Some loads are just too awkward to take on the back carrier, but to hook up the trailer seems overkill (certainly when it is disassembled in the attic).

This carrier can be installed or removed in 5 minutes.

Needed: (part of) hand cart
4 nuts & bolts (M8 or so)
2 plastic furniture caps
part of inner tube

Tools: drill
hacksaw and file
vice
paint stripper, primer, paint

Step 1: Handcart

I still had the frames of 2 handcarts, bought for the axles + wheels to make a 4 wheel trailer.

There always needs to be an immediate reason to start the creative juices flowing; in this case I have only one good crate and loads of Dahlia bulbs already dug up. Frost is predicted in 2 days.....!!!
The 4 wheel cart is able to take everything in 1 or 2 rides, but I don't have the proper containers. Better to take 1 crate at a time, and ride 4 or 5 times....

The first idea was to rent a pipe bender and assemble the carrier from 22 mm or 15 mm steel conduit pipe. It would require soldering or brazing, with quite a few Tees and Ls or welding. Welding could be done, but 20 years without practice would almost guarantee burning holes in the pipe, poor welds, and gaps for water to enter.

Anyway this is soo much easier:

1: Cut the handcart frame to the proper size

2: The lower part will be used

3: Take the 'fenders' off ( these are steel plates on the sides to protect the wheels). Bending back and forth a few times broke the spot welds). Finish the sharp edges.

Step 2: Bracket and Assembly

One of the 'fenders' is used to make the holding bracket. The part of the bike which seats the handlebars + front wheel holds the carrier. The carrier does not follow the front wheel, but is rigidly attached to the frame (which is very confusing during the first rides!). The plate can be bent halfway around a pipe, or bar (similar size as bike frame). In a vice, the outsides can be bent 90 degrees, to get a bracket (omega shape).

4 holes have to be drilled in the bracket, and corresponding holes in the base plate.

To protect the bike frame, the bracket is covered with a piece of inner tube; the same is done at the base plate. Of course the paint has been cracked by all the bending: it has to be stripped and the whole thing needs a good paint job!

Step 3: Tuning

In my situation, the base plate as well as the bracket were too long. the distance to the front wheel was minimal. It required some more cutting and repositioning of holes in the base plate. The base plate is rather thin (2 mm), so at heavy loads, the carrier flexes toward the wheel. For reasonable loads, moving the carrier upwards solves the problem.

At the front, 2 wicked pipe ends protrude. 2 caps, found at the legs of cheap office chairs, provide safety and protection from rain entering the legs of the carrier.

Step 4:

So.. after a few days of use, I decided to strengthen the L connection between the base plate and the rack. The transport carrier is OK, but the base plate is the weakest link: it flexes too much.

I got a steel strip (3x 30 mm), and bent 2 square supports (after cutting). I had to take the carrier off the bike for stripping and painting anyway. The hand carrier already had 4 M10 tapped holes for the axle supports, corresponding holes were drilled in the support brackets to connect . 6 mm holes were drilled in the brackets and base plate for connection with M6 bolts.

When the paint is dry, I want to glue rubber (inner tyre, flooring, insulation) on the parts which come in contact with the cargo. Pics will follow.....

Step 5: Alternatives..

Not everyone has a scrap handcart... If you only have pipes and some sheet or strips of steel, the basics are as follows: A rack and something square solidly attached to it to fasten. The square part needs to be sharp, not curved; otherwise the load is difficult to fasten.