Customers often call or email us for instructions on how to pack their banjos for shipping. The way I ship all my new banjos and repairs out is as follows:
I put the banjo in its case and wad up a double sheet of newspaper under the peghead. I twist up a double sheet of newspaper and stuff it around each side of the pot (to prevent thumb screws from vibrating out of the resonator). Just before shutting the case I wad up a double sheet of newspaper over the peghead to prevent whiplash. I close the case and prepare a box with a padding of wadded up kraft paper (50 pound) on the bottom to cushion the pot end of the banjo case. I stuff the case down into the box crushing the kraft paper. I stuff more kraft paper around each side of the case to immobilize the case inside the box. Lastly, I stuff a wad of kraft paper over the end of the banjo case and close the box up.
Any packaging medium will do so long as the banjo in its case is immobilized inside the shipping box and there is some space between the inside of the box and the outside of the case.