Edge marking

Visible edge marking/mapping of the old paintwork in the paintwork surface or body filler or filler spots.

Causes

Insufficient drying of filler spots and/or body filler spots
Solvent-sensitive layer on sand-throughs in the old paintwork. The transition areas of the layers in the old paintwork, from the body filler to the old paintwork or from the old paintwork to the body panel are not sanded down finely enough
Solvent-sensitive factory-primers on new parts
Wrong amount of hardener
Insufficiently sealed sand-throughs when using a basecoat/clearcoat system (swelling of the basecoat)

Adhere to recommended flash-off times. Drying with infrared equipment will prevent edge marking/mapping of the paint film as the lower paint layers are heated first.
Before painting, carry out a solvent-resistance test with acrylic and/or NC thinners. Sand transition areas carefully (body filler with P80/P150, primer filler/filler with P240 according to technical data sheets). Do not apply body filler to old solvent-sensitive paintwork (leave a bare metal transition area). Apply filler in thin coats (for sealing) and allow longer flash-off times between coats. Use products with mild solvent properties (e.g., Glasurit water-thinnable 76- 1K Primer Filler.
Keep to indicated mixing ratios.
Seal sanded-through basecoat layers with primer.

Thoroughly sand down affected areas. Refinish using the suitable undercoats and/or topcoats.