Fire Umbrella:

How to prevent the rain from putting out your fire? I have been toying with this idea for some time. This week I decided to try out an ‘ultralight’ method. I constructed this 1 metre x 1 metre square of tyvek for that purpose, sewing gross grain ribbon tie outs on each of four corners. This ‘fire canopy’ weighed less than 2 ounces (60 grams) including the 1mm (pink!) dyneema suspension ‘rope’. This is not much weight to carry for the benefit of a warm fire out the front of your tyvek tent or shelter.

Before:

The ‘apprentice’ seems very pleased with the arrangement.

When I was up the bush on a training trip this week with a new ‘apprentice’ (you can expect a future post ‘The Deer Hunter’s Apprentice’) some decent (?) rain set in so I thought I would give it a try. To begin with it worked a treat, so the ‘proof of concept’ is definitely ‘in’. After a little while someone became a little enthusiastic about putting too much wood on the fire (and ignoring it) so that the flames were actually ‘licking’ the tyvek (well ‘devouring’ might be a better word), which didn’t like that so much. Clearly naked flame exceeds the melting point of the tyvek so that it now has a large hole melted in its centre. This could have been prevented by having it suspended about two feet higher and/or not building the fire up so much. The tyvek did not ignite! An important point. Also importantly, the ‘string did not melt, only the hottest centre bit of the ‘umbrella’. I belatedly shifted it higher and left it there and it melted no more, yet still prevented the fire from going out – which it probably otherwise would have.

The other strategy to use would be to source some more fireproof (though heavier) material. The stuff that ‘fire blankets’ are made of would be very good, though also very heavy 427 grams. The fire blanket must be made of approx 13 oz cloth. I see that they (https://www.auburnmfg.com/product-category/mro/heat-resistant-cloth/) also make a 9 oz product which would bring the weight down under 300 grams (still too heavy for my liking). Of course both heavier materials would be fine for car-based camping. More to come…

After:

See also: http://www.theultralighthiker.com/fire-tent/

A reader responds: ‘Interesting idea. I’ll warn you that the column of hot air — hot enough air to melt synthetic fabrics — extends an alarming height from any fire large enough to keep you “warm” without having to sit so close to it that the embers won’t make you and your stuff Swiss cheese. I see many possible failure modes for this plan, and most of them involve picking molten plastic off of yourself and/or your gear. The current conditions including wind, etc. are going to make the performance of what that hot air is doing extremely unpredictable, as well. It wouldn’t take much of a breeze for the heat to be shifted enough to take out one of your guylines. You are also in a catch-22 situation: The higher you hang the tarp to keep it away from the heat the less effective it is versus rain blowing in from the sides. So the bigger you make it to mitigate this the more heat it captures, so the higher you have to hang it, so the bigger you have to make it… etcetera.

Flame retardant fabric is an idea, but you also need flame retardant suspension lines. And the fire canopy, if it’s not designed to just be disposable, is going to be just covered in soot after the first time you use it. So you probably also want something to stuff it into when you’re done using it.

If you really need to keep a small fire going in the rain it’s probably easier to just stick a half-pyramid of aluminum foil over it. Then you don’t need any suspension lines or anything of that ilk. Keeping the tinder and kindling dry when you’re getting started is the important part. A good bed of coals can survive a pretty substantial downpour all by itself. And if the prevailing conditions mean that you can’t get your hands on dry kindling in the first place then you’re probably not having a fire tonight, mini-canopy or not.
(I would further propose that if you are relying on a fire for warmth in your shelter outside of an emergency survival situation you are, in fact, doing it wrong. That’s what your shelter and insulation are for. A fire is nice to have [and those marshmallows ain’t going to toast themselves], but it should by no means be essential to your safety or comfort — especially when rain is in the forecast.)’

And my response: Thank you for your input. I camp out mostly in the e colder months, so I usually have a fire for warmth, but you are right – one should not rely on it. I have been doing this for nearly 60 years. These days I usually use one of my tyvek shelters which embers don’t affect. The ‘fire canopy’ (good term – thank you for that) worked very well in the rain except I had it too low. Most of the wind-driven rain is moderated by the structure of the shelter itself, and the wind is kept away from the fire, and of course the embers blow away from the shelter as well. I had it only about 4′ above the fire, then someone made the fire too large. It needed to be 6-7′ above the fire and the fire needed to be kept small enough so flames never went 4′ into the air. This is actually quite easy to do. I would recommend that others use a fireproof material such as the blankets are made of, or the lighter one I provided the link for (which would weigh about 300 grams). I will have yet another go with the tyvek because I have lots of it and am careful, and just see how I go. I never walk tracks or trails, so I hardly ever toast marshmallows. The track walking brigade probably have little bush sense and should definitely be guided by your advice. I am thinking of this idea mostly for backpacking deer hunters – which is what we were doing in the photographs. Thank you also for the idea about the aluminium foil shelter idea for a small fire. I usually recommend people carry some aluminium foil (though not that much) for roasting fish, but your idea is another good option. Do you mind if I add your comment and my response to my original article?

 

2 Responses

  1. Steve Collins

    What a wanker that guy is, for stating the bleedin’ obvious !
    And, that “someone ” was you Steve, not the apprentice.
    Nicely worded, happy to help out haha.

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