Painting Over Wax

Q. I’m the manager of quality assurance for a custom store fixture manufacturer and we have a customer who sends us metal dress pattern cabinets to refinish. We must refinish them to meet the customer’s color specifications. These cabinets come to us in wax-coated cardboard cartons. The problem is that the wax on these cartons rubs off on the cabinets, and it’s very difficult to remove before painting. Most of the time it’s not visible and we don’t recognize the problem until after the new paint has dried. Naturally, the finish doesn’t adhere to the wax. We have tried wiping with different solvents, including a pre-paint cleaner given to us by our paint supplier. None of these solvents has worked well. Do you have a solution to this problem? Thanks for your consideration. C.M.

A. I believe this exercise has taught you two lessons. Paint does not adhere well to a waxy surface, and solvent wiping is a poor cleaning method. It is poor because, as you solvent wipe, the wax content in the solvent and on the rag increases.
Therefore, you are spreading the wax around as you wipe. It is also important to remember the health and safety issues involved with solvent wiping. If you must solvent wipe, apply a slow-drying solvent using clean rags or paper towels and change them often on each cabinet. Follow by wiping the still-wet cabinet surface with dry rags.

After drying, wash each cabinet using a hot detergent solution, rinse with clear water and dry thoroughly before painting. Another approach is using an emulsion cleaner to remove the wax, and then following through with the hot detergent, etc. as detailed above.