Martin James Jegou, who changed his surname by deed poll from Richardson after his arrest in 2015, was found guilty of eight counts of indecent assault, two counts of procuring an act of gross indecency and one count of rape.
All of the offences were alleged to have involved one girl known as Miss X except for one count of indecent assault against a girl known as Miss Y.
The jury of three women and eight men took just over five hours to make their unanimous decision. The defendant was originally accused of three counts of rape but the jury cleared him of two of the charges and found him guilty of indecent assault instead.
Jegou was remanded in custody and is due to be sentenced in December.
