Norfolk build

[rokdok]

Hi Chas, This is a very interesting build. You have worked remarkably quickly . I have to say I'm with Dave and JMS on the insulation front , but I can see your point about only wanting to make pizzas and to be frank most of the precast pizza ovens don't have much insulation either.
It may well be that you will have sufficient heat retention to cook in the oven immediately after your pizza fest, should you want to , and you have also left yourself a bit of margin to put a little insulation on the dome if needed.
I'm following with interest - all the best RD

[chas]

Cheers RD, I'm focussed on a weekend bake:

To maintain progress and gain info, today's test burn had to take place in drizzle:



There was a degree of inevitability about what happened next: I knocked up some pizza dough and spent a happy hour under the brolly gradually cranking up the temperature, half expecting to hear the dome tearing itself apart. When a dull sort of twang happened, it turned out to be the chimney - cracked from top to bottom. Anyway, I pressed on to a full hour of burn (though not a really full-on burn) and slung some dough with a smear of chopped tomato, salt and a drizzle of olive oil into a swept valley between the embers. The thermometer read 185C on the floor.



Half an hour later I dragged this out, and surprisingly good it was too... eaten with balsamic and salt in a puddle of olive oil.



So, I continue to be hopeful I can up the temperature to the 200+ I want and as I say, have this weekend lined up as the real test after a couple more daily 'hardening' firings.

By the time I took the feast out, the outside top of the dome was hand-hot, so heat loss lags by quite a bit. I may just get away with it...

Chas

[cobblerdave]

G'day
Bummer to hear about the crack. Ovens crack and clay and earth ovens are the worst for it . But they seem to survive them to cook on.
One good thing is that the clay will easy to clean of the brick if you should ever want to rebuild your oven.
But what the heck, cook on. Enjoy your cooking
regards Dave

[chas]

Cheers Dave, but my mistake for saying chimney when I meant chimneypot - it was the bit of salt-glazed drainpipe that cracked, not the brickwork or clay bonding. It's functional for the moment.

Today I though I'd make the fifth 'hardening-off' firing as close as prudently possible to a "real" fire - ie while keeping to small bright fires often restocked rather than a full-on burn, I'd keep it going for a couple of hours, have the door open for at least 15 mins 'working time' and then leave it shut for an hour, just to see what it could offer.

I started off with an 'upside down' fire at the doorway, under the chimney and lit with the plumbing blowtorch. It lit easily, burned down really well, then I pushed it into the middle and carried on with regular stokings of small timber.

After 90mins of careful firing, mainly door shut, it was reading 375, the fire was just smouldering ashes and I got the fire going again for the last half hour. By the time I'd done that it had dropped to just under 300. It loses a lot of heat with the door open. It's a bit boring with the door closed.

At 2 hours it was back up to 350deg, I let the flames die down a bit and at 2hrs 15 minutes pushed the ashes to each side. The thermo had been reading 320ish but rose to 330 as I put it the middle of the cleared floor.
With the door open for a total 30 minutes (time for a pizza or three?) it was showing 225 with no visible fire. I shut the door, put the cap on the chimney. An hour later when I opened up it was still 200C.

1) I'm thinking I will get away with it, but also see the sense in getting out the old Devil's Porridge...

2) if I did DP it, I wonder how much longer I'd keep that good cooking temperature

3) really, really, don't want to tempt fate, but the chimneypot crack is the only 'damage' so far.

4) memo to self: get going quickly and I'll be starting at nearer 350 than 330, and with flames

A bigger fire tomorrow, then Sunday it's 'go for it' time, and despite claiming I'm only interested in it for pizza, can't resist the thought of bunging a full kilo loaf in there afterwards as an experiment.

Chas

[cobblerdave]

G'day
To cook pizza continuously you put