How to assemble a monitor bracket with your own hands?

Question

Monitors

I'm sorry, not really an IT question, but rather a question for engineers.
How can you assemble such a thing with your own hands www.ergotron-russia.ru/products/desk/lx_new.html ? What details are needed for this?
I've found something similar, although it works only in one plane youtu.be/PQDdd1GFTzI
How can I replace the junctions to add more degrees of freedom?
Maybe there are some ball joints?
I'm just dead on my feet in this topic)
Buying these armas is expensive ( market.yandex.ru/search.xml?text=Arm+Ergotron), a toad will bite me, especially since I need 3 of them.
PS This is not exactly what I need - youtu.be/UtmsDxd-VXMbut I liked the presentation of the material. And all the materials for fastening cost 80 rubles.

Answer 1

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