I think I might be the first person to make and name these? though there could be somebody in Brazil who has been making bike trailers out of alupet tubes for 27 years! - If anybody knows I'd be really interested to find out! I first did these first around 2014.
Grab a can. Doesn't matter how tall. If it is full, drink it until it isn't. Cut the top and bottoms off. This can be done by first pushing a Stanley blade in and then using some decent scissors. Apparently cutting Alu doesn't hurt steel scissors.
Step 1: Re-roll Your Can Skin
Once you have your rolled rectangle of Alu, open it out and roll it inside out at 90 degrees to the length of the tube is the circumference of the can (fairly standard unless you drink that caffeine and Taurine crop).
Step 2: Roll It, Hold It.
Roll the can tight and get some washers over it to hold a uniform diameter roll. I like to use something around 15mm but up to 20+ and down to 10 can work, just has slightly different properties.
Step 3: Wrap It, Hold It.
If you don't have any PET string (as in Polyethertetrapthalate, not animal), then you can cut it with scissors (time-consuming) or you can make a PET cutter (I'll do another tutorial on this tool).
The technique is to wrap the string around the alu - tuck it in at one end and wrap up to the top and then back down again. I won't go into technique, but you'll get it! hold tight and both hand firm. KEY: ROTATE the TUBE to pull the string, rather than move the string around the tube. Slide the washers off as needs be.
Step 4: Spot It, Heat It.
Once you have wrapped, you can secure the end by tucking the end under the starting string and then welding (spot-melting) it with a soldering tip through both layers - use an old rubbish iron tip if you have one and keep if for plastic - they are cheap - and after melting, you can trim with a blade and then slowly heat shrink the PET sting with a hot air gun.
Step 5: Bind It and Build It and Mark It With B
You could make cubic stuff? Tetrahedral stuff is really nice and strong. you can join tubes together by threading with thick with PET string and heat shrinking again. You could use cable ties for ease, but that defeats the "Stuff From Waste".
The end blobs of melted plastic can be used to secure the end and make them smooth. These can be melted white Milk Bottle Platic (HDPE) or green / blue / red (the lids!) I have made a fair few things out of Melton HDPE - there are lots of vids and instructables for this I am sure :-)
You can also cheat and use low melton point thermoplastics like Polymorph or other branded cant-remember-the-name-of-the-plastic-molcule.
Happy empty recycle bins to you all :-)