[Stoves] Desktop research topic for someone....Re: Accidental TLUD technique discovery

[Crispin Pemberton-Pigott]

Dear Neil and All

It sounds to me as if the large logs burning slowly towards the and would constitute a migrating pyrolysis front progressing at an angle along the length of the log, all of them at once. 

Thus a gasifier would have to include two conditions, an MPF plus a limited air supply that allowed the gases to be burned at will, at some distance from the gasifying zone.

I suppose all wood burns with an MPF, but that doesn't make every 'fire' a pyrolysing stove. All fires are gas fires (save a few chemical reactions involving metals). That doesn't make them gasifiers. 

I take up the question of the word 'riddling'. In the days of yore when everyone burned coal if the kitchen stove, the grate was not a 'wood grate' as we now prefer to make them, they consisted of individual grate bars that had a square end accessible by opening a door on the front. 

When I was young we heated the house with three coal shoes and the one in the kitchen had this type of bar-grate. When the ash build up was reasonable, a loose handle was slipped over the square end of the bar and they were rotated a little back and forth (not round and round). Each bar was thus 'riddled'. The grate was not shaken as there was no single grate to shake. 

I understood the word 'riddle' to mean the action of shaking the bars individually to bring down the ash. If stones built up they could of course be rotated to drop them. 

Shaking the grate is a different concept from what we consider a wood stove grate being bodily shaken to drop the ash. Such a grate cannot be 'riddled'. 

Is that true? It is very possible the colloquial meaning now extends to shaking the ‎grate. Riddle me this. 

Regards 
Crispin

On 16 Nov 2016 at 16:10, Paul Anderson wrote:

> Anyone,
> 
> Please do some searching about what Crispin describes below. And 
> please share with the Stoves Listserv.
> 
> Paul

Well, I bought an ebook copy of Baden Powell's original 1908 'Scouting 
for Boys', it only took me all evening to then find out how to read the 
**** thing - sorry, mustn't forget:

'A scout smiles and whistles under all difficulties' - an anatomical 
impossibility of course, but I digress:

BP did not know the 'upside down fire', so Crispin's scout leaders didn't 
get it from him!

He describes how to light a pyramid fire, and how to tend a 'star fire' 
which is a 3 stone fire without mention of any stones:

"The »star fire« consists of logs placed like the spokes of a wheel."

and he provides a little drawing

"A great thing for a cooking fire is to get a good pile of red-hot wood 
embers, and if you use three large logs, they should be placed on the 
ground, star-shaped, like the spokes of a wheel, with their ends centred 
in the fire. A fire made in this way need never go out, for as the logs 
burn away you keep pushing them towards the centre of the fire, always 
making fresh red-hot embers there. This makes a fire which gives very 
little flame or smoke."

Interestingly the following link is to a modern 'Scout Manual' which has 
a cover picture of a pyramid fire, but all ablaze so hard to tell how it 
was lit:

http://www.traditionalscouting.co.uk/documents/scout_handbook/The%20Scout%
20Handbook.pdf

In a mini biography of BP it describes how at school......

"....he explored his interest of wood-craft and learned lots of his 
scouting skills. Although officially off limits, he would sneak out into 
the wood surrounding his school where he learned to move silently to 
avoid detection. He also caught and cooked rabbits and other animals, 
being careful not to give his position away with smoke." 

He talks in SFB about using a minimum of wood, and he was aware of how 
American Indians and Zulus amongst other indigenous peoples used fire, 
but his skills don't seem to have extended to the top lit fire.

"The Guide Handbook", late sixties, early 70s has no mention either, just 
the pyramid.

The mystery deepens!

Goodnight, Neil Taylor

P.S. Got the breakfast stove burn right this morning using a half fill of 
damp wood. This really tames and controls the stove nicely, and allows 
for ignoring the stove while eating breakfast, and returning to a nearly 
boiled kettle with good quantity of glowing char for quickly reviving, 
and char to save afterwards. So the damp wood is doing me a favour, not 
merely demonstrating making the best of bad fuel. At the end of the 
batch pyrolysis, and the cooking, I had the stove full of char and 
torrified wood from keeping it generously refuelled. It took quite a 
handful of fresh dry wood without smoking, basically until it was full, 
and brought the kettle almost to the boil by the time I returned to it. 
The stove never choked with ash, keeping a good primary air flow and I 
didn't need to riddle (shake) it.

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