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Flexi Rex with improved links

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My print of Kirbs' model was not very kid-proof: one of the links broke after some rough handling. Hence I made all links more robust. This means this model can probably be printed even smaller than the original ones before the links become too weak. Of course you can also scale it up at will.

Licensing: note to anyone wanting to sell this

This model is released under a Creative Commons - Attribution - Share Alike license. You can sell prints of this model under certain conditions. The details can be found at

If you see this being sold anywhere without the required attribution, don't bother notifying me about it unless it goes far beyond the small scale of a typical Etsy or Facebook store. I don't have the time or means to hunt down all the unscrupulous people who want to make it seem as if they created this model and sell it at an exaggerated price. Moreover my contribution to this design is relatively small: Kirbs deserves most of the credit. If you do want to spread awareness about this model's true origin on sites where it is sold without attribution, post a comment there and link to this page if possible.

This model contains about 70 cents worth of material when printed in a premium filament. Add to this the costs of electricity and perhaps depreciation of printing infrastructure, and you might end up with $2 at most. Anyone who pays much more than that for a print is being ripped off.

Print Settings I've used

0.2 mm layers,
15% infill,
no supports and no raft, silver ABS

Pretty much any material should work. You could print it in a flexible filament to make it even more flexible and pretty much impossible to destroy, but plain PLA is probably easiest.

No supports needed. I used 3 perimeters to ensure the hinges are strong, this is much preferred over trying to obtain strength through infill. If you use too high infill, the model may become poorly balanced due to the head being too heavy. If you want to improve stability, use a higher infill for the piece with the legs if you can.

This should move freely right after you take it off the build plate. If you print with hairspray on a glass bed, the Rex should spontaneously jump into a random pose all by itself when it pops off the plate after cooling down. If you need to use force to free the hinges, you still have some optimization work to do on your printing technique.

This is not a demanding print. If this is one of the first things you're printing and it fails, expect other things to fail as well.

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