Materials: smallest size aluminum tubing, from the Ace hardware hobby/craft metals rack (smallest tubes come ina 3 pack). Do NOT try to find this in Home Depot, you will only get blank stares and ignorant responses. Aluminum wire, less than 1/16th inch thick. Aquarium filter bags, nylon. 1/16" drill bit and drill. Pliers, to squeeze tube ends flat and bend aluminum wire.
I was using a normal large sized tea ball, but it took too much room in my narrow pot with the other stuff in it, so I wanted something smaller. Obviously the 18 grams I saved makes no real difference to anything in the real world, but the size did. The mesh dries super fast, stick that on a rock after you dump the tea and it will be dry by the time you pack up your breakfast/dinner stuff. That's why I didn't use a cotton, plus cotton will stain and retain flavors, which is of course undesirable for teas of all types. Also, polyesters I believe should not be used in boiling water, or near boiling, too close to their melting points. Nylon mesh and nylon thread. For this prototype I used polyester thread, but for a better one I'd use nylon thread too. I researched the temp ratings of the different materials, and it turned out nylon is the only practical choice.
This mesh material is hard to sew (much harder than silnylon), and the way the stuff folds isn't intuitive, so it's worthwhile making a pinned mockup with muslin or something, I wish I'd done that. This is a raw prototype, I didn't really test the sewing tensioning, as you can see, but it works well enough for me to use it. Made this yesterday after being bugged by tea ball for a while.
Tea ball has annoying habit of opening when you pull it out, thus spilling its contents, and it also doesn't really have enough room to let tea expand and really soak in the water. I'd make the above bag bigger next time, it's easy to make new bags, just slit them, then slide them on rods.
I wanted to use titanium rods, but the local bike shop didn't have titanium spokes and finding rods is too time consuming so I just used the softer and more flexible aluminum tubing, which is super easy to work, and drill through.
I may, if I get motivated, make these for sale if I can clean up the design and sewing parts, and if I can find titanium rods, this aluminum is fine but you cannot treat it non-gently.
I believe 1.4 grams qualifies for 'really lightweight', and it is reusable, so this would meet the specs. It's tricky to make it though, the previous prototype got swallowed by my sewing machine and almost destroyed the machine, had to take it all apart to get the stuff turning again, had to pull out the ripped and shredded material with pliers, then dismantle the machine. So be careful with it.