When Emperor He came of age in 92 he led various officials, especially Zheng Zhong, in a coup d'état to overthrow the Dou family. Cai was not involved in their removal, and though Cai was previously allied with the family, he was undistributed by the Emperor's coup. In 97, his position expanded in scope, as he became responsible for ceremonial swords and other items. The describes his craftsmanship as that of especially high-quality and a model for later generations."In the 9th year of the era , he oversaw the manufacturing of imperial swords and other equipment, which were all made carefully and well, and he became an example for later generations.": "In the ninth year of the period (A.D. 97) Ts'ai Lun became inspector of public works. By his plans and according to his arrangements, engineers and workmen made, always with the best of materials, swords and arms of various sorts. Later generations could do no better than imitate his methods of work.": "In the ninth year of the reign of (A.D. 97), Ts'ai Lun was made inspector of works and through his efforts the engineers and workmen by the use of fine materials and skill produced swords and arms that served as models for future generations."</ref>