Electrocoat Dimensional Tolerances

Question:

My company makes high-tech precision machinery. Some parts are coated in-house. I am interested in using the electrocoating process on a metal part that needs to retain tight dimensional tolerances. I was wondering what type of tolerances the electrocoating process could hold when applied on metal parts. N.L.

Answer:

Electrocoating has evolved from a laboratory curiosity in the 1950s to a high-tech coating process today. One of its advantages is the ability to apply coating evenly to complex shaped parts. Another advantage is the ability to apply coatings with thicknesses that are even and consistent part after part.

I believe that a properly maintained electrocoating line, and most of them are, should be able to produce part after part with a coating thickness tolerance of one tenth of a mil (0.0001 inch). An alternative, if the part is fabricated from sheet metal, would be using pre-coated metal stock. However, tight dimensional tolerances are like beauty, which is in the eye of the beholder. Hopefully, one tenth of a mil tolerance in thickness is good enough for your application.