Masking Caps

When a manufactured part is coated there may be certain areas of the surface that must be free of coating. For example, threaded areas may not fit properly if they are coated. Bearing surfaces with close tolerance cannot be coated. Some parts may require a bare spot for electrical-grounding contact. It is important to select a mask that is effective, easy to use and reasonable in cost. Masking may be done by caps, plugs, tapes, stoppers etc.
Masking parts will add additional labor to the coating process. It is important to understand the different types of masking products that can be used. Masking can be as simple as placing a plug in a single hole or it may require a specially made mask or fixture. One large hole in a large part will require very little labor while some smaller parts may have numerous spots that need masking and require a lot of labor. Selection of the right masking procedure will affect the cost of the part. The mask must be reasonable in cost and it must do an effective job of keeping the coating off the masked surface.