The 3M self adhesive foam mounting tape on these HCI-LED modules is excellent. In fact, when commercial sign companies use these modules to backlight outdoor channel letters and other signage, they don’t use screws but trust the 3M adhesive to hold the modules in place permanently, and that’s across wide temperature swings. Of course, those are ideal painted-metal surfaces, so while indoor applications aren’t so demanding, not all surfaces are so ideal. So, if you think you may have trouble with a surface, first of all, it is always best to assure surfaces are free from dust and oils for best adhesion. Then if you’re really concerned, you could prepare and stick your first module in place and let the rest of the string hang from it for hours or a day to make sure it will hold before installing the rest. If you do encounter surfaces that don’t give a good bond, such as rough wood surfaces, try this:
Besides cleaning as mentioned above, we have found that contact cement works well for these tough surfaces. Coat the target surface and the back of the LED module, allow both to dry as recommended (about 15 minutes typically), then carefully position and apply (because you can’t really reposition after the surfaces touch).
Also, our LED modules have at least one 3/32″ hole allowing for use of a #2 screw to assist securing the module. You can try your local hardware store for 1/2″ long #2 wood screws, but they can be tough to find locally so we try to keep them available in our online store.