Caffin Winter Vortex Burner Stove

[Roger Caffin]

I know about the Nansen stove and the modern version, but if you look carefully you will see that the system does have a large exhaust port as a large diameter vent right around the pot. The large diameter counters the narrow gap.

My experience with some of those older designs for kero stoves has been that they are considerably less powerful than the modern canister stove. I have found it very hard to get a kero flame as large as a butane flame: little over 2 kW (kero) vs 3.3 kW (canister). That might be a bit surprising, but I think it is due to the difference in the number of carbons in the molecules, and the difficulty of getting enough oxygen mixed in. So they generate less exhaust gas.

The converted milk boiler is an interesting idea. We would all love some test results and measurements – please!

Cheers

[DAN-Y]

And in the end they all melt snow and will boil water :-)

The original modern design:

[Pierre Descoteaux]

<p style=”text-align: right;”>Milk boiler! Never thought of that. Testing needed indeed! Thank you for sharing.</p>

[James Marco]

Yeah, in the past 100 years or so there have been some really good designs to wrangle every last bit of work out of a stove.

[DAN-Y]

Lookd like 4 holes for intake air on modern enclosure 2 not visible

[DAN-Y]

I purchased one of these heavy pots last year for large family car camping gatherings :-)

[Roger Caffin]

Four small air intake holes are probably enough, considering the jet size. But you need a huge amount more outlet area to cope with the hot expanded combustion products plus the hot expanded nitrogen gas. Without a good exhaust the flow in gets choked and the CO emission rockets.

Yeah, my pet hobby horse, I know. But people have died from the CO before.

Cheers

[DAN-Y]

I know your concerns, really I do, honest injun. I’m a beliver, yes I am for sure. I’ll be melting snow outside and I promise to increase the amount of exit holes at the top of the pot support/windscreen.

Edit to add:

My wanting to use a remote canister in a confined space is not new.

Roger, I want to use the stove inside the confined space of the windscreen/pot support, not an enclosed tent.

[Roger Caffin]

Hi Dan

I am being paranoid, I know.
It may be that the conditions in our Alps are different. In the photo below the snow storm outside was clocking up to 100 kph, and there was no way anyone would have been cooking outside. The stove would have blown away, for a start! And the cook would have frozen to death. Um – in hindsight we should have retreated fast.

But maybe such conditions don’t apply for you? Lucky!

Cheers

[Pierre Descoteaux]

Dan, what is the volume and weight of your modified milk pot? Thanks

[DAN-Y]

Those are the concessions you have to make at your age 

Noticed you have no incoming air holes in your windscreen. What’s up?  I’m paranoid now……………………Stay safe!    Won’t bother you anymore. Got notification from Amazon the the Kovea Spider is in the mail and will be preoccupied.

[DAN-Y]

@pierre,Dan, what is the volume and weight of your modified milk pot? Thanks

 

I’m not in posession of the pot nor was it my project.The volume of the aluminum pot is 1.5 litre milk pot. Follow link to inventors site:   http://matej.boha.cz/milk_pot/

Pierre, is the snow pure enough, where you climb to, not to boil your water, only bring it to 180 degrees to pasturize it? Maybe you only need to pasturize to save on fuel consumption.

Do you cook or rehydrate prepackaged meals?

[Roger Caffin]

Hi Dan

No, I don’t have holes in my windscreen per se. Instead I have the windscreen going only 3/4 of the way around the stove, with the ‘back’ into the wind, as shown here:

Mind you, inside the tent, which is where I always cook, there is not much wind anyhow. I think this must be a V1 winter stove.

On the purity of the snow issue: we have never treated either melted snow or snow melt. We do not see either case as justified.

Cheers

[Pierre Descoteaux]

Hi Dan, I was revisiting this older post and saw that I did not answer your last questions. I usually re-hydrate home made dehydrated meals in a tupperware. (I have not tried zip locks yet… ). Otherwise, I do not need to boil since it usually is clean in the Canadian wilderness. A huge country with a 10th of the USA’s population… It has some advantages…

I’m still hoping to find an ultra light 2 liter version of that pot!

