[Stoves] stoves and credits again

neiltm at uwclub.net neiltm at uwclub.net
Sat Sep 30 10:52:29 CDT 2017


On 30 Sep 2017 at 12:56, Crispin Pemberton-Pigott wrote:

> 
> >To me, the burning of charcoal as charcoal (not during the migratory
> pyrolytic front stage) inside a TLUD stove is to be avoided.
> 
> That is OK, in terms of an opinion, but it is not what people are doing
> and I expect the main reason is fuel efficiency.

It always surprises me that no one ever mentions that the char burning 
stage may be almost perfect for simmering something after bringing it to 
the boil.  Porridge for eg. (5 mins simmer).  Peas,10 mins, potatoes 15 
to 20 mins.  Given the difficulty with turn down with most TLUDS, the 
char stage if long enough, and hot enough, can potentially be anticipated 
as a specific cooking task and fuelled accordingly, and that is what I 
try to do.

Crispin's mention of the primary air being controlled by the choice of 
fuel such as pistachio shells, matches my experience and how I use my 
simple Chinese ebay NDTLUD stoves.

If I utilise fairly fine woodchip I can obtain a vigorous enough burn, 
but then refuelling is useless if confined to the very end of pyrolysis 
as there is too much inert char above, and a smoky mess results. If I 
want to extend such a batch loading I need to slowly introduce a chunk at 
a time in the later half of the pyrolysis so that there is some top fire 
by the time the P front reaches the bottom. If I use decent sized chunks 
throughout for maximum primary airflow then the char stage is so vigorous 
and close to the surface that feeding additional fuel is easy and smoke 
free, and the stove can be sustained indefinitely with occasional ash 
riddling.  However I use the stove there is always some useful char at 
the end of pyrolysis if I want it, which mostly I do for the BBQ which 
has been sustained entirely by the stoves and the occasional camp fire 
ever since our first Reed SL stove over 10 years ago.

Certainly the Reed XL stove, with its cleaner burn and more restricted 
primary air is the best char producer, and emptying into my biscuit tin 
'quencher' I am often surprised by the apparent lack of much if any ash.

My burn chamber burned out on the XL, but it burned out at the level of 
the secondary air holes, 'tearing along the dotted line' so to speak.  
The bottom half was fine, whereas someone shared a picture with me of 
theirs and it had burned out at the bottom, not the top, so clearly we 
were using our stoves significantly differently.

I appreciate Paul's point about burning char in a TLUD subjecting the 
firebox to higher temperatures shortening its life, but I haven't worried 
too much with the cheap Chinese stoves and so far have not seen much sign 
of them burning out, and they have had a lot of use by now.  Besides, I'm 
not giving up making toast over the char after making the coffee!  I can 
always chuck a tin lid with holes bodged in it into the bottom of a 
burned out pot.  Then there is flipping the pot support off and perching 
the kelly kettle on what's left after cooking a meal and adding a few 
long vertical sticks if necessary, as such an easy way to boil a kettle 
for coffee and then washing up, that I shall never care what other 
people's rules might be on that, LOL!  

IMO the 'excess' primary air NDTLUDs make the TLUD extremely versatile as 
discussed above, because of the very generous primary air, in a way that 
the very restricted primary air stoves like the Reed stoves cannot be and 
as mostly discussed here. 1 to 6 ratio is it? This is at the expense 
however of soot on the pans and an eye stinging burn, but that probably 
only puts it on a par with a rocket stove.  Living with it, as my only 
stove for a month in variable weather car camping/touring, a good strong 
usable and sustainable fire with often less than ideal damper fuel is the 
number one priority and I can hope to keep upwind of the emissions.  
Works for me :-)

Neil Taylor




More information about the Stoves mailing list