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Turk
2006-02-12, 15:13
Okay guys, this might be totally off the mark, but let me
know what you think. I recently watched a Jon Hood survival
video and, I was looking at possibly getting a Maccat tarp when
this possibility sprang to mind. I'm not saying this is something
you would do all the time. Certainly not in areas that you are
worried about enviro impact or Leave No Trace. Maybe in a
worst case, freezing your butt off scenario. Or deep backcountry.
Basically I would like to hear your opinions on if you think it
would even work? And any thoughts on how well?

http://www.geocities.com/ekontario/hammock_rock_insulator.JPG

The principal being you clear away, or dig a rectangular area under your
hammock and tarp to avoid combustion hazards. Using rocks heated from
your campfire, including the rocks forming the fire ring itself. Stack the
rocks under you, before extinguishing the fire for the night, and you
should get some nice toasty convection currents under you to add
warmth.

I haven't tried this yet, but I plan to. I have absolutely no idea
how effective this will be. My guess is minimal. Perhaps 2-4 deg
warmth for no more than 4 hrs. I think I read somewhere that certain
rocks retain heat better eg: sandstone, slate. But the trade off is
these more porous rocks can explode if rapidly heated and cooled.
I've seen them crack ... never explode. Anyways I don't know
how well this will work, but will try it. In survival manuals they talk
about having hot rocks against your clothing. Rocks from my average
fire would burn through clothing quickly. Then again, if my hammock
is suspended 12" above, I could be loosing alot of the available heat.

Thoughts?

(p.s. - this can't be any more rediculous than my tight-wire act last
year trying to make the "high-hammock" pitch work from the garage
rafters. ... hopefully not as comical )

Salvelinus
2006-02-12, 15:44
Thoughts?

Only one: I'd want to be DAMN sure my knots were tied right!

peter_pan
2006-02-12, 18:28
[

Thoughts?

(p.s. - this can't be any more rediculous than my tight-wire act last
year trying to make the "high-hammock" pitch work from the garage
rafters. ... hopefully not as comical )[/QUOTE]

Yes it can.... what about LNT and your ton of fire scared rocks...since I know that you are not heating them with an alcohol stove :biggrin: ....not to mention the size of the fire to heat that many rocks....

BTW I'm reminded that all this rock gathering is heavy and time consuming...it is easier to do this near a river ...but way more dangerous, as may rocks like quartzite river cobbles can and do explode when heated....

Recommend that you try a different approach.

Pan

dropkick
2006-02-12, 20:23
I would go with the fire in front reflector behind setup instead. Safer, easier, and I'd bet it keeps the heat up longer.
http://www.freeimghosting.com/images/dropkick/p1139789649352.jpg
If you really want to go overboard you could build the fire in front of a rootball, bank, or a big rock so it reflects the heat into your reflector.

Mutinousdoug
2006-02-12, 22:06
Dig your hole. Build a fire in it and let it burn down to coals. Scoop the coals out (with your kukri?) and then pitch your hammock over the now empty hole.

No rocks to carry around, unless you want to put a couple in to step on when you get in and out.

You are going to look like a chimney sweep when you get back from your trip either way.

As for heating rocks, I've had one I was using in a fire-ring pop smartly enough to spatter my face and make me glad I was wearing glasses.

KLeth
2006-02-13, 01:36
The Sami people slept on fire.
It was done by making a fire, then after it had burned down, the live coal were spread and covered with bundles of brushwood. The bundles then where covered with reindeer pelts on which the sami slept. The trick is, not to have too much air flow or you will burst into flames but yet so much air that you won't get carbonmonoxide poisoning.

I guess a bit of the old ways could be used. Maybe by making a trench, filling it with live coals and covering it with ashes, gravel, turf and or rocks - This should last a bit longer than just hot rocks.

Just an idea for hammock-roasting :biggrin:

KLeth
2006-02-13, 01:42
As for heating rocks, I've had one I was using in a fire-ring pop smartly enough to spatter my face and make me glad I was wearing glasses.
Was it flint stone ? - Flint stone can crack or explode and are quite dangerous to combine with fire. We always check to see if there are "composite-stones" or flint in firerings before we use them. Other types stones might also crack.

I'm glad you were wearing glasses.

Mutinousdoug
2006-02-13, 10:25
Was it flint stone ? - Flint stone can crack or explode and are quite dangerous to combine with fire. We always check to see if there are "composite-stones" or flint in firerings before we use them. Other types stones might also crack.

I'm glad you were wearing glasses.

As I recall, it ws fractured granite and it wasn't pulled from below waterline although these rocks spend probably 6 months of the year covered in snow.

