More pics of my two piece trailer. The intent was to leave the front part of the trailer attached to the car, unclip the trailer with two pins, then use the back part of the trailer as a beach cart. Since it's about a half mile across the soft sand beach to the water when I want to beach launch, I used to have to take several trips back and forth to the car to get stuff, it becomes quite a pain. Plus walking the HD scupper cart through the sugar like beach sand is very difficult (it's even a pain with the grey inflatable tires).
Here is the rear portion of the trailer (the 1" sq pieces would be removed to use as a beach cart).
Here is the front part of the trailer (would stay with the car)
Here is the whole trailer. Note the two PVC rails up the center, the boat slides on these rails, and is incredibly easy to load right out of the water (no scupper cart needed), or with the scupper cart in the rearmost scupper holes.
When using the unit as a beach cart (with the front part removed), The scupper cart would be in the front set of holes on the hull, then the cart is rolled up behind the boat and slid over then onto the cart (actually very easily done). The only down side to this method is you have to tilt the front of the boat up to get the scupper cart out (the trailers wheels are very close to the balance point of the boat so you are only lifting about 20 lbs).
The complete trailer currently weighs around 140 lbs and total cost so far was around $300 bucks. I have plans to replace all the red steel components with aluminum (about $100 bucks in materials) one of these days when I'm feeling ambitious. The whole trailer breaks down and can hang on the wall in my garage (though I will likely never do that, I just keep the boat on it, along with everything else (ie.. seats, motor, anchor, AMA's, etc) ready to go in the garage).
It takes about 5 minutes to back up to the water, pull the boat off, and have the boat in the water (ready to step the mast and rig the sails), quite a bit faster than my previous 30 minutes when hauling on the car top, with all the pieces in the back of the car.
All in all it turned out well, If I had to do it again, I would likely forget about the idea of the two piece trailer (will probably never use that beach cart option), but then again the option is there if I ever need to walk the boat a long way from where I have parked.
I also put in a caster wheel on the tongue so I can walk the trailer easily through parking lots, and in and around my driveway and garage.