A method for producing a ceramic honeycomb body having large numbers of longitudinal cells partitioned by cell walls, with its peripheral portion removed by machining, includes rotatably holding the ceramic honeycomb body on a main axis of a lathe, and rotating the ceramic honeycomb body around the main axis, to remove its peripheral portion by machining with a tool; the lathe comprising a first fixing jig on the main axis, and a second fixing jig substantially opposing the first fixing jig; each of the first and second fixing jigs having an abutting end portion opposing each other, the abutting end portion having a smaller outer shape than that of the end surface of the ceramic honeycomb body, and the abutting portion having a substantially flat abutting end surface perpendicular to the main axis.

A method for producing a ceramic honeycomb body having large numbers of longitudinal cells partitioned by cell walls, with its peripheral portion removed by machining, includes rotatably holding the ceramic honeycomb body on a main axis of a lathe, and rotating the ceramic honeycomb body around the main axis, to remove its peripheral portion by machining with a tool; the lathe comprising a first fixing jig on the main axis, and a second fixing jig substantially opposing the first fixing jig; each of the first and second fixing jigs having an abutting end portion opposing each other, the abutting end portion having a smaller outer shape than that of the end surface of the ceramic honeycomb body, and the abutting portion having a substantially flat abutting end surface perpendicular to the main axis.

A method for producing a ceramic honeycomb structure comprising a ceramic honeycomb body having large numbers of longitudinal cells partitioned by porous cell walls having porosity of 50% or more, and a peripheral wall formed on a peripheral surface of the ceramic honeycomb body, comprising the steps of extruding moldable ceramic material to form a honeycomb-structured ceramic green body; machining a peripheral portion of the green body or a sintered body obtained from the green body to remove part of cell walls in the peripheral portion to obtain a ceramic honeycomb body having longitudinal grooves on a peripheral surface; applying colloidal metal oxide to a peripheral surface of the ceramic honeycomb body and drying it, and then applying a coating material comprising ceramic aggregate having an average particle size of 1 m or more to form the peripheral wall.

A method for producing a ceramic honeycomb structure comprising a ceramic honeycomb body having large numbers of longitudinal cells partitioned by porous cell walls having porosity of 50% or more, and a peripheral wall formed on a peripheral surface of the ceramic honeycomb body, comprising the steps of extruding moldable ceramic material to form a honeycomb-structured ceramic green body; machining a peripheral portion of the green body or a sintered body obtained from the green body to remove part of cell walls in the peripheral portion to obtain a ceramic honeycomb body having longitudinal grooves on a peripheral surface; applying colloidal metal oxide to a peripheral surface of the ceramic honeycomb body and drying it, and then applying a coating material comprising ceramic aggregate having an average particle size of 1 m or more to form the peripheral wall.