Brutalist Bike Trailer

[Philip]

Here is another picture I took. Which I did not think about doing yesterday. There was no cracking when I did that extreme bend the picture shows.

[sgraham]

Here is that 12"x12" sample I said I would make. Thickness .040"





This is a waterproof sample. It does flex. It would hold whatever shape you mold it to. It does have moderate impact damage. Weight on my cheap scales came in around 0.50 of an ounce.

Don't pay any attention to the pattern in the epoxy. I did a fast layup on a black trash bag not thinking about the pattern the plastic had in it.

That's very cool, thank you so much! I got some cheap 2.6 oz weave nearby to try to reproduce this here, and ... did an absolutely abysmal job, more bubbly parts than there were flat.

After some more testing, I do agree that light fibreglass seems like the most appropriate material, but I would definitely need to get more skilled at applying it.

[ghcoe]

I looked at a lot of commercially available bicycle trailers in Europe before I started my build. I wanted to get my head wrapped around their designs and dimensions. Most were teardrop in shape and about the same size as your dimensions. I would not overthink the arrow dynamics and side wind load that much. Just build it and go from there.

The reason I chose my design is that a boat travels by design well through water. I basically flipped a boat upside down. Having a pointed nose does help with head winds. It will also save you from a trip over the handle bars if you should hit something head on with a flat front wall. Having a flat back will push you with a tail wind. Also, having a slight side wall cure from front to back creates a lot of strength into the wall.

In general I don't like fiberglass. It annoys me. I have worked with it, but once I did PMF I wont go back to FG unless I have to for some reason. Foam and PMF is plenty strong and light for bicycle trailers.

Good luck, George.

[woodie72]

Wind drag.

With bicycle trailers this is negligable. In the scene many are going straight sides, rectangle boxes, vardo style, etc. There are no complaints about wind drag. In headwind, even without trailer riding is heavy so that's moot as well.
This guy, https://www.youtube.com/@Therapeut_on_Tour, traveled across Europe and built a new wooden trailer when he went to south-america. The thing weighing 100kg, vardo style with straight front and back did not have any complaints whatsover about wind drag and he went no electric in South-Anerica.
This guy, https://www.youtube.com/@andrzej-bike_camper with again a lot of experience in the field also went straight sided vardo. And many more are doing the same.
And again this fella, https://www.youtube.com/watch?v=xgSSVD3GsPw travelled about 2000km's with a vardo style trailer, straight front and no electric assistance. His original trailer weighted about 180kg's all laiden.

Wind drag is a drag of a topic and in practice a non issue. Weight is much more of an issue.

Myself i am going for the Runaway style camper, 5cm foam floor and 2cm foam sides. Floor was sandwiched between 6 oz fiberglas and the sides and roof will be cheese cloth/muslin with tb2. A cutout in the floor where i will put my feet when in sitting position, will enable the overal height to be lower.

I am shooting for about 25kg for a 210 cm long by 90cm wide trailer on 20 inch wheels. At the moment for the floor, wooden trailer, wheels and supports i am at 15kg. This way i can forgo making it a braked trailer.

The exposed parts of the foam floar will be covered with foam childrens puzzle/play mat.

[perec4stor]

very very nice! love the idea!

[KeyanSammy]

Hey! Welcome to the community, and congratulations on catching ""the bug"" for building a foamie bike trailer! It's okay to start with more elaborate designs, but simplicity can have its charm too. Your brutalist approach sounds intriguing!
Just remember that if you experience issues with this vehicle, you can count on platforms like db fahrplan to get where you need to. Good luck!