Cheers.

[Roger Caffin]

Hi Pierre

MSR make a 2 L Ti pot. Example at
https://www.moontrail.com/cookware/msr_ti_2literpot.html
Seems to come as a pot set for $150 at MSR, not as a single.
Kinda $$$ though.

We use a 1.4 L Ti pot (seen in pics) for the 2 of us – quite adequate.

Cheers

[Pierre Descoteaux]

Thanks Roger, I was referring to the double layered milk pot. How about an exterior pot in thin Ti and the inner in as thin as possible Al. Light and better heat transfer… I just can’t afford to buy two Ti pot in the hopes that I could do such a mod. I do not have Dan Y’s skills… An Al milk pot in the right volume (close to 2L) would be very attractive.

[Roger Caffin]

Ah – double-layered. I missed that part.

Jetboil tried to weld aluminium to titanium with some of their early heat exchanger pots. Turns out that welding Al to Ti is extremely difficult, and the aerospace industry tries hard to avoid the need. Jetboil claimed they had solved the welding problem, but I did not believe them and events showed that they were either shooting their mouth off or fooling themselves. And I would emphasise that you can NOT spot weld them together – I tried.

If you want to make such a weld reliably, I think you have to use electron beam welding in a vacuum. The costs for that are a bit high. :)

In fact, welding Ti to Ti is considerably cheaper and simpler, as I think you can do that with TIG (some skill needed). I KNOW you can buy Ti welding wire/rods, as I buy them myself.

Cheers

[Pierre Descoteaux]

Yes, thanks for the reminder.  I forgot the JB issues. I’ll stick to sewing and won’t venture into welding for a while longer if ever… Modifying a cheap Al milk pot seems to be the option here.

Cheers

[DAN-Y]

Would a 1.5 litre modified milk pot work for you Pierre ?  I can purchase a few and modify them.

[Pierre Descoteaux]

Do you think their base width would suit the Caffin Vortex stove? I’ll see how expensive it would be to get one shipped up here in Canada. I should be able to do that type of a mod myself with an Al pot. But it won’t be as pretty as the work you do Dan! It will be smaller than what I had in mind but lighter and more compact.  Always some trade off…

Thanks for the offer.

[DAN-Y]

Ok, have fun with the project. I’ll order one for myself to play around with on rainy days :)

Roger, what is the spread of pot supports on the Vortex stove? I’m in the process of working with Toaks 650 pots, making skirts that fit their 102mm (Dia)

[Roger Caffin]

what is the spread of pot supports on the Vortex stove?
That is where the brilliance of my latest (V3) design shines (ahem, cough). As you can see here, the pot supports cover a huge range.

The inner diameter (between the ends of the supports) is about 45 mm. The outer diameter is >135 mm. So most any pot will sit on this stove.

For the V2, with a triangular pot support, it depends on whether you have the standard size triangle or the mini. For the standard triangle the minimum diameter would be >75 mm – with some care. Bigger would be more stable.

Do you have an English wheel or similar, for rolling the edges over?

Cheers

[DAN-Y]

Thanks Roger! Yes, a modified English Wheel does nicely.

It will be smaller than what I had in mind but lighter and more compact.

There is a 2 litre stainless steel milk pot out there.

[DAN-Y]

Roger, do you think the amount of holes in this modified milk pot is overkill if used used with the smaller canister stoves?

[Roger Caffin]

Hi Dan

I am guessing that the visible pot conceals an inner pot sitting on the ends of the stove support arms, and that it is meant to act as a super windshield. Cute.

My gut feeling is that the outer pot has enough ventilation, but I would be very reluctant to reduce the number of holes by much.

Anyhow, what a nicely polished old stove you have there! Is it a genuine Primus 210, or a modified one? I ask, because the legs seem to belong to one model while the burner belongs to another model, although maybe the burner shield has just been removed. And it looks as though the pump has been (re-)installed with soft solder – is that right? The pumps I have seen were fitted with bushes into the tank. Perhaps the bush failed? I would prefer to have silver-soldered it in myself, but that is harder.

Cheers

[Author]

Posts