To respond to requests for enlargement of a work and increase in cutting speed by providing a tip base for a milling cutter composed of a carbon material having a fitting part of a tip in its outer circumference.

A base 11 is formed of a carbon material substantially composed of carbon such as an isotropic graphite material. The isotropic graphite has heat conductivity 3-6 times as much as the stainless steel, suppresses expansion of a device by the heat generated in working, has less difference in its vertical/ lateral expansion rates because it is isotropic, and can secure a prescribed working accuracy. Because it is approximately 1/3-1/4 lighter compared with the metal, it is profitable for enlargement of a tool. In the contrast to the superior characteristic, it is weak in shock and apt to cause chipping and crack in installed in a device so that, after the tip 12 is fixed to a cutting 16 part for fixing the tip, a stainless steel protective metal ring 15 is shrinkage-fitted to the outer circumference to be attached to the device. These processes enable high-speed cutting.