Heat Exchanger Pots are becoming popular as they are supposed to boil water faster and do it burning less fuel than regular Pots do, but XC Pots are considerably heavier and considerably more epensiv and are not available in Titanium Pots.
But what if there was a way you could set a Carbon Felt Pad on your stove and set the Pot of your choice on top of that pad and get the same kind of results as with Heat Exchangers?
What is Carbon Felt? Carbon Felt is sold at Home Depo in the welding supply Department to protect heat sensitive things that are close to where Torch Cutting, Welding and Soldering work are being done. Carbon Felt does not burn, is soft, pliable, and can be used as a wicking material to make Alcohol Stoves with, and is fairly light in weight, but somewhat expensive. And a Carbon Felt disk placed in the Flame Opening of a Heat Exchanger Pot may make that pot boil water even faster than it does without it.
The first I heard of Carbon Felt was in the making of Hiram Cook’s Fancy Feast Alcohol Stove, which uses a Fancy Feast cat food can as the fuel cup, and a Tomato Paste can as the pot stand for the stove and to wrap the Carbon Felt around to form the stove’s wick. Why he chose a Tomato Paste can I have no idea. There are a number of aluminum beverage cans available that will not rust and transmit heat better than a steel can will. What ever can is used needs to be cut at the length that will give a 1” fuel cup top to Pot Bottom Distance for optimum boil times at 1” or better. If V-8 or Clamato cans are used to get an aluminum pot support, with a little more work the can can be inverted so that the concave bottom ends up on top of the stove and forms a fuel funnel by drilling a 7/8” hole in the can’s bottom for a stronger more finished looking stove. Regardless of which can you use, Pressure Ports need to be punched or drilled in the inner can near the top to prevent over flows and alcohol fires.
I prefer to use a Pot Stand for the fast boil time mode and build the stove to the Simmer Ring height. Using the inner can as a pot stand shields almost 4 square inches from flame on the pot’s bottom and eliminates the need for a Simmer Ring. And with the shorter configuration, the flame pattern changes from a hollow cylinder to a cone shaped one that covers the whole pot bottom.
After Hiram started building the Fancy Feast stoves with Carbon Felt, he began experimenting with it and found it had a number of other uses, ie it made great pot holders for handling pots with boiling water in them. He used a tall, skinny pot, wrapped the CF around it, held in place with 600 degree safe silicone rubber bands. An infrared thermometer clocked the pot exterior at 400 Degrees and Hiram could handle the pot bear handed Touching only the Carbon Felt.
Hiram also ran a Wind Screen test of CF against an aluminum wind wind screen. Because CF wicks alcohol it is not wind proof but it did prevent a 6 MPH fan breeze from over powering a Super Cat stove’s flame, but the aluminum wind screen did a better job, although it weighed 3 times as much.
Hiram used a CF square as a spacer to prevent burning of a muffin in a pot for an alcohol stove oven and it works well with the Trangia Burner. But with a Cross Pot Stand the heat got too hot, so he placed a CF disc on top of the pot stand and the baking pot on top of that for a boil test. Strangely, the water boiled faster with the CF on top of the cross stand than it did with out the CF disc. What I believe happens is that the somewhat Porous CF slows the flame’s down enough that more time in flame contact allows more heat to be absorbed by the water in the pot than can be absorbed with out the CF Disc.