Seeker
2006-02-13, 11:05
i'm assuming you're in a 'survival' situation, whatever that means, and LNT is out the window... i still think dropkick's idea of a reflector would be easier and more efficient... old timers used this 'trick' all the time, and the baker tent, and others, were made to take advantage of the reflecting technique. Horace Kephart talks about laying in a lean-to in front of a fire during the winter in his camping and woodcraft books... it's a proven technique, and i'd say a lot easier than digging up rocks... so i'd say, no, don't use rocks with a hammock.

sleeping on the site of the fire, to absorb the heat from the ground, or burying rocks, smoothing the ground over them, and sleeping on top, on a foam pad, in winter, without a hammock, makes sense... i used to claim the spot over the transmission on the back deck of my M-1 tank because it was the warmest... you HAD to have a foam pad under you, or you'd burn yourself...

when i was in boy scouts, we had a rock explode... most of it went straight up in the air, it seemed, as the only one hit was our patrol leader... some stone fragments got him in the eye, and we had to evac him right away... he was ok, but a stone fragment did embed itself in his eye, and another piece scratched his cornea... never did find out what kind of rock it was... we used to have some granite rocks at my parents camp for use in the winter... you'd set them on the stovetop (wood stove) before bedtime for an hour or so, then wrap them in a rag and leave them at the foot of the bed to keep your toes warm...

KLeth
2006-02-13, 11:57
The reflector could be of alu-coated mylar. Would also aid in sheltering against weather.
I guess that the fire should be a slow burning fire, like a two-log fire.

Lanthar
2006-02-13, 12:26
ditto on the refletor... way better, you're directly using the heat and way safer... easier to 'stoke' as well (though that does require getting out of your hammock (unless you want to play chuck the log and hope you don't wreck your reflector...

Turk
2006-02-13, 14:13
Thanks for all the good advice.

hope I didn't upset anyone to whom Leave No Trace concepts are
very personal.

Perhaps this is more fitting to another thread, but it is very difficult for me
to imagine where LNT HAS to be enforced. In north Can, you use
old campsites and traces of old campfires to confirm your
course, and bolster your confidence. There's just such expanses of
wilderness where literally you can head in any direction but south and
never cross a road, never see a power line, or any hint of humanity.
Trails more often than not are not "tangible paths", but rather a
proposed route on a map. Signs of a camp tell you you aren't lost.
The reality is no towns, no roads, no people.. over an area 1/2 the size
of the continental United States. Anyways ... I hope that kind of helps
share my perspective.

I truly respect Leave No Trace concepts, and quite honestly since
I found this forum, I have made much greater effort towards LNT. Most
importantly though, I would never practice the same style of hiking if I
was in your country, or any with heavy hiker traffic where LNT is a serious
issue. Didn't want you to think I was an enviromental $#!*-head. Have
the utmost respect for what you guys practice. Kind of wanted to clear
that up in case anyone was ready to crucify me.

Thanks for the words of caution about exploding rocks. I am definately
going to have to do some homework on this one.

Dropkick - thanks for the reflector idea. Think it has major potential,
except that I have to be careful what type of wood I am burning. I burn
alot of pines and cedar which really throw the sparks especially when
the coal bed starts cooling. - otherwise Mutinous raises a good idea.
The risk with coals under me though is too great.

- always have easy access to rocks .. and ya ... my
fires tend to be a bit large. I really have gone more conservative
though over the last year. I would commonly burn about
2-3ft x 6-7ft firepits and use around 2-3 chords of wood per night. I cook
on alot smaller now and limit the larger ones to cold nights. I used larger
fires more for the ease of firewood gathering. You can just feed a pile of
whole trees into your pit rather than doing alot of cutting and chopping.
The light and heat they provide let me stretch out my night activity
alot longer.

Seeker
2006-02-13, 14:48
wow... them's some big fires... i quit carrying a saw and hatchet once i realized i could make a suitable cookfire out of branches no larger than my thumb... in a hardwood bottom, there is already a ton of stuff laying around that you can break with your hands... no need to even lean anything against a tree to kick with your leg/foot... just pick it up and break it into small pieces by hand... fire ring is about 24''-30'' across, with the ash pile never really exceeding 18''...

but then, i live pretty far south, and don't need it for much heat...

Turk
2006-02-14, 01:16
Before I end up making a "how to evacuate a burning hammock" video,
or get hit by my rock pit of frag- grenades ... I'll just stop being a
cheap skate and cough up the bucks for a JRB Nest. Emailed Pan
tonight for shipping costs.

In the long run I'll be alot happier and safer im sure. Whats a few hundred
more bucks in the grand scheme of my gear.:biggrin:
Besides everyone raves about them, and I'm sick freezing my henie off
pad surfing. Just gotta figure out how I am going wedge another 7"
cube into my kayak stern.

dropkick
2006-02-14, 03:58
I don't know diddley about kayaking, but I saw a kayak once with some stick on hooks attached to the stern. Didn't see them used, but the only thought I came up with for them being there was to tie down a small dry bag. Don't know if that's a good idea or not.

