Fire Building Club

[Spiderman]

Originally Posted by SoulKiss

Happy to go with a bigger size, just that its more work, even a fire in a half a petrol drum is plenty to get about 40 people around (and as most of the heat from them goes straight up.....)

I have a half barrel BBQ and tbh you can get about 6 - 8 standing peeps round that comfortably. 40 SK? How big is your barrel? lol

I think we can judge this better when on site, its all pretty accedemic right now.

As for the heat, i was watching a survival programme and a certain Mr Ray Mears suggests that a "parralel logs" fire is the best to produce heat and keep the flames low.

I'm like Dan above, if it was my fire it would be exactly as he bescribes... thats what i used to build on beaches when i lived abroad, whether it was for a full on full moon party or just me and my girl to chill by. Either way, there was LOTS of heat and LOTS of flame.

not a good idea near tents, as has been said.

[mr.anderson]

OK, so lets do the maths on this one:

Assmuning that the average person standing facing the fire is 1&1/2 ft wide plus an extra 6 inches to allow for the beer in one hand stance = 2ft space per person.

Allowing for a comfortable standing distance from the fire of 1 metre (3 or so ft):

6ft round fire: (6 + 3 +3) * 3.14 = 37.68ft. Based on the assumptions above, this allows for 15 people holding a beer in one hand and 3 holding a beer in each hand.

4ft by 8ft rectangle: 2 * ((4 + 3) + (8 +3)) = 36ft. Based on the assumptions above, this allows for 18 people holing 1 beer in one hand.

Now, in terms of effort:

The 6ft circle will require a moving of 28.64 square feet of earth 1ft deep.

The trench will require the moving of 32 square feet of earth 1ft deep.

In terms of beers in hand per square foot of earth to be moved:

Circle = 73.32% efficiency
Trench = 56.25% efficiency

[Stu]

1ft deep sounds like overkill just to protect the turf
But you seem to have things in hand.

[SoulKiss]

Originally Posted by Stu

1ft deep sounds like overkill just to protect the turf
But you seem to have things in hand.

It IS overkill, it probably wont go quite that deep, will depend somewhat on the weather, and when I first put that figure in I hadn't thought of the leave a foot's gap from the edge of the cut turf to the fire.

[Stu]

I also don't get why you need a liner under the fire before the soil? although the rocks round the edge are a good idea to contain it.
If the idea is to go down a week before to dig the pit I would worry about the condition of the turf, and the turf under the turf when you dig out the turf and lay it on top of other turf

[SoulKiss]

Originally Posted by Stu

I also don't get why you need a liner under the fire before the soil? although the rocks round the edge are a good idea to contain it.
If the idea is to go down a week before to dig the pit I would worry about the condition of the turf, and the turf under the turf when you dig out the turf and lay it on top of other turf

The liner is to put the removed turf on well away from the fire - can load it up next to the pit then drag it away...

[Stu]

[Spiderman]

Originally Posted by mr.anderson

OK, so lets do the maths on this one:

Assmuning that the average person standing facing the fire is 1&1/2 ft wide plus an extra 6 inches to allow for the beer in one hand stance = 2ft space per person.

Allowing for a comfortable standing distance from the fire of 1 metre (3 or so ft):

6ft round fire: (6 + 3 +3) * 3.14 = 37.68ft. Based on the assumptions above, this allows for 15 people holding a beer in one hand and 3 holding a beer in each hand.

4ft by 8ft rectangle: 2 * ((4 + 3) + (8 +3)) = 36ft. Based on the assumptions above, this allows for 18 people holing 1 beer in one hand.

Now, in terms of effort:

The 6ft circle will require a moving of 28.64 square feet of earth 1ft deep.

The trench will require the moving of 32 square feet of earth 1ft deep.

In terms of beers in hand per square foot of earth to be moved:

Circle = 73.32% efficiency
Trench = 56.25% efficiency

That is one quality post, Sir! And it proves my circle superior too, yay!

[SoulKiss]

Originally Posted by Spiderman

That is one quality post, Sir! And it proves my circle superior too, yay!

Cant fault the maths at all - however, the concentration of fire is also a key element.

In the round configuration, the density of the fire is greater, creating a hotter fire, consuming more fuel.

The trench fire creates a gathering point that is more efficient, and not really needed as a heat source.

2xtelegraph poles lying sideby side with a starter fire made on top that is allowed to ignite said poles will burn for ages with little attention or drama.

TBH its all hypothetical anyway, I'll rock up on the day and sort it out

[ophic]

hmmm a circle has the shortest perimeter for its area. So a stretched out design of equal area to the circle proposed, should be the most efficient