALZ 011 001- (for all 2-pack HS surfacers used for plastic components)

Top coat:

2-pack HS clear coat -L2K 769 500 A5-

Matting

Matting additive -LVM 769 810 A2-

Observe the application instructions for the respective genuine products → Chapter „Genuine products“.

Mixing/matting of clear coat

Mix component A + component B (matting additive -LVM 769 810 A2- + 2-pack HS clear coat -L2K 769 500 A5-).

Mixing ratio:

Depending on the desired gloss level, the matting additive -LVM 769 810 A2- and the 2-pack HS clear coat -L2K 769 500 A5- are mixed at a weight ratio of 75:25% or 70:30%.

Note Stir or mix matting additive -LVM 769 810 A2- well in the can. Then, mix component A and component B thoroughly and do not add hardener and thinner until just prior to use. The ready-to-spray mixture should be applied immediately. If the mixture is left to stand in the mixing cup or spray gun cup for a longer period of time (15 min.), it must be stirred again prior to further application (sedimentation behaviour).

Addition of hardener to component A + B

4:1 by volume with 2-pack VHS hardener, extra slow-drying -LHA 009 053 A2-

Thinner:

2-pack thinner, slow-drying -LVM 009 300 A2-

Pot life:

Mixed for spraying, 60 to 75 minutes at +20 °C.

Method of application: “spray”.

Application viscosity 4 mm, +20 °C, DIN 53211

Application viscosity 4 mm, gravity-feed spray gun “Compliant” and “HVLP”

DIN 4 mm: 16-20 seconds

10 % thinner added if material temperature is +20 °C
Adjust spray nozzle following manufacturer's instructions to 1.3-1.4 mm for “HVLP”.
Adjust spray pressure following manufacturer's instructions to 2.0-2.5 bar for “compliancy”.
Adjust atomising pressure following manufacturer's instructions to 0.7 bar for “HVLP”.
Apply in 2 spray passes with a flash-off time of 10 to 15 minutes between the passes.

The specified thickness for the dry film is 70-90 µm.

Application:

To achieve the best possible and homogeneous matting effect, the following points should be adhered to during application: The spraying distance to the object is somewhat greater than the standard application in order to use the spray atomisation to its fullest effect. (Prevents streaking) If possible, making the two spray passes crosswise is also advantageous with horizontal component parts, such as the bonnet. When used on large objects, such as the vehicle's bonnet or roof, the featheredge of the 2nd spray pass is to be offset from the featheredge of the 1st spray pass. It must be ensured that »spray passes« featheredge evenly and an adequately wet spray film is applied. Application in excessively dry conditions poses the risk of clouding due to uneven flash-off or due to the spray mist not being absorbed. Where possible, the complete paintwork should be split into sections, i.e. the vehicle body is painted separately from the add-on components (hoods, doors etc.) in order to avoid featheredges and spray mist.

Drying:

Forced drying:

Final flash-off time 15-20 minutes

Drying time 45 minutes at +60 °C object temperature

Air drying is not recommended

Note

The gloss level that is actually achieved is influenced by a range of factors such as different hardeners, thinners, application types, drying conditions and layer thicknesses.

The recommended material settings must always be adhered to.

It is absolutely necessary to test the mixture (ratio of 75:25% or 70:30%) on a spray sample prior to application in order to achieve the gloss level that matches the vehicle. Interim steps are also possible.

Measuring the degree of gloss (at an angle of 60°) on adjacent parts may also be helpful.

Blending in or refinishing the matt clear coat within a component, e.g. a side panel, or Clever Repair is not possible.

Large-area paintwork (complete painting, roof, bonnets, side panel etc.) should not be carried out at higher temperatures (max. 20 °C).

It is not possible to polish dust inclusions, therefore cleanliness during the entire refinishing process is very important.

Personal protective equipment:

Adhere to the safety data sheet.

Wear personal protective equipment during application.

Repair paintwork system for matt-finished vehicles