The rim must be stamped in just the right curving shape so it will curl slightly inward once it has been welded to the gong. This shape gives the gong extra resonance and enables it to sustain a note for a longer time.
鑼邊要剪裁成扇形，焊接到鑼面之後才會呈現向內包的斜度，使得銅鑼的共鳴度更好，聲音可以拉得更長。