Surface Treatments And Finishes

Two identical steel gates are hung on the same day. One was wire brushed, degreased, primed and given two coats of paint. The other was painted straight out of the workshop because the job was late. Both look the same on the day. Eighteen months later the second gate is lifting in blisters and rusting underneath, and the paint on it was the same paint. The finish did not fail. The preparation did.

This lesson takes surface treatments and finishes as the specification does: as preparation and application, applied to enhance functional and aesthetic properties. You will learn printing, embossing and ultraviolet varnishing for papers and boards; painting, varnishing and preserving for timber based materials; dip coating, powder coating and galvanizing for metal based materials; and polishing, printing and vinyl decals for polymers. Each one is a decision with a cost, and the questions on this topic ask which finish and why. This is the last of the nine specialist technical principles, examined in Section B of Paper 1, and it appeared on the specimen paper as a column of its own.