FISHEYE PAINT DEFECT SKIN

If using a spray system, air pressure that is too low can cause uneven atomization and ultimately result in this effect.

Orange peel - This looks exactly what the term implies – an uneven, mottled appearance.

Prevention comes in the form of a well-maintained filtration system which scrubs any oil or moisture from entering the sprayer. This effect can be caused by entrained oil or water in the sprayer air system and is commonly seen when using shop air.

Fisheyes - These are small circular areas, highlighted by “craters” in the center, and are usually seen during spray application or shortly thereafter.

All of these situations can lead to bubbles in the top layer.

FISHEYE PAINT DEFECT SKIN

If the coating layer is too thick, if the coating goes into accelerated (heat) cure too quickly, or if the coating solvent evaporates too quickly, the coating surface may skin over while there is still solvent underneath that is vaporizing up. More bubbles and voids - The majority of bubbles are caused by a solvent that has been trapped, which ultimately vapors through the coating layers.If the operator is not extremely careful, the brushing action can entrain air bubbles into the coating, which results in the same cratering effect. Some bubbles collapse to create concentric rings in the shape of a crater (for larger caters, see “ Fisheyes” section below). As this air rises through the coating, it creates small bubbles. Air bubbles - Can be caused by a coating layer not leveling and adhering to the substrate surface, causing air to be trapped underneath.Ensuring adequate time between coats is a must. In this scenario, the solvent would not have had the proper time to flash off prior to the next coat. Another cause is insufficient tack time between coats. Proper cleaning can prevent delamination. Usually, you will only notice delamination after the part is out in the field, as it is not immediately observed in the majority of cases. Though there are a couple of common causes for this problem, one main cause is again a contaminated surface. Delamination - This is characterized by an area of the coating losing adhesion to the substrate, which can cause the coating to lift from the surface.Cleaning the substrate thoroughly prior to coating application will resolve this. Think of it as putting a drop of detergent in oily water – the oil immediately moves away from the single drop.

Dewetting can be recognized simply by observing areas of good coating application next to areas where the coating beads up and moves away from the contaminated area. The most likely culprits are flux residues, process oils, mold release, and fingerprint oils. Dewetting - This is caused by contamination on the substrate that is incompatible with the coating.Let's take a look at some of the more common problems that can crop up when applying and curing conformal coatings, potential causes, and associated cures. coating formula, viscosity, substrate variations, temperature, air mix, contamination, evaporation, humidity, etc.), it’s no surprise that issues come up frequently. Given the number of variables involved in a conformal coating process (e.g. One of the most common customer support calls we receive is about solving conformal coating application issues.

Fisheye paint defect