DIY Caldera Cone enhancement

[2Questions]

I made this CC a while back and have been using it for a while now. It makes good sense for an alky burner incorporating a pot stand as well. I question whether I can improve the system by figuring out a way to add a heat exchanger to the bottom or sides of the pot. I've seen some attempts here on the forum but yet to see one in operation that works well. Can some of you engineer types help design an exchanger, preferably portable and lightweight that can capture those lost BTU's.....yeah, I know, the same ones that keep my hands warm in the fall mornings as I'm prepping for breakfast.

[Shug]

That is sweet! Is the pattern hard to make? What material did you use?

[2Questions]

Yeah, it is sweet. I love the simplicity of it. Since this picture was taken, I've removed my handles off my Ti pot and fabricated new ones that are higher up on the pot. Less heat loss from the caldera cone. The cone is made from Home Depot aluminum roof flashing. The pattern was stolen from somebody here on the forum. Do a search and you'll find it somewhere. It was basically simple once you lay it out right. I went through a couple feet of wasted flashing until I got the fit to my pot just right. The holes were made with a regular paper hole puncher. It stays together via matching folding bends. A small hole drilled through and a clip assures it stays together. I roll it up and place it in a small plastic container with my stove, fuel, lighter, spoon.

I did have a picture of the new pot handle.

[Take-a-knee]

Trying to make a Caldera cone "more efficient" is like trying to make a Porsche or Corvette faster, what is the point?

[2Questions]

I was thinking of the jetboil system and the exchanger it uses and could anything be gained to capture the lower Btu's of alcohol. No other point than that..., but that is often the case with an addicted "tinkerer" whose imagination often goes beyond practicality I guess.

[LostCause]

thinking of the jetboil system and the exchanger it uses and could anything be gained to capture the lower Btu's of alcohol.

here are my two cents:
I think the whole idea of needing a heat exchanger is because of the low efficiency of burning high BTU fuel under limited surface area. The heat exchanger increases the surface area of the pot.

Because of the lower BTUs of alcohol, a lot of the heat will be absorbed into any heat exchanger on the bottom of the pot slowing the transfer into the pot itself. It would probably take longer for the water to boil if it boiled at all. The plus side to that would be that the pot would be warmer longer. But then again, I've never tried to boil water in a jetboil mug with a alcohol stove.

I think that you could probably put some bent flashing on the sides using a similar pattern to the jet boil system, but they would probably have to touch the pot to do any good. This would be useful for the stoves that shoot flames up the sides of the pot, but if you are using a stove that centers on the bottom of your pot I don't see it working very well. Also, that means you will be limited to the pots you can use with your cone.

But I can't see doing it without adding a bunch of extra weight with limited results. The cone should already allow more transfer of lost heat than a normal windscreen/heat shield because of the tapered top.

If you try it, let us know about the results. Sweet job on that cone though! I'm not that good working with metal.

[2Questions]

Your theory on the exchanger rationale sounds very reasonable. Actually, now that I've limited the amount of heat that escapes around the handle of the pot, I'm quite happy with it. Before I'd burn my fingers lifting it out of the cone. That doesn't happen now. Thanks for the reply.
2Q

[Take-a-knee]

The only thing I can think of would be to make the cone from a material that didn't transfer heat as efficiently as AL. I have no idea what that would be, and it would likely be too heavy or otherwise unsuitable.

[LostCause]

Well you could wrap the cone with fiberglass or some other sort of insulation, but packing it down might be an issue.

What about a layer of High Temp silicone? Not sure if it would stay on the cone, but it would help insulate to some degree.

[gnome]

I made a cald. type cone with light titanium. is easy to work with scissors. Used pop rivets to fasten. tough stuff and very heat resistant, al. will burn over time and hi heat.
keep it light and simple, gnome