First, you need a frame to design your trailer around. Your options are to find a previously owned utility trailer and use that as a starting point. Or you can build one from scratch.
Garrett found a 4×6 utility trailer on Craigslist for around $200. While the frame was badly bent, the axle, hubs, wheels and fenders were all in pretty good condition. Plus it came with a clean title. So Garrett removed the axle from the original frame and built a new frame from scratch.
If you have a trailer already, start at Step 4. If you are building from scratch, begin here.
Step 1: Weld frame
Use the 2″ Steel Square Tube and cut the desired lengths based on your design. Also cut 45 degree angles at each end. The new trailer frame for this project kept the width of the original base, 4-feet, to allow for the use of the original axle. The length of the new frame is 7-feet to accommodate the design of the trailer (see step 4). Weld these pieces together to form the new frame. Test the fit and attach axle to frame using the 1″ x 2″ Steel Rectangle Tube to create the spacers between the frame and axle. Then weld them together.