One of the things I began to have an issue with last year when I was down here was at end of the day I would often have a dull pain in my right shoulder. It wasn’t disabling, but it sure was annoying. A couple Alieve tablets would help, but I think the real problem was carrying heavy loads in the backpack I used to transport everything everywhere. Sometimes it would approach 40 lbs. of cargo.
This year I decided to take another path. Since I ride my bicycle everywhere, I first considered a basket attached to the handlebars. But they were already full of things clamped to them. Lights, computer (speedo and odometer), cable lock, etc. Next I investigate saddle bags or panniers in cycling lingo. But there wasn’t anything available locally and even mail order I found limited availability for my Giant Revel 29er XL size frame. But I could have gone that route and had them shipped to Panama. But a more appealing option to me was to build my own trailer to tow behind my bike. Wheels and tires are readily available here as there are probably 10 times as many bikes on the island as there are cars.
After deciding on a size and configuration I ordered 1” square aluminum tubing and found a vendor that supplied all sorts of connectors that could join sections of tubing in an almost limitless configurations. These are the four types I used for my design.
This year I decided to take another path. Since I ride my bicycle everywhere, I first considered a basket attached to the handlebars. But they were already full of things clamped to them. Lights, computer (speedo and odometer), cable lock, etc. Next I investigate saddle bags or panniers in cycling lingo. But there wasn’t anything available locally and even mail order I found limited availability for my Giant Revel 29er XL size frame. But I could have gone that route and had them shipped to Panama. But a more appealing option to me was to build my own trailer to tow behind my bike. Wheels and tires are readily available here as there are probably 10 times as many bikes on the island as there are cars.
After deciding on a size and configuration I ordered 1” square aluminum tubing and found a vendor that supplied all sorts of connectors that could join sections of tubing in an almost limitless configurations. These are the four types I used for my design.
I ordered this Heim Joint for use as the articulating hitch point which needed to both turn and tilt as the bike rounded a corner.
Heim Joint Allows Articulation In Multiple Plains
I also purchased two 26” bicycle wheels and tires locally. About 2 weeks later the tubing and connectors arrived from the USA via my Mail Boxes Etc. account. I started to cut the tubing to the various lengths required to assemble my frame.
The two narrowest rectangles on either side of the frame will form the supports for the axle cradles where the wheels will attach. The rest of the tubes form the frame of the cargo box itself. To one end of the frame I attached a single 18” length of tubing. At the end of this tube I attached the Heim joint using a long bolt whose threads matched the female threaded socket of the joint. I cut a 3” length of wood cut to a size that would just fit inside the square tubing. Then I drilled a hole lengthwise in that piece of wood that would accept the bolt that was screwed into the Heim joint. Once this assembly was finished I inserted it into the tubing and secured it with a bolt running through the inserted wood/bolt assembly and the tube itself. To the threaded male post of the Heim joint I screwed on the female half of a compressed air hose quick coupling.
Frame With Wheels Attached * Starting To Look Like A Trailer
Next I needed to make the portion of the hitch that would be fastened to the bike’s frame. I started with a piece of 1” steel angle iron. I would need to bend it into a “U” shape about 18” long by about 6” wide. I first notched the corners of the “U” so that it could be bent at those points. Then I drilled a single hole at each end of the “U” where in would be bolted to the frame of the bike using the provided holes in the bracket to which the bikes rear axle attaches. In bicycle terminology, these brackets are called “dropouts” and they typically come with a threaded hole in them that can be used to attach fenders or a rear luggage rack. I next made two cables with an eyelet at each end. One end would attach to the “U” shaped hitch frame at the back. The other end of the cable would attach to another predrilled and threaded hole in bike’s frame by the seat post. These cables support the outer end of the hitch frame. Finally, I drilled a hole in the center of the narrow length of the hitch frame and attached the male part of the air hose coupling. Now the trailer can be easily be attached or released from the bike.
Next I would build the cargo box that would attach to the frame and hold whatever I wanted to haul in the trailer. To keep weight low I used a ½” thick honeycomb panels which I then covered with a single layer of fiberglass cloth on each side of the panel. Frustratingly, it took two months to acquire the 4’ by 8’ sheet of this honeycomb panel from which I would build the cargo box and its top or “lid”. I’d never worked with fiberglass before and this certainly was a learning experience. I initially had problems with the epoxy resin which binds the fibers of the cloth to each other and in this case the panel they were covering. Being an epoxy resin, it comes in two parts. The resin and the catalyst that in this case were mixed in equal quantities. But in my first attempt, I failed to mix the two parts adequately. They looked well mixed, but such was not the case and the mixture failed to set up properly. I later learned to mix the resin for a full 5 minutes to insure adequate mixing. The box itself consists of one bottom panel, two side panels, and two end panels. They interlock with each other at the corners and then screws secure them to the frame tubes.
Honeycomb Panel Before Being Covered With Fiberglass
Next I built the top or “Lid”. Think of a large oblong cake pan turned upside down. The “bottom” of the pan is about 1-1/2” smaller in length and width than the top of the box and the sides are angled out so that the “top” of the pan is roughly the size of the top of the cargo box. I used the same honeycomb material to make the 5 pieces of the lid. Temporarily I used duct tape (you can’t be a craftsman without duct tape) to hold the panels together on the outside surfaces. Then, using fiberglass matting and resin I covered the inside of the pieces and let that cure for a couple of days. Then I removed the duct tape and this time using fiberglass cloth, I covered the outside of the lid.
The difference between fiberglass cloth and fiberglass matting is that the cloth is actually woven just like traditional cloth. The matting is simply short pieces of fiberglass strands pressed together in random directions.
The difference between fiberglass cloth and fiberglass matting is that the cloth is actually woven just like traditional cloth. The matting is simply short pieces of fiberglass strands pressed together in random directions.
Matting is much easier to form around irregular shapes. This made it easier to form to the inside of the lid as the fibers could be worked into the edges and corners of the lid. On the outside of the lid it was easier to use the woven cloth to mold over the edges of pieces. Even so it took lots of trial and error and redoing to get a relatively smooth surface on the outside of the lid. I still wasn’t satisfied with the smoothness of the top and I had to use epoxy body filler to get to the finished surface that I could be proud of. On one end of the lid I fiber glassed in an aluminum bar with the ends bent out 90 degrees that would serve as one half or the hinge for the lid. The other half of the hinges were fashioned from two eye bolts attached to the frame of the trailer. I then installed hinged struts like you might find on the lid of a piano bench that support the lid in the open position. On the other end I installed to lockable latches to secure the trailer’s cargo.
Trailer Ready For Loading
Let's Haul Something
This is a project that has taken almost the whole of the time I’ve been here to complete and I am most pleased by the outcome. But if I had it to do again I would pay the money and buy one of the commercially available bike trailers. I would estimate the cost of the materials alone close to $700. Maybe more if you include shipping costs for some of the materials. And though I certainly didn’t work full time on this project over the 8 months I’ve been here, I’m sure I have over 100 hours of labor involved. I learned new skills. The biggest involving fiberglassing. But the biggest lesson I learned about fiberglassing is that I don’t want to do it again. It’s messy, tricky, and almost impossible to keep little shards of glass from getting imbedded in your skin. And it takes days for them to be dislodged. Ouch!