Docking the John Oxley

The Sea Heritage Dock is a simple floating box like structure, much like a pontoon. It can be sunk and raised beneath ships to keep them out of the water for repairs and restoration. The Sydney Heritage Dock was built so that we could restore our larger vessels at our own site, at our own pace and using heritage techniques like riveting.

It cannot be sunk and raised like a floating dock. It is a slave dock. A large commercial graving dock is needed to interchange our large vessels. For example, when John Oxley replaced James Craig on the Sea Heritage Dock.

The steps below detail the process of using the Sydney Heritage Dock.

1	The Sydney Heritage Dock with the James Craig on top was docked in the Captain Cook graving dock at Garden Island, and all the water pumped out.
2	The flooding doors in Sydney Heritage Dock were opened. Water was then let back into the graving dock, the Sydney Heritage Dock stayed submerged; James Craig floated off and was towed away. Then, with James Craig out of the way the graving dock was sealed from the harbour.
3	The graving dock was pumped dry. The keel blocks on the Sydney Heritage Dock were changed to suit the underwater shape of John Oxley.
4	The water was let back in and John Oxley was positioned over the Sydney Heritage Dock. The graving dock was pumped dry and John Oxley settled down onto the keel blocks.
5	The flooding doors on Sydney Heritage Dock were bolted up and she was again a watertight box. Water was let back in, The Sydney Heritage Dock with John Oxley then floated and was towed back to our Rozelle Bay Sydney Heritage Shipyard.

John Oxley on the Sydney Heritage Dock, being towed back to Rozelle Workshop

The above operation is expensive – the cost to exchange James Craig with
John Oxley was more than $100 000. See Support.