AMT Solid Carbide Thread Mills for Aluminium Machining. Carmex introduces a new line of solid carbide thread mills for High-speed aluminium machining. High-speed aluminium requires tools that minimize the tendency of Aluminium to stick to the tool cutting edges, provids high surface finish, ensuring efficient chip evacuation and sufficient strength of the cutting edge to absorb the cutting forces. Features: Optimized carbide grade for Aluminium, cast iron and Stainless steels. Cylindrical shank (Weldon shank upon request). With internal coolant bore. Uncoated, smooth cutting edge, High thread surface quality, Same tool for right hand or left hand internal threads. Additional items with cutting chamfer.