Same brain-itching here... Why does heating up the tank significantly reduce power?

Gravity might play an important role: when the tank is at 1/4, power also reduces, compared to 1/1. But really not so much, by far not as much as the heat issue.

To your thinking of heat expanding, I do not quite agree: though ethanol has a 5.5 times higher heat expansion coefficient than water, its mass stays the same. Gravity only cares about mass, not volume.

Yeah, charging or even supercharging... I have to admit that I am afraid of that. I decided for a gravity-fed burner instead of a pressurised petroleum burner just because of the fear of pressure-spilling highly inflamable, hot fluid into my precious Ilvy... Probably this is overthinking, but still. And also: that Salsa device is not meant to be pressurized, and also not meant to be overheating that much. Pressurizing it would feel like not only not dealing with the overheating, but even more, increasing the load on the burner. Haha, I don't feel like this is a good idea.

Anonymous wrote:

Paul,

have you tried to cool the tank with a wet rag, just to see if that causes the power drop?

Arne

Yes, indeed. First with a wet rag, which already helped a lot, but did not last long as the rag warmed up rather quickly. For improvement I looked for something with a higher thermal mass - and found a plastic zipper bag. That tiny little bugger, filled with cool seawater and stuffed behind and under the tank, lasts significantly longer. But still, this cannot be the final solution, its still a prototype. 

I guess the stainless ikea dish plays a huge role in the problem: free air circulation is restricted a lot in my setup.

Anonymous wrote:

I picked up one of these to replace my standard gas. Delightful thing from Toplicht called Mambo 2 for just over €100

, called "HPV Salsa". It fits perfectly into a stainless dish from Ikea, which prevents any bigger damage if ever some spilled ethanol ignites. The preheating device in this Salsa thing looked quite dangerous to me...

Also, I pimped it up a bit: into the refill screw, which originally just a plain open hole for ventilation, I installed a grease nipple. Onto this nipple I put a grease nipple cap, whenever we go sailing, so that no ethanol might be spilled due to heeling. And I added a aluminium rod, to fasten standard pot holders if needed.

The Salsa works okay. It could have a bit more power for roasting. Interestingly, after 10-15 min the power decreases significantly while the device housing and tank ist getting hot. I suspect it does not like the ethanol getting warm in the tank, but have not yet understand why.

Just as a little follow up in case anyone is interested. 

I stripped off all the gas gubbins from the existing stove,  the Mamba fitted in perfectly so I now have a perfectly gimballed alcohol stove.

Perversely, the yard where I am doing my refit were landfilling some abandoned boats from one of which I salvaged a perfect Origo 3000 totally free of charge. 

With one of the spare burners, I am planning to create a working oven. 

Here's a heart-warming little clip of a Trangia in action.

https://www.facebook.com/reel/3238834966355159

I bought one of these, it was quite inexpensive. When I get a round tuit, I'm going to set up a match-race between that and the Origo.

You've gotta have the gingernut biscuits.