Locking Profile Snake (Rắn khóa biên dạng)

This flexible snake can be locked rigid for transferring profiles. Rather than using a fixed friction joint that is going to be finnicky and will loosen up over time, this snake-like chain can be made rigid by pressing the top links down onto the bottom links. The posts on the bottom links taper outwards towards the bottom, so that the fit gets very tight as you press the top link downward. Just wiggle the links a little to get them to loosen up again.

Both the top link and the bottom link are 19mm (0.75") long. Print them in pairs and then just snap the top link over the post on the bottom link, and continue to make a chain as long as you like. 

I suggest printing in PLA to keep it as rigid as possible. I used 4 perimeters and 0.2mm layers.