Hi, I am designing a roller skate with wheels to the side of feet rather than underneath. The feet height will be lower than axle of the wheel, to allow the feet to be close to the ground. I want to try if this will result in a more stable skate.This means that I cannot have a continuous axle from left wheel to right wheel. Instead, each wheel will have its axle sticking out from the side of the shoe. The axle will be welded/integrated to the shoe. Shoe is expected to be plastic.I know this design will have lots of stress on the joints of the axle so I am doing some testing to find a suitable material for the axle/joint.I designed and 3D printed some joint models using PETG and put my weight on them, to simulate my weight on the wheels. They broke immediately. 3D printed parts are not the strongest but this is just a hobby project.Before trying to implement a aluminium axle/joint, can anyone advise is there a plastic that might be as strong as aluminium? PC? Nylon? that is still 3D printable? Please help. 
I didn't find the right solution from the Internet. 
References: https://www.engineersedge.com/engineering-forum/showthread.php/5228-Seek-advice-on-material-for-axle Blockchain app advertising 
Thanks 

