The following release was originally posted on Sailing Scuttlebutt: Getting techie to build the plug

Published on December 5th, 2020

With the anticipated launch of the new J/9 in Spring 2021, J/Boats describe the process to commence production:


J/9 hull and deck plug construction has been completed by Symmetrix Composite Tooling in Bristol, Rhode Island. Symmetrix is the most advanced precision tooling company in New England and carved both the J/9 hull and deck plugs using the state-of-the-art CMS Poseidon 5-axis Machining System.

This machine has an overhead computer-controlled universal robotic cutter head that runs down calibrated tracks on top of the walls from one end to the other and can reach almost anywhere within the space.

Symmetrix engineers analyzed the J/9 3D design models provided by J/Boats using the Siemens NX11 CAD/CAM software and ran a series of simulations to arrive at final machining instructions for the 5-axis milling machine. The Siemens NX11 software is a quantum leap forward in delivering tooling not just quickly, but also accurately.

The same machine is used at leading edge, high-tech aerospace companies like Boeing, SpaceX, and McDonnell Douglas. The NX10 gives Symmetrix complete surface model control and simulation in full 5-axis machining instructions; it can achieve tolerance within 1 millimeter over a 26-meter surface and in a fraction of the time.

Then, the exciting part starts. First, the steel backbone frame with foam blocking is milled to within an inch or two of the final plug surfaces (all milled foam is recycled). Then, the plug and foam are encased by fiberglass/epoxy reinforcement. Finally, an epoxy milling paste is applied over the glass.

The part returns to the milling machine for a second and final precision machining operation to take it to the final surface. Hand-sanding to 800 grit and buffing to a mirror shine then completes the effort.

From initial steel framing construction, to precision milling operations, to the final polishing, the process to build a complete mirror finish hull/ deck plug took just seven weeks. Production molds are under construction at CCF Composites and thereafter the J/9 production begins after January 2021.