i think the most exciting part of this design is the laser cut bracket clamp.  you can rip off hundreds of these quickly, they clamp the emt tubing compactly, securely, durably, easily, cheaply, adjustably, and in-situ.  i'm new to lasers and wood is such a refreshing material option for these intricate shapes since it doesn't creep over time under load the way most fdm plastics do.  5mm 4x8 sheets and the emt is dirt cheap.  i can imagine this solution being useful in many situations besides shelves.  non invasive install using emt as a tension rod from floor to ceiling.

needed:
cheap laser and 5mm plywood
fdm printer and tpu and rigid filament
half inch emt conduit tubing
mini zip ties
the shelf itself cut old school wood elf style

stacking 3 shelf clamps in alternating directions, insert shelf bracket tabs and run a zip tie through the holes in the clamps and pull tight.  this fixes the bracket quite strongly in an infinitely positionable way (though still movable and fine tuneable with intentional force).  my brackets are tappey-tap-tapped together without fasteners or glue, but those wouldn't hurt.

cut the emt to rough length with cold saw or band saw or hack saw or zip wheel or karate chop.  the precise length as well as the fixing in place is accomplished with the screw adjuster feet.  the screw pitch is a standard 5 tpi painter/broom pole pitch, but xy scaled down .761 to fit inside the emt.  the tpu end caps provide a good smooshey grippy tension rod style anchoring between floor and ceiling.  (i wonder why do they call it a tension rod when it compresses itself in place?)

name is a nod to some of my favorite youtubers.  if you know who they are we can be friends.