Seeker
2006-02-14, 10:51
turk,

curious timing on all this... i got a book out of the library saturday called 'primitive outdoor skills' or some such... the chapter i read last night was about making a heated bed... something about trenches covered with rock slabs, with a fire pit at one end, buried in the ground. the smoke and heat hit an overhanging lip and are deflected into the trenches, and come out a mud chimney at the head of the 'bed'...

quilt's still easier... you need to get a bigger kayak... (i know... simplistic...)

i went kayak camping once, as a scout, back around 1978... it was wonderful... i still canoe camp once in awhile, but the kayak was a lot better. can't carry as much, but it was lighter, i could paddle all day, even as a kid, and was just a lot more fun...

good luck with the extra cubage...

dougmeredith
2006-02-14, 12:00
Others have alluded to this, but in a survival situation, you might choose to go to ground with a fire bed:

http://www.survival.com/art1.htm

I have never tried this.

Doug

dropkick
2006-02-17, 02:00
All this reminded me of an old basic tent stove idea:
http://www.freeimghosting.com/images/dropkick/p1140155696332.jpg

incognito
2006-02-17, 23:18
[quote]- always have easy access to rocks .. and ya ... my
fires tend to be a bit large. I really have gone more conservative
though over the last year. I would commonly burn about
2-3ft x 6-7ft firepits and use around 2-3 chords of wood per night. I cook
on alot smaller now and limit the larger ones to cold nights. I used larger
fires more for the ease of firewood gathering. You can just feed a pile of
whole trees into your pit rather than doing alot of cutting and chopping.
The light and heat they provide let me stretch out my night activity
alot longer.[quote}

Thank You Turk for this CLASSIC information!!!!!!! :biggrin:

Have you been camping along the AP trail? They say fire wood is hard to come by :biggrin:

Nice campfires Turk, backoff a little, save some for the next guy :biggrin:

dropkick
2006-02-18, 02:46
[quote]- always have easy access to rocks .. and ya ... my
fires tend to be a bit large. I really have gone more conservative
though over the last year. I would commonly burn about
2-3ft x 6-7ft firepits and use around 2-3 chords of wood per night. I cook
on alot smaller now and limit the larger ones to cold nights. I used larger
fires more for the ease of firewood gathering. You can just feed a pile of
whole trees into your pit rather than doing alot of cutting and chopping.
The light and heat they provide let me stretch out my night activity
alot longer.[quote}

Thank You Turk for this CLASSIC information!!!!!!! :biggrin:

Have you been camping along the AP trail? They say fire wood is hard to come by :biggrin:

Nice campfires Turk, backoff a little, save some for the next guy :biggrin:

Your just kidding but you have to remember Turk is from the untrammeled north. By having a big fire he could actually be doing the forest and others a service as he is getting rid of some of the deadwood build up.

Those of you from the more traveled areas may not know this, but we actually pay people to clean the deadwood out of some areas, or have controlled burns to get rid of it. The deadwood gets to built up and causes a fire hazard, and also it chokes out the small plants on the forest floor and can lead to an unhealthy stand of trees.

On the other hand I don't think Turk is actually burning 2 to 3 cords of wood a night. I used to heat my house on 3 cords for an entire winter, and I kept it warm.
A cord measures 8' x 8' x 4'

Iceman
2006-02-18, 20:37
I am thinking Turk does enjoy an occasional BonFire. So do I. Out here in the Pacific Northwest fire wood is plentiful. I have burned huge piles of wood. Once each year during our elk season, we have a ceremonial burn, which can probably be seen from space, sheep leggins, spirits, you get the picture. Global warming, now you know why.

dropkick
2006-02-19, 03:04
I think you've moved away from bonfire and into conflagration.
You know it's too big when a guy with a pitchfork and horns comes by and asks if you can tone it down a bit because it's making it to hot where he lives.

Turk
2006-02-19, 17:26
On the other hand I don't think Turk is actually burning 2 to 3 cords of wood a night. I used to heat my house on 3 cords for an entire winter, and I kept it warm.
A cord measures 8' x 8' x 4'

Hmm my apologies on that one. I was actually not trying to
exagerate that much. But I was under the assumption that a cord of
wood measured 2ft wide,8ft long, 4ft high. My rough numbers there
I thought represented about 8 12ft dead cedars. We get alot cedar
trees around that height that die of a certain parasite. Wish I could
remember the name off the top of my head. But anyways... moral
of the story .... fire way too big. Without embarassing myself too
much, I'll tip-toe lightly around why I really often needed a fire of
that size. Suffice to say .... novice whitewater experience, average
underfunded teenagers, lack of waterproofing. Nuff said.
For about 4 years these were "Laundry drying fires". On a good hot
coal bed you can throw soaking wet cedar trees on and get some
good billowing smoke to dry out even a 5 man tent
:biggrin:

dropkick
2006-02-19, 18:47
OOPS!! I'm looking at your post of my post and it bothered me, something was wrong, couldn't figure it out what it was for a minute, and then I got it.

A cord is 8'x4'x4'

Fills the back of a truck.
:damnmate: