I’m planning my first no-cook trek this summer on the Sierra High Route in order to go as light as possible, but wanted to have an emergency hot water system for potential hypothermia situations. So my primary goal was to make the lightest system I could that would boil 500 ml/2 cups of ice cold water. Canister systems are obviously out because of their weight, and neither wood nor alcohol are permitted in most of the Sierra Nevada. Although Esbits are not my usual fuel of choice they are by far the lightest option and they are allowed in the Sierra Nevada. They also work in the coldest conditions.
As usual (for me) I started with a Foster’s can modified with a 5.5 oz cat food can base. The flat base is thinner, lighter, more stable, and absorbs heat better, as well as allowing me to cut down the overall size of the can to match my capacity goal. The lid is cut from another cat food can because, amazingly, the grooves fit perfectly into the Foster’s top rim. The “handle” on the lid is ripstop nylon sail repair tape.
For the burner I used an empty aluminum tea candle cup.
The windscreen is a titanium gripper style, which is very effective as a windscreen and eliminates the need for a separate pot support.
Total weight: 1.6 oz

As you can see, the low intake holes are only on one side of the windscreen so that it can be positioned with the no-hole side facing the wind.
Pressed a ridge into the can at the 500 ml level for easy measuring:
Did four quick and dirty test burns. Used 7 gm (1/2 Esbit) to boil 500 ml of Brita-filtered ice water in roughly 15 minutes (60F outside temp, 30′ elevation). I played with the height of the can above the flames. With the can about 1.5″ above it boiled in 13 and flamed out at 15. With the flame 1/2″ above it boiled at 21 and burned out at 25!
Added a cozy for comfortable holding and to keep the water hot.
Added a cozy “hat” to keep it all together and for packing purposes:
Cozies look kinda sloppy but I was using scraps of Reflectix and tape and just making it for personal use.

here…
here are 5g.
