For the National School of Opera in 1963, Sandford took part along with Janet Baker, Jennifer Vyvyan, Marie Collier and others, in a gala at Sadler's Wells Theatre. "The Times" praised his "distinguished singing" and added, "we hope this talented singing actor will not remain forever in Savoy opera." Sandford had been invited to join the company of the Glyndebourne Festival in 1961, but with a young family to support he felt he could not abandon the security offered by his D'Oyly Carte contract, and thereafter "it was never the right time or the right financial deal to lure him." Sandford sometimes bridled at the D'Oyly Carte directorial "traditions". He was originally trained in his roles by Eleanor Evans (Mrs. Darrell Fancourt), then the company's stage director. Sandford later recalled,