The mass of charges included exporting, possessing and distributing objectionable publications, abduction for sex, unlawful sexual connection and sexual conduct with children - aged 3 to 6 - as well as minor drug-related charges.
The offences occurred in Tauranga from 2016 and Kerikeri from 2017 to 2019 in the homes of the five victims or at Ruddell's house.
The youngsters were the children of women befriended by the father-of-two, socially and at work.
Customs forensics specialists found 1191 child sexual exploitation images and videos on Ruddell's seized Samsung mobile and HP laptop.
Among the seized footage were photos and videos in which Ruddell had captured evidence of his own offending.
Inside the Whangārei High Court, emotional victim impact statements were heard from the mothers and a grandmother of the abused girls.
"I'm here to be our children's voice - the voice you stole," one mother said as a tearful Ruddell kept his head cradled in his hands.
A grandmother faced Ruddell and told him of the heartache and grief her family experienced when he "shattered" the innocence of her granddaughter. She said her own daughter was "lost" after turning to drugs to cope with guilt at being unable to protect her own young child from the "calculated predator".
"You were an imposter portraying yourself as a loving family man and father ... to get closer to her and gain access to her child," the grandmother said.
Her daughter left her 4-year-old with Ruddell, who was considered a close friend, while she attended a job interview as a "step to a better future".
Ruddell blindfolded the child and tied her arms behind her back while he sexually abused her.
"I trusted you and you violated her physically and mentally with acts of cruelty and depravity that can never be undone."
She said from that day her granddaughter displayed anger the family had never before seen.
Another mother described how the "calculated predator" became her "best friend" and in doing so gained the trust of herself and her 2-year-old daughter.
"My daughter wrapped her little arms around your legs, looked up to you and said she loved you. I replay this day over and over, every day," she said.
The mother said she stepped out of her comfort zone when she let Ruddell take her daughter to McDonald's on a playdate with his own son to get "icecream and play at the park".
Two hours later Ruddell dropped the child home, and she ran straight to her mother crying.
"Two hours in your hands and three years of suffering."
The woman said when the police investigation and court case unfolded, her daughter cried for Ruddell's son and his baby brother, who were "going to lose their dad".
In a short letter written to Justice Woolford and read out to the court by defence lawyer Doug Blaikie, Ruddell said he hated himself and was "truly sorry" to his victims and their families.
"I hope they will be okay ... and live to have happy and fulfilling lives," the letter said.
Ruddell's sentencing follows a Customs investigation when it detected someone from New Zealand uploading child sexual exploitation images to a popular social media platform. The upload was linked to Ruddell's home address, He was arrested and electronic equipment seized in November 2019.
• If you have concerns or suspicions about an individual who may be trading in or producing child sexual abuse images or videos, call Crimestoppers anonymously on 0800 555 111. If you are, or know of, someone who is at risk or being sexually abused, contact Police immediately.
Where to get help:
• If it's an emergency and you feel that you or someone else is at risk, call 111
• If you've ever experienced sexual assault or abuse and need to talk to someone call the confidential crisis helpline
Safe to Talk
on: 0800 044 334 or text 4334
• Alternatively contact your local police station
• If you have been abused, remember it's not your fault
