Much larger vessels, yachts for example, require a different approach. In these instances, it is desirable to print the mould itself rather than print a plug or pattern from which a mould is made.
Working with an undisclosed marine industry collaborator, Thermwood has printed a scale model of such a hull mould to test and validate the process.
The 1/7th scale test mould for this project is approximately 7ft long (the full-size hull is approximately 50ft). It was printed from 20% carbon fibre filled ABS using Thermwood’s LSAM additive manufacturing machine.
Six separate pieces of different lengths, the longest two, each being over 7ft long, were printed concurrently using LSAM’s Vertical Layer Print capability. Printing required about 30 1/2 hours.
The ability to simultaneously print multiple parts of variable heights highlights the flexibility of both the vertical print process as well as Thermwood’s LSAM Print3D slicing software. The parts were then trimmed on the same machine and assembled into two mould halves.
The tool includes a deep undercut at the transom, so the finished mould needs to be two pieces, split down the middle. These mould halves are clamped together for layup and then separated to remove the finished hull after curing.
Moulds for hulls of longer than 50ft will be printed in multiple sections, assembled for hull layup and then disassembled to remove the finished part. The test tool printed here simulates that assembly and disassembly process.
The tool printed in this program will be tested using production materials in a production environment. Thermwood continues to work on methods and techniques needed to refine this into a production ready process.
Thermwood believes that the marine industry will benefit significantly from emerging large-scale additive manufacturing technology and that this project is a significant first step toward the direct production of large vessel tooling.
