History
This design is actually an improvement over an older publication, that can be found here: https://www.prusaprinters.org/prints/74889-tiny-carabiner-load-tested
Improvements over old design
During my load tests, I found that the carabiner always broke just opposite to the opening, which is actually quite logical. I figured there is no point in adding material in positions that are already strong enough, so I only enforced the part where it was needed. The result is this asymmetrical carabiner, which was able to carry around 50kg (500N) of load before it broke.
In addition to it's load carrying capabilities, this design was also optimized for the correct length and width of the spring mechanism. Printed in PETG, the spring should nicely bend all the way inwards, without permanent deformation.
Printing
Printing is fairly simple. Just use PETG and chose 100% infill. Print the part in the uploaded orientation.
I'd be interested to learn how much your prints can carry before they break.
Disclaimer
Don't be a fool please! This part is not for any application where live or health of any living soul is in danger or where material losses could occur.
Happy printing!
The author marked this model as their own original creation.