Did my extrusion die get enough heat?
Preheating of a die is an essential factor of extrusion. When a die has had to little heat it could tear. Through different factors the temperature of the die could fall. On the basis of the color tabels below, it is possible to track down which temperature (circa) the die has had.
The extruder determines the temperature through knowledge and experience. Besides, some alloys provide the extruder to play with temperature during the extrusion process.
Annealing colour tables