Cellulose and acrylic air-drying paints remain reasonably easy to compound and polish for a considerable time, but 2-pack materials are best compounded initially within a day or two of being sprayed. If left too long, they become very hard and, if flatted, make it extremely difficult to compound out flatting marks. This is even more so if power tools are not available. If 2-packs need rectification by way of compounding, it is best to complete the flatting and compounding stages as soon as possible after initial drying, even if fine compounding is left until later


Rectification of problems in the paint surface obviously depends on the depth of paint and the depth of the problem. Some will compound out without problem, whereas others may be embedded deeper in the paint film rather than simply stuck on the surface. Minor dust specks  or slight dry spray can be rubbed out manually or with a power polisher, using a medium grade rubbing compound.


By hand - Most types are applied with a damp cloth, rubbing with normal hand pressure in straight lines until the surface is smooth. Usually this leaves the surface slightly dull, but the gloss will be restored by using a finer grade of compound or polish to finish.
By machine - Damp the compounding mop slightly, and apply a small amount of compound to a section at a time. Use the weight of the polisher rather than press on, taking care on raised panel features. It is best to avoid corners or edges completely. Work a small section at a time, buffing regularly with a soft cloth until happy with the appearance.A hand spray filled with water is useful for keeping the compounding head damp.  Wipe compound spots from other panels before they dry.