From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Portable propane campfire?
Date: Sun, 14 Oct 2007 21:48:21 -0400
Message-ID: <v3g5h3pb9kt50q4igvtds968e9s279bdrv@4ax.com>

On Sun, 14 Oct 2007 14:25:51 -0700, "Tom T" <tominkirkland@gmail.com> wrote:

>Neon John wrote:
>
>> I don't own one but I've been around similar products.  Might want to
>> look at the FAQ
>>
>> http://www.propane-campfire.com/Propane_Campfire_FAQs.html
>>
>> 18,500 BTU isn't much.  It'll probably look pretty but I'd not expect
>> much heat.  And at a claimed 18 hours per 20 lb tank, I'd want to
>> have a ready supply of propane at hand.
>>
>> John
>
>Thanks John.  The BTU output is a concern as I do want it as an outside
>heat source too, just like a campfire. Question is, how many BTU can a
>20lb tank practically deliver at once anyway?

I hit on this table:

http://www.nwes.com/propane_info.htm

By googling "propane BTU per pound" (go figure :-).  21,548 BTU per pound or 430,960
per 20 lb tank.  At 18,500 BTU/hour input, the duration would be 21548/18500 * 20lbs
= 23 hours.

The withdrawal rate is thermally limited.  After a certain rate, more heat is
extracted by the vaporization of the propane than can conduct/radiate into the tank.
The tank frosts, the frost makes good insulation, the tank frosts more until at some
point the propane gets so cold that practically none escapes.

The withdrawal rate at which that happens is dependent on a lot of factors - the
initial temperature of the tank, the tank's color, what heat sources are in contact
with the tank, etc.

I know that a 100,000 BTU burner will frost a 20 lb tank before it's half empty. I've
been known to float a tank in a tub of warm water to forestall the frosting when
running a large burner like that.

That 18.5Kbtu fireplace shouldn't cause any frosting problems but then again, it
won't kick out much heat either.

I found this spec for hickory wood:

http://aggie-horticulture.tamu.edu/carya/species/ecobot.htm

"Hickory wood is very dense, weighing about 4600 lbs. per cord and producing about 25
million BTUs per cord when burned."

25E6/4600 = 5435 BTU per pound.  A stick of firewood on my pile weighs about 5 lbs.
Stack up 6 of those and the available heat is 5435 * 5 * 6 = 163,043 BTU.  If that
wood burns up in 3 hours, the release rate is 163043/3 = 54,347 BTU/hr.  If it burns
up in 2 hours, 163043/2 = 81,521 BTU/hr.

Thus we see that a small fire using 6 sticks of hickory puts out more than twice as
much heat as the propane heater.  Especially once the fire had developed glowing
coals, much of the heat is radiant heat that warms whatever it strikes. Most of that
propane fire's heat will be dissipated in combustion gases that rise without heating
the surroundings.  Only if the ceramic logs got bright red hot (like a ceramic
surface burner heater) would significant radiant (warming) heat be released.

If you don't need the flickering flames and only want to be warm outside then I
recommend one of these:

http://www.reverberay.com/products/pt.html

I have two of the small ones and one of the large ones.  I love 'em.  I frequently
carry a small one with me on camping trips.  Essentially all the heat is released as
radiant heat.  It can warm a whole campsite.

My local NAPA sells the small heater for about $100 and the large one for about $149.

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Portable propane campfire?
Date: Sun, 14 Oct 2007 23:56:02 -0400
Message-ID: <h2o5h3tnckqbi6b40q2n10edhsmqctspci@4ax.com>

On Sun, 14 Oct 2007 19:25:53 -0700, "Tom T" <tominkirkland@gmail.com> wrote:

>Neon John wrote:
>> On Sun, 14 Oct 2007 14:25:51 -0700, "Tom T" <tominkirkland@gmail.com>
>
>> I hit on this table:
>>
>> http://www.nwes.com/propane_info.htm
>>
>
>> I found this spec for hickory wood:
>>
>> http://aggie-horticulture.tamu.edu/carya/species/ecobot.htm

>John, you never cease to amaze me with your technical input.
>
>I'd bet dollars to doughnuts this the best heat output comparison done
>regarding campfire with wood compared  to propane.

