river jet boats
About //
WattsCraft
WattsCraft is a small company based in Otago, New Zealand. We design & sell jet boat hull kit-sets. We also have tools and knowledge to design custom aluminium boat hulls.
WattsCraft use modern design tools & processes. We outsource certain fabrication processes such as CNC cutting as required to a range of specialist companies, this gives us the flexibility to use the best process for the job.
- CAD Design
- Welding – TIG, MIG, ARC (All materials)
- CNC router cutting
- Forming – Press brake, rolling, tube bending
About //
WattsCraft
WattsCraft is a small company based in Otago, New Zealand. We design & sell jet boat hull kit-sets. We also have tools and knowledge to design custom aluminium boat hulls.
WattsCraft use modern design tools & processes. We outsource certain fabrication processes such as CNC cutting as required to a range of specialist companies, this gives us the flexibility to use the best process for the job.
- CAD Design
- Welding – TIG, MIG, ARC (All materials)
- CNC cutting – Router, laser, water-jet, turret punch, etc
- Forming – Press brake, rolling, tube bending
- CNC machining/milling
About // WattsCraft
WattsCraft Boat Design
WattsCraft specialises in designing high performance river jet boats. We pay careful attention to several attributes which are particularity important in small boats.
Good weight distribution is essential to ensure performance & increase stability when running aground. Assuming all other factors remain the same, as a boat becomes narrower its static stability is reduced. WattsCraft designs “add” stability by:
Using a shallow dead-rise and reverse chines allows the chines to be closer to the ground. This makes the boat harder to roll over.
Mounting heavy items low & at the rear of the boat. This keeps the centre of gravity as low as possible. It also helps to keep the boat tracking straight when running aground. Excessive weight in the front of the boat can cause plowing & bow-steer in water & on gravel.
Using low seating near the centre (longitudinal) of the boat. As passengers are a large proportion of the total weight having low seats is much more important to stability in smaller boats. It also helps when ducking willow branches. Avoiding having seating too far forward is also important to avoid excessive weight in the front.
Hull design. Small boats typically carry more weight further forward. We use a constant dead-rise design to provide lift in the bow area & ensure a flat stable ride at high speed.
Having positive predictable handling in a river full of obstacles is important and a small nimble boat is a big advantage in your typical NZ river. WattsCraft have a few priorities when it comes to handling.
No unexpected spins. We design our hulls to avoid bow steer (oversteering). Our constant shallow dead-rise aft section resists porpoising, tracks straight and gives predictable cornering. A moderate bow entry allows for positive steering with standard jetski deflector nozzles & cuts through little chop with a dry ride.
The constant dead-rise hull sits flat as speed increases & never rides bow down. Cornering remains constant & inspires confidence at any speed.
Construction
WattsCraft hulls are CAD designed, CNC router cut and CNC folded. 5083 grade marine aluminium plate is used throughout.
The hull is reinforced by folded plate longitudinal stringers. The topsides are a strong monocoque structure with large folded box gunnels which require no framing for strength. The windscreen is strong & high enough to hide behind should a tree branch drop unannounced into your path.
Components
We use cable & pulley steering from SSS. This is typically found on full sized jet boats & marathon race boats! We dont recommend push-pull cable steering.
We also recommend and retail SSS reverse & trim controls.
We retail ASPCNC cast intakes & river grills. These are by far the easiest most advanced intake/grill system available for adapting jetski pumps into jet boats.
Henry Wadworth-Watts
Academic:
- ME (Environmental engineering)
- BE(hons) Chemical & Process Enginnering
Experience:
- Boat & industrial design
- Architectural metalwork
- Environmental engineering
- Chemical & Process engineering