| An electrical connection as others have mentioned is needed. However, in the anodizing process, an electrical connection is needed as well, and most firms randomly put an electrode on the back side, such that the small spot where anodizing is missing will not be noticed. What you might do, is instruct the anodizing firm where to put this, or even suggest a zone where they should apply a masking agent in order to provide a conductive region to provide a ground connection.
Where shielding is really mission critical, we mask a continuous outline, and use electrically conductive gaskets... on the other hand, unless you are playing in proximity to a high powered transmitter, such would be overkill. For 50/60Hz and the resulting harmonics of such, a single point attachment to the pick guard should be fine. If you have electrical noise pickup from on stage motion controllers, then multiple point connections to the pick guard are likely in order. |