You're welcome and thank you.  That's one of those calculations that I'd always
intended to throw a round tuit at but never did.  Satisfied my curiosity too.

Speaking of fires, the last few nights have been gloriously cool enough to permit
building fires in my fireplace, albeit with the doors and windows open :-)

Having sold my fire starter to a fellow camper who wanted it a lot more than I did

http://www.neon-john.com/RV/Propane/Lighter_index.htm

I was looking around for another zero cost, zero hassle method of starting a fire.  I
don't get a newspaper so that was out.  I've tried two experiments that were both
highly successful.  Both involve used fryer fat.

I use a 50-50 mix of lard and Crisco shortening in my fryer.  The taste it gives
french fries is just out of this world.  I discovered by accident that a container of
the used fat makes an excellent zero cost hairball remedy for my kitties

http://www.neon-john.com/pets_home.htm

Since I served BBQ and fries out of my weenie wagon all summer, I collected a
considerable amount of fat.  I needed new uses for the stuff.  Fire starting is it.

The first experiment involves placing about a tablespoon full of fat in the center of
a sheet of ordinary laser printer paper, then wadding it up, making sure that the
grease spreads all over the paper.  Sit the ball on a little pile of ashes, light an
edge and pile up the fire wood.  A significant blaze burned for 7 minutes, more than
long enough to get the main fire going.  The grease burned at a lower flame for
several more minutes.  The ashes soak up what grease melts and runs from the paper,
keeping the fire going after the paper is consumed.

The second experiment involves charcoal.  Just before changing out a batch of fryer
oil, I filled both fry baskets with briquettes.  I let 'em "fry" until all the
bubbling stopped, then lifted them out.  As the surface got dull, indicating the
grease had all soaked up, I gave 'em another brief dip.  Let 'em cool and place in a
1 lb coffee tin or something similar for storage.

One briquette laid on a little pile of ashes does the trick.  Light the edge of the
briquette and pile on the wood.  I didn't time the burn but it was more than enough
to get the fire going.

Of course, lighter fluid, kerosene or any of a number of substances would have worked
but I was going for the zero cost option.  A charcoal briquette isn't quite zero cost
but it's close.  The paper wad version works so well that it will be my choice here
in the cabin.  The briquettes will probably go in the MH.

I just sat back down from lighting a fire to write this.  I have three kids, er,
kitties laid out in front of the fire like cordwood.  Life is good :-)

John

From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: Colorful campfire?
Date: Fri, 25 May 2001 22:50:06 -0400

John Gray wrote:

> "Neon John" <johngdDONTYOUDARE@bellsouth.net> wrote in message
> news:3B0D3E55.C0534D0A@bellsouth.net...
>
> > Bill Davis wrote:
> > >
> > > Dynamite works...
> >
> > Nah, it just burns unless you strap several sticks together.  Now
> > tossing a box full of gun cartridges in the fire, that's FUN!
>
> Let's not forget batteries and aerosol cans... always good for some
> excitement!

The safety nazis have pretty much engineered the fun out of aerosol
cans.  They now just rupture and spew instead of blowing the end off
and rocketing through space trailing a fiery tail of burning
contents.  Damn!  A can of starting ether still makes a pretty good
fireball but nothing like the old days.  Duracell batteries make a
pretty good pop if you make a small addition.  When they reversed
the chemistry a few years ago so that the shell became positive,
they also included a nylon seal on the center electrode.
Unfortunately this seal doesn't hold pressure too well.  I shot some
AAs recently and found that the center electrode just goes "poof".
The addition is to tie a couple of hunks of iron wire around the
long axis of the battery like you were tying ribbon around a gift
package.  If twisted very tightly, the wire will hold until the rest
of the battery can do its thing.

Another interesting thing to do if the fire is large and isolated is
to toss in a water pipe bomb.  Just make a pipe bomb with a 6" long
hunk of 2" black iron pipe and a couple of caps, only fill it to the
top with water instead of gunpowder.  seal the threads with high
temperature nickel bearing pipe dope and toss in the fire.  Then run
like hell!!!  Usually the resistance welded seam will rupture but
sometimes it holds until there is complete structural failure of the
pipe.  Spectacular!  Of course, everyone must be a hundred yards or
so away cuz the shrapnel is really moving.....

bone to the safety nazis:  If you actually do this, you will die.

John