This study shows that the transition of metal transfer mode in gas metal arc welding occurs much more gradually than is generally believed BY Y-S. KIM AND T. W. EAGAR ABSTRACT. Droplet sizes produced in GMAW are predicted using both the static force balance theory and the pinch instability theory as a function of welding current, and the results are compared with experimental measurements. The causes for the deviation of predicted droplet size from measured size are discussed with suggestions for modification of the theories in order to more accurately model metal transfer in GMAW. The mechanism of repelled metal transfer is also discussed. The transition of metal transfer mode has been considered as a critical phenomenon which changes dramatically over a narrow range of welding current. This transition has been investigated experimentally using highspeed videography which shows that the transition is much more gradual than is generally believed. The mechanism of the transition is discussed using a modified static force balance theory.