This study presents an investigation for the development of tool life models during heat assisted machining and conventional dry end milling of AISI 316L stainless steel. The models have been developed and compared in order to evaluate the influence of external heat in machinability improvement of AISI 316L stainless steel using uncoated WC-Co insert. Three (3) level factorial design was utilized in establishing the tool life models in terms of cutting speed and feed as independent cutting parameters. All of the machining tests have been conducted within particular range of parameters using 100 cutter immersion. Tool life and response contours of metal removal have been investigated. Analysis of variance (ANOVA) was used to determine the most significant factors affecting the tool life. The results show that cutting speed is the main influencing factor on the tool life of uncoated WC-Co insert during cutting at both elevated temperature condition or while conventional machining at room temperature of AISI 316L stainless steel. This is followed by the feed and the machining temperature in the same order. © 2006-2016 Asian Research Publishing Network (ARPN).