He is a folk musician, and has made several recordings with Brenda Wootton, as well as a poet in writer in Cornish itself under the bardic name of "Gelvinak".
Gendall founded Teere ha Tavaz, an organisation which seeks to promote the Cornish language in its Modern Cornish or Curnoack Nowedga variety. It is also a small publisher on, and in, the Cornish language.
^Observer online - Sunday 31 July 2005: "How do you say 'bugger off' in Cornish?" by Jonathan Sale: "And he [Gendall] ought to know, having started learning the language in 1928 at the age of four and is now a linguistically vigorous 81."