Apart from 7-year-old Gary, the boys were all aged 8.
"I suppose, when you look back at it, there was a degree of recklessness that came with fireworks."
In the 60s, says Robert, no one blinked an eye at 8-year-olds buying pyrotechnics. Old Mr G Wah Lee, smiling in the background, had a stockpile in the weeks before November 5. The boys walked from Ponsonby to his store in the city. "You always knew where to get the bargain and he was definitely the best for that."
Guy Fawkes festivities were a big deal. Families gathered round bonfires on playing fields while fireworks lit the night sky. During the day, the boys asked for money to subsidise their Guys - effigies made of old clothes stuffed with straw and rags.
Decimal currency, introduced a year earlier, boosted the boys' income. "We'd normally ask for 5c, which was fairly optimistic. It used to be 'a penny for the Guy' ... but the price went up fivefold."
Robert has since lived in London, the US and Australia, but he still calls Auckland home - after all, he's been investigating its urban infrastructure for many years. "We used to get the Thunder Crackers. We'd light them and hold the cracker right over the drains ... and then you'd drop it into the drain just before it exploded. If you timed it right, it would explode in the water and all this water would erupt out the drain."