A Kayak Cart

(Article by Mark) As time passes and I get older, the thought of carrying my kayak long distances to or from the water becomes less and less appealing. I have a commercial cart I use to haul kayaks up and down our hill, but it doesn't fit conveniently in a boat. My goal was to come up with a simple cart that would work well on fairly hard surfaces and that would fit into both the front and rear hatches of my boat. It had to be easy to take on and off, and preferably inexpensive.
Here's the result:

It's a set of 7" plastic lawnmower wheels attached to an axle (12" long section of 2x3") with a couple of ½ x 4" lag screws and some washers. Also attached to the axle, by deck screws, are a pair of support tubes (1 ½" PVC pipe cut to 3.5" long) that cradle the kayak and also provide a way to attach a strap to the cart. One of the support tubes has a gate slot cut into it to make it easier to pass the strap through. Total cost of this cart...about $15 (not including the strap).
Here it is mounted on my boat:

The cart is held onto the boat with the usual looped strap technique that you use to strap down a boat to a roof rack.
It's important that the forward part of the looped strap be prevented from slipping backward – I have caught the edge of my hatch cover on this boat. My wife's boat has recessed hatches so on that boat, I have to pass the forward part of the strap under the deck lines.
Here's a close-up of the support tube with the gate slot:

You don't have to put the gate slot in...a simple tube will work just fine. But you will have to thread the strap through it whenever you go to use it. With the gate slot, you can just pass the strap under – it saves time and frustration.
Here is the cart in both the front and rear hatches. This boat is a drop-skeg model and the skeg box takes up some room in the rear hatch. The cart was designed to fit into that tight area.

A final shot of the cart installed on the bottom of the boat, showing how the cart fits to the bottom of the boat with the round support tubes. My tubes are centered about 3.5" from the ends of the axle – I found that worked well with where I intended to mount the cart on our boats. Your boat may need different spacing – luckily, it's pretty easy to undo the deck screws and experiment with different configurations.

I've tried the cart out a couple of times now and been very pleased with it. After a bit of practice, I can install it in about 15 seconds on my boat. It takes longer on my wife's boat since I have to undo the strap loop in order to pass it under the deck lines – but I can still do it in less than a minute.
Since the cart is so narrow, it can go pretty much anywhere the kayak can, even down very skinny trails. If the forward strap is prevented from shifting back, the cart stays attached to the boat, even on rough ground.
I was concerned that the deck screws holding the support tubes onto the axle would let go but so far they have held up fine. If they look like they might fail, it would be pretty easy to replace them with small diameter bolts. If you intend to run the rig into the water a lot, you might want to spring for stainless steel or bronze for the metal parts and put some varnish on the wood.
Have fun carting! If you think of any improvements, please let me know.