Plastic ABS drain pipe can be used to make a cheap, tough, light weight canoe cart. I have built several over the years and given them a good thrashing without the plastic failing. The current recommended model is below.
2″ ABS plastic pipe
5/8″ aluminum axle
16″ overall diam. x 4″ pneumatic tires
Weight approx 18 lbs with steel wheels.
Plastic wheels would save a few lbs.
In general, keep your carts low and wide to avoid the canoe flipping over and dumping it’s contents on the trail. Bowron Lakes Provincial Park here in BC limits cart widths to max 30″. This width works well on the portages. Cart height; you want the cart to be high enough so the trailing end is not bopping roots and rocks on the portage while you haul your boat along, but low enough so it doesn’t flip on an incline. Aim for about 17″ total height (not including the foam.) The cart to the left is a bit high, a result of me putting much larger wheelbarrow wheels on the cart. These carts will take a considerable load over a rough trail without breaking, so I feel they should be suitable for dragging small sailboats around a marina.
The cart to the right is an older model made of 1.5″ ABS pipe. It has held up without problems. The wheels are off a jogging stroller with pneumatic tires and plastic spokes. It weighs eleven lbs. This cart has been grossly overloaded with the wheels visibly flexing on impacts with trail hazards. The cart is still in great shape but I felt the frame could be simplified (it has 10 ABS fittings to the current 4) and the wheels should be beefed up.
The cart to the left was built for my Wee Lassie mini canoe but was pressed into service hauling a fully loaded 16ft canoe with a weeks supplies. I was curious how it would hold up. About a mile into the first portage the aluminum 3/8″ axle bent, but kept on going. If you must use 3/8″ diam. axle use heavier stainless steel, unless it is only for a light load. 5/8″ aluminum is better.
Aluminum comes in different alloys, varying widely in strength, corrosion resistance, price, etc. It makes a difference. Aluminum can be color coded to indicate what alloy it is made of. Both of the rods at the right were sold as 6061 to your uninformed writer. Aluminum color charts here: westlakemetals.com and trident-metals.com
It helps to position your cart a little toward the stern of your boat, with the load balanced over the wheels. This way when you are pulling your boat over terrain there is greater clearance for the stern over rocks and roots on the path.
Use nylon webbing and plastic buckles to tie your boat to your cart, it is far more convenient than rope. 1″ webbing will do.
More coming soon, with some free plans.