A trampoline has a trampoline frame that includes trampoline frame legs for supporting the trampoline frame, a trampoline bed extended across the trampoline frame for allowing users to rebound on the trampoline bed, a vertical frame member connected to a horizontal frame member, and a trampoline frame joint connecting the vertical frame member to the horizontal frame member. The trampoline frame joint has a joint sleeve formed as a strip. The joint sleeve is fitted to the trampoline frame joint. The horizontal frame member is connected to the trampoline frame joint. The joint sleeve overlies an opening rim edge of the horizontal member. The joint sleeve is welded to the horizontal member and the vertical member is connected to the trampoline frame joint. The vertical member is welded to the horizontal member.