Building Model Boats Using Household Rubbish


Building Model Boats Using Household Rubbish
By Gavin Atkin

For each of the past three years my children and I have entered a competition at my local sailing club to build a model sailing boat from rubbish. It's an idea I'd suggest for almost any kind of boat enthusiast's event, so long as it goes on long enough to build the boat! How about it you messabouters? Making model sailing boats from rubbish can be fun for both kids and grownups, it's a good learning exercise, and you don't need a competition to make it fun.

At our sailing club the boats are generally the result of some kind of collaboration between kids and their parents, and our family's models certainly fit the pattern. My children, nine-year-old Ewan and seven-year old Ella have all sorts of views about the items we should use and how they should fit together, but also insist that I think of ways of making the boat they want use to work.

I'm glad to say that each one has worked, but also that we've learned something new each year.

The first year

The first time we entered, I tracked down some square-section guttering, cut two sections and sandwiched a piece of waste ply between them. I then used gaffer tape to make a double-ended bows and stern, and with odd bits of dowel, drinking straws and plastic carrier bags made a carefully calculated rig - the masts slipped neatly into holes created by slots I'd cut into the sandwiched ply before assembly. We also gaffer-taped taped fishing weights onto the bottom of the ply keel to give the boat some righting moment in reasonably streamlined underwater package.

The kids were delighted. The boat looked impressive at about two and a half feet long, and had two masts with equal sized white plastic bag sails. Initial trials had it sailing upwind remarkably well with its long keel and good sail area it would have stayed on the wind all day. I was particularly pleased with this, for I had carefully calculated the centre of effort of the rig and placed it exactly over the centre of lateral resistance of the hull, and my calculations had obviously been correct.

But our boat didn't win. It would only sail hard on the wind, and that we found is not what is wanted from a model sailing boat - it's too dull. A model boat is obviously nothing like so fast on the wind as it is on a reach. It doesn't do anything fun in the gusts. What's more, you can't easily make it sail across to the other side of a pond, run round and send it back to where it came from.

After the judging was over, I savagely slashed the mainsail to about half its original size with a handy pair of garden shears and launched it again - and this time it flew off like a rocket. It was fast, it was directionally stable, it was fun and Iím pretty sure that set up like this it could have won the competition.

Although we'd lost, we did learn something useful about the balance of free-sailing model boats, and we also had a good design, even if we did not feel able to use it again. I'm only sorry I haven't got a photo to show you.

The next year

The following year we completely forgot to bring any rubbish with us, so were obliged to buy some. It wasn't difficult: in a village corner shop we bought two completely useless hollow plastic baseball bats (they would have bent on hitting a softball and were entirely useless, except as rubbish), some string and tape, a bottle of mineral water and some garden canes. The bats made the hulls of a catamaran, and the cane made cross members, an aft sloping mast attached to the fore cross member and two further bits of cane supported the mast from aft corners of the catamaran.

We drank the water and cut the sides of the bottle into two strips, which we folded over the bats and taped to make small keel-lets that could be moved up and down along the length of the bats to control the balance of the hull and rig. Once the keel-lets had been adjusted for a reach, this weird looking entry (see picture above) nevertheless sailed acceptably well. I like to think that it was a worthy contender, even if it didnít win, and I'd suggest rubbish boat builders might consider trying something like it, not least because itís so quick and easy to make, and allows the adjustment these boats need. The downsides are that they don't look much like sailing boats and they have too much windage to make a good upwind sailers - but as our first year's entry showed that doesn't matter.

This year

This year, however, we did a lot better in the contest - in fact, we won. The latest entry benefited from a little planning (this time we brought some rubbish and some glue and tape!) and the kids, being a little older, had more of an idea of what they wanted. It had to be a catamaran made from four PET drinks bottles glued end to end. Scrap bits of ply made cross members, and the mast (that cane again!) was held up with some fluorescent pink builder's string. A single Bermudan sail flew from the mast, and an off-centre keel slotted onto a central cross-member, while a fixed 'rudder' was stuck to the aft end of one of the hulls. The whole thing was balanced by eye to sail on a reach, and initial tests revealed that the model again sailed well and needed no adjustment. We fixed a slight tendency to pitch pole by putting a little water in each of the aft-most bottles and off she went on a reach while most of the rest of the entries scuttled off downwind. (see picture below)

Next year?

I really don't know what will happen next year. Perhaps they'll prevent us from entering. If they don't, we may have to scratch our heads a lot harder to think of a low tech easy and quick rubbish sailing boat project. Now, does anyone remember reading a series of web pages about those model sailing boats they race somewhere in Polynesia?