Fig. 8.
Fig. 9.
Temperature of the Metal.
It is essential that the temperature of the metal should be kept uniform. If the temperature is too high, porous or spongy slugs will result, also defective faces and a weak surface, which allows the letters to sink in printing.
A temperature that is too low causes the metal to adhere to the mouthpiece and prevents the free flow of the metal to the mold.