WD-40 and Heavy Oil-Based Cutting Fluids

Question:

I need help with documentation on the problems with powder coating when an in-line fabricator uses WD-40 and heavy oil-based cutting fluids and the effect it has on my pretreatment and final results. B.G.

Answer:

Most cleaning systems should be capable of removing these lubricants, although they certainly seem like they are on opposite ends of the spectrum. The WD-40 is more of a rust inhibitor than lubricant. The product contains water-displacing additives in what is primarily a solvent base. The heaving cutting fluid would be much more difficult to remove, since it is thicker and likely contains other extreme pressure additives that further complicate removal.

It is imperative that both of these fluids be removed from your product prior to powder coating. If not removed, you will experience failures in your coating including: blisters, fisheyes and poor adhesion. Although the heavy cutting oil may be difficult to remove, it is not impossible. Contact your pretreatment chemical supplier for further suggestions if the current cleaner is not adequate.