Masking
Masking turns up in 2 fields: thermal spray, powder coating. Here is what it means to the people in each one.
Masking in thermal spray
Covering areas of a part that must not be blasted or coated, using tapes, plugs, shields or maskants.
Protection of surfaces that must stay uncoated, such as bores, threads, seal grooves and datums. Blast masking uses tough rubber or vinyl tapes and plugs to resist abrasive, while spray masking uses heat-resistant aluminum foil and glass-cloth tapes, silicone plugs, liquid maskants and reusable metal shields. Masking often takes more labor than the spraying itself, and poor masking is a leading cause of rework.
"Masking on the blade roots takes longer than the spray, so book the hours for two people."
Masking in powder coating
Protecting threads, holes and contact surfaces from powder with heat-resistant tape, caps and plugs.
Parts often need bare metal at threads, bearing bores, ground lugs and mating faces. Masking uses polyester or polyimide tape rated for oven temperatures, silicone caps and plugs, and custom die-cut shapes. It is removed after cure while the part is warm so the film breaks cleanly at the edge. Masking labor is a major cost driver and is quoted per feature.
"Customer wants bare metal in all eight bolt holes and the ground stud, put masking on the traveler."