The critical piece of this assembly is an Aluminum Pizza Pan. The pizza pan needs to be a minimum diameter of eighteen (18) inches, although we recommend twenty (20) inches. You may need to go to a restaurant supply store to find a twenty inch pan. The aluminum finish makes it extremely difficult, if not impossible, for squirrels to grip the surface. A hole needs to be punched in the center large enough to slide onto the shepherd's hook. We simply punched a hole in ours with a large standard screwdriver and hammer.
To hold the pizza pan in place on the shepherd's hook, we use a large three inch Bull Dog Clip. The pizza pan needs to be high enough off the ground to be above squirrel jumping distance. We've found that to be about four and one-half feet.
To ensure that the feeder is in fact squirrel proof, it must be located beyond the horizontal jumping ability of any living squirrel. We have found that placing the shepherd's hook at least six feet from any tree, power line, or roof seems to do the trick.
Once assembled, you will enjoy hours of entertainment watching squirrels attempt to scale the shepherd's hook. Eventually, however, they will give up.
If you want to feed the squirrels, well that's your choice. We prefer to focus on the birds. The squirrels sit under the feeder and feast on the debris.