John Allen, 73, denied 40 counts of sex abuse against 19 boys and one girl in the late 1960s up to the early 1990s.
He was found guilty of seven sex charges at Mold Crown Court on Thursday. He was found guilty of 26 charges on Wednesday.
The jury were discharged after failing to reach verdicts on the other charges.
Allen, of Needham Market, Suffolk, will be sentenced on Monday and was warned he faces a life sentence.
Earlier on Thursday, Mr Justice Openshaw told jurors he was prepared to accept verdicts by a majority verdict and they later returned six by a majority.
The judge said there was no prospect of re-visiting the remaining charges after the jury had deliberated for more than week.
The case was the first prosecution following the Operation Pallial investigation into allegations of historical sexual abuse at children’s homes in north Wales.
One former resident at the Bryn Alyn children’s home said living at the establishment “wasn’t care, it was like hell”.
Ed Beltrami, chief crown prosecutor for CPS Wales, said Allen had been convicted of a “shameful catalogue of abuse”.
Article source: BBC News 27/11/14