Bi-metal band saw hniav npog qhov dav tshaj plaws ntawm kev siv sawing thiab cov khoom siv. Kuj tseem hu ua M42 / M51 cov hniav, cov no muab cov txiaj ntsig zoo, kev ua haujlwm siab, thiab lub neej qaug zog zoo heev. Qhov zoo tshaj plaws kev lag luam thiab thaj chaw pom hniav sib txuas ua ke ntawm lub caij nplooj ntoos hlav-steel backer nrog kev hnav tsis kam ntawm M42 / M51 high-speed steel hniav.