Cross two 2 x 4s at a right angle, cut a groove down the length of one to hold the keel, fasten wheels to the ends of the other with lag bolts, and there you have it: a canoe carrier.
I have paddled my canoe along streams, motored it up rivers, and even sailed it across lakes. But when I lift it now, it seems to have grown heavier than when I bought it in 1976! So, I decided it would be easier to move it to water on wheels.
What I wanted was a simple, cheap, and compact canoe carrier. If stowable, I might even take it along for use on portages that have wide footpaths. Here’s how to build what I came up with.
First, measure your canoe at its widest, the center, so the crossbeam of the carrier won’t be too short to fit outside the canoe. (Add an inch or two just in case your steel tape measure has shrunk or maybe your assistant is a poor carpenter.) Saw that length off the single 2-by-4 board you will use.
To mount the wheels, drill small pilot holes squarely in the center of both ends of the board you have just cut, to accept lag bolts that will fit through the wheel hubs. Don’t screw them in too tightly because the wheels need to turn. The rest of the 2-by-4 should be sawed about 2 inches shorter than the crosspiece.
Now measure the width and depth of the canoe keel strip so you can cut a groove into the shorter piece to accommodate it. I set my skill saw width-cut gauge just past the center of the 2-by-4 width and ran it down both sides of the board center line, leaving a cut about three-eighths of an inch wide. The depth of my canoe keel was a half inch, so I set the blade depth just over that. This groove prevents the wheels from twisting out from under the canoe.
Center the keel piece on the crossbeam at 90 degrees, clamp it and drill two holes, the diameter of your pair of 3 1/2-inch-long bolts, through both boards. I used three-eighths-inch bolts. Drill larger holes for the heads of the bolts with a countersink or larger bit. Bolt the pieces together. Wing nuts or bolt knobs will eliminate the need for a wrench.
Screw strong eyebolts just inside the wheels at each end of the crosspiece for a tie-down strap. Center the canoe on the keel piece and tighten your tie-down. Grab the front and you are away.
It works well enough across grass, dirt or packed sand. If you’re planning to pull it over soft sand or rough terrain, perhaps you could use pneumatic wheelbarrow wheels.
With a few minor adaptations, this plan also could be used on smaller-sized roof-top boats.
When you have arrived at the water, loosen the bolts, line the keel board across the centerboard and tighten the knobs for storage.
I have no idea what results you would get if you left the wheels on while paddling.