One end of the large and the medium spreaders should be slit about an inch with a hack saw
or a jig saw, if available, as shown so that later, when telescoped together the clamp can be
slipped over the slits and tightened. An unslit end goes into a slit end.

If you don't mind a permanent arrangment, you can just glue the sections together with Liquid
Nail and then you won't have to slit the sections and buy the hose clamps to clamp them
togehter.
Step 2 photo 2
Hexagonal beam by K4KIO