The boat is 9 feet long and weighs over 100 lbs by itself (and the trailer of steel pipe is not exactly light weigh). You can see in the video it maneuvers nicely, and is not a problem to tow (though I wouldn't want to take it up any steep hills!)
Step 1: Trailer
Step 2: Gimble Joint
(Darn Rust - it has held up well over the last 5 years since it was built considering I didn't paint it)
Step 3: Wheels
The axle is a 3/8" steel rod with holes drilled in the ends for cotter pins (with washer) to hold the wheels on.
There is a reducer pipe fitting on the inboard side of the wheels to reduce the diameter of the 1" pipe to provide a better fit for the 3/8" axle.
Note: a joining fitting is required at the center of the frame to tie the two side of the trailer frames together.