The four were among 24 trainees under the guidance of the same number of professional crew.
They worked all day, every day.
"We had a different shifts, sometimes it was midnight to 4am, or 12am to 4pm in afternoon, but in the meantime we had to assist on weighing the anchor and assist the crew taking down some sheets.
"On one day we could be out there three times for two to four hours."
Work including weighing the anchor, working the sails, teetering 40m in the air on a harness, washing the deck, steering and guiding the boat at the helm. Trainees also had to clean below deck.
The Australian-built replica of James Cook's HMB Endeavour is true to the original.
It includes a maindeck and an 18th century deck where guests slept in hammocks.
"We had a couple of really bad days with four to five metre swells and you were trying to sleep you'd be swaying in your hammock.
"It was somewhat intense."
Frank says the experience was "epic".
"It was the experience of a lifetime. I'm glad I had the opportunity."
One surprising thing was the quality of the food. James Cook and his crew probably didn't have the luxury of two cooks in the galley.
"I was expecting to have to open a can of beans for dinner but the meals were top notch. It was all homecooked meals, which was some extra comfort for us."
ABOUT THE ENDEAVOUR REPLICA
● The Australian-built replica of James Cook's HMB Endeavour is one of the world's most accurate maritime replica vessels, opening a window on a sailor's life during Cook's 1768-71 world voyage. The replica carries almost 30km of rigging and 750 wooden blocks or pulleys. The masts and spars carry 28 sails that spread about 930sq m of canvas.
● Construction of the Endeavour replica began in 1988 and the ship was launched five years later. Since then, she has sailed more than 170,000 nautical miles (twice around the world), visited 29 countries and many Pacific islands, and opened as a museum in 116 ports. Hundreds of thousands of visitors have come on board to see how Cook and his men lived.
● The Endeavour replica has visited New Zealand in the past, with the most extensive visit being an 11-port tour in summer 1995-96. Most recently the ship visited New Zealand on the return leg of a second world voyage, this was in March 2005. The ship has not been to New Zealand since ownership of the vessel moved from the HM Bark Endeavour Foundation to the Australian National Maritime Museum in April 2005.