Think green, save anti-fouling, The new-design Boat Bag
by Kate McCallum on 17 May 2010
Adams10 in BoatSaver boat bag 01 Henri Desmarais
'I haven’t anti-fouled my boat in years,' says Martin Ross.
Yet Ross, an experienced year-round yachtsman, is like most boat owners and wants to keep his boat clean. 'For me, keeping the hull clean is paramount.
'I was having to antifoul, then pay for a diver every few weeks to scrub the hull.'
That all changed, he says, when he started mooring his boat in a new-design Boat Bag.
So what exactly is a Boat Bag and how does it work?
A boat bag is a floating pvc liner, designed to sit under a power or sail boat either on a swing mooring or in a marina berth. The bag works to stop the tidal flow so organisms are unable to come into contact with the boat. The aim of the bag is to minimise growth and keep the boat’s hull and underwater propellers clean.
The concept is not new, though the designs have been significantly improved.
'Bags for sailing boats have been around for nearly 20 years', says Tony Clark, Managing Director of Boatsaver Boat Bags which commenced manufacturing boat bags in 2009. 'However, the old designs were often difficult to get in and out of, there were quality issues that caused the bag to disintegrate prematurely, and they were not customised – a particular issue for power boats.'
According to Ross, the new designs are a significant improvement on old efforts. 'Tony and the team at Boatsaver have greatly improved the design. They asked fellow sailors who’ve used the old bags what we thought and took on board our modification suggestions to overcome the shortcomings of the originals. So, with the new product, what you’ve got is the result of many experienced yachties working together to develop a bag that does the job and lasts.'
So what is so innovative about this product?
'We’ve made key design improvements for both sail and power boat owners that make the bags easier to use and longer lasting', says Clark.
In fact, this looks like the first time this type of bag has been specifically designed for power boats. According to Clark the biggest complaint from power boat owners is that they want a shallow u-shaped bag, that more closely follows the shape of their boat.
'This is particularly useful for shallow mooring locations where the traditional deep v-shaped bag caused problems.' According to Clark, the v-shape bag can easily get caught in the mud in shallow waters and so can’t swing with the tide and wind. Not only does this annoy neighbouring boat owners, it also makes it very difficult to enter and exit the bag.
This is a one of the major concerns that Boatsaver’s Clark says that his bags have resolved. 'We’ve designed bags for both power and sail boat owners that will remain open so that’s its effortless to enter and exit.'
'We’ve worked out one of the main secrets to easy access – it’s all to do with the relationship between the water in and out of the bag. With the old closed bag designs, when the boat was out, the sides of the bag would close up and very little water remained inside. As you can imagine, there was a lot of pressure from the water outside but virtually no counter force from the inside. So, as you tried to open the rear of the bag the plastic would suck in and made it very difficult to open. What we’ve done differently is to shape the sides of the bag with pvc piping – this helps ensure there is a substantial volume of water in the bag even when there is no boat in it. We also have a design where the bag remains open.'
Another advantage of the new boat bag design is that it is less subject to twisting or stretching. This means the bag is less impacted by stress caused by tidal movements and owners can expect a longer life from their bag.
Another life-extending feature is that the new bags do not need to be tied to the boat. 'This is a real issue with the old bags. Having to tie the bag to the boat puts the fabric under unnatural strain – you want your boat to be able to move freely up and down with the wave motion, and your bag to remain stable in the water. We’ve seen cases with old designs where stainless steel bolts on the boat have been stretched and snapped, or rudder posts have been bent.'
Boatsaver has worked out how to construct a bag so that the boat and bag can move independently of one another reducing damage to the boat and extending the life of the bag.
Professional design and manufacture:
There are a team of experts behind the scenes involved in the design and manufacture of Boatsavers’ boat bags.
'We’ve consulted with industrial designers, pvc specialists and industrial chemists. We selected experts in the plastics industry to manufacture the bags. And in the design phase, we’ve used people with 20-plus years of experience in CAD design to ensure each bag is suited to the underwater profile of the boat.'
Boatsaver also keeps up with the latest materials to withstand UV and fatigue for a longer lasting bag. 'We use high quality PVC that has 3-year manufacturer’s warranty', says Clark.
It’s not just design and manufacturing experts who’ve helped make the new bags successful. Clark was thrilled to tap into the experience of existing boat bag users, like Ross. 'These guys have used and perfected the design over more than five years – what better way to understand the old bag’s limitations and identify in real conditions what works and what doesn’t', says Clark.
From Ross’s perspective, this test of time is important. 'We’ve tested all sorts of ideas on our bags over the years. Designed well, we know they are easy to use, we know they will keep the boat in top condition, and we know we don’t need anti foul – I haven’t anti fouled in five years.'
Good investment:
Ross regards boat bags as a good investment too. 'I used to pay $1500-plus for antifouling, then $60 every few weeks for a diver to scrub the hull. If you use a bag correctly you can say goodbye to all that fuss and cost. The bag should pay for itself in less than 18 months - and the bigger the boat the bigger the savings.'
Clark believes that many people aren’t aware of the potential savings. 'From my conversations with boat owners, I would say that there is a real lack of awareness around how substantial the improvement is with a boat bag to the cleanliness of the hull and underwater propellers.'
'It’s revolutionary', says Clark. 'Our bag design is not just a better mousetrap. We’re not talking about finding an improved antifoul that sticks better, we’re not talking about how to more easily remove barnies. We’re instead focusing our efforts on where it matters most – prevention of annoying growth and a cure for a clean boat.
For more information about the company and its products, or to purchase from anywhere in the world, go to the www.boatbag.com.au!Boat_Bag website
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