A little write up from the BASF site....
On a freshly painted finish, craters (a.k.a. fisheyes, pinholes) appear when a contaminant that
creates high surface tension prevents the paint film from flowing over it. As a result, the paint
forms a ring around the contaminant, creating what looks like a circular indentation with
raised edges.
Sources of contamination that cause craters include: oils, fats, waxes, polishing and sealing
compounds, airborne oils and waters, and many types of personal care items such as
hairspray, deodorant and lotion. Only a very thorough chemical cleaning of the areas to be
coated can prevent craters from forming.
If craters have formed, sand away the contaminated topcoat layer, clean thoroughly, and
apply a fresh layer of material. Alternately, a fisheye eliminator may be used to lower the
surface tension and allow the paint film to flow over the contaminants. R-M makes two
products designed to reduce the effects of silicone contamination.
809 Fisheye Eliminator
Eliminates fisheyes without causing orange peel.
Use in R-M Clearcoats only.
Do not use in Diamont Basecoat or R-M Undercoats.
Add 2 oz. per gallon of RFU clearcoat.
812 Stop Silicone
Use in UNO-HD only.
Do not use in Diamont Basecoat or R-M Undercoats.
Add ¼ to ½ cap to one quart of RFU UNO-HD.
Apply 1-2 very fine coats in the areas where fisheyes have formed.
Allow solvents to evaporate between coats.
Please be advised that these products should be used as a last resort, and only when a
thorough cleaning of the substrate and spray equipment has not rectified the problem. If
used, all equipment should be cleaned thoroughly with clean (virgin) solvent-based cleaner in
order to reduce subsequent contamination.