Powder coating is a process that creates a permanent, baked-on paint finish on an item. A specialised powdered paint is sprayed on an item, and then the item is subjected to high heat. The heat melts the powder, which then forms a solid, hard, paint-like finish. Because powder coating can change mechanical tolerances, powder coated threads may not work or seat properly. If either the male or the female threads of an item have powder coating, you will need to remove the paint without damaging the threads.
Tape over any area of the part that you want to remain powder coated. Put on rubber gloves and eye protection.
Pour 1 tbsp of aircraft paint stripper into a glass bowl.
Dip a natural bristle artist's paintbrush into the aircraft paint stripper. Paint the threads, applying liberal amounts of the aircraft stripper.
Wait until the paint bubbles and has a gel-like consistency. Depending on the brand of aircraft paint stripper you use and the thickness of the powder coating, this time can vary. If the aircraft paint stripper absorbs into the paint and dries before reaching a gel-like consistency, reapply the aircraft paint stripper to the threads.
Use a paper towel to wipe the powder coating from the threads. Use a stiff wire brush to clean any powder coating residue from the threads. Reapply the aircraft paint stripper to remove any remaining powder coating.
Wash the item with a wax and grease remover to remove all traces of aircraft paint stripper. Rinse the item with clean water and dry with a rag.
You can also use an aerosol gasket cleaner to remove powder coating. It is harder to apply the aerosol to small areas and specific spots without getting overspray onto other powder coated areas, however.