HulFlo Boat Dryer

The Problem

HulFlo is a boat dryer to reduce the breakdown of structural materials in high-performance watercraft such as sailboats and rowing shells.

Keeping a boat dry helps maintain the performance of the boat and increases its life span up to 4x longer.

The HulFlo Dryer

The HulFlo System is designed to mount to a range of ports on a boat to circulate air and dry out the inside of the hull. This helps prevent rot, mildew, freezing damage, and delamination.

1-Way Plug Mount

The 1-way mount pushes air into the hull to exit out another port in the boat.

2-Way Plug Mount

The 2-way port pushes air into the hull through a tube and exhausts through the same port.

Inspection Port

The inspection port mount pushes air through a cap and exhausts through a tube or vice versa.

Product Beginnings

In 2014, a peanut butter jar combined with a solar motor was used to create the first prototype to dry out 29er skiffs while I was competing on the high-performance race team at the Kingston Yacht Club.

In 2018, the project was revisited and refined with the foam models below. At that time I also drafted a patent application for some of the features of the product.

Design Patent

2022 – The design was refined again and modelled with Autodesk Alias.

At this time an Industrial Design was filed with the WIPO* and the product was launched and branded as HulFlo boat dryers.

An Industrial Design protects the form of a product.

Registration Number: DM/224171

*World Intellectual Property Organization

Mould Making

Mould Plug Development

The original intent was to 3D print plugs to produce fibreglass moulds.

The Challenge

Warping of 3D prints made parting lines of assembled parts inconsistent.

Modified 3D Printer to Mill

To skip 3D printed plugs, an Anet A8 3D printer was converted into a mill using stock parts from the 5-axis CNC build.

To interface the machine with its original firmware with Fusion CAM processors, NotePad++ was used to modify the G-code.

*Computer Numerical System


The first mounds were made using foam and fibreglass. Some of the processes were adapted according to available materials due to Covid-19 supply line conditions.

Fairing was then used to produce a surface that was easy to machine and polish.

Inertial Forces

To finish the moulds after fiberglassing, they were mounted back on the mill.


The mill was made using a 3D printer with a linear Y-axis build table. During the calibration of the axis, the machine uses rapid movements. With the added mass of the fiberglassed part, it alters the Y-axis reference.

Wood Mould Making

To avoid issues of calibration, the mill was reinforced and wood was used for subsequent moulds. This allowed a mould to be produced in a single session on the machine instead of two.

Current Status

Over the course of the winter, I am working on re-tooling by getting the 5-axis CNC online. You can find that project in the list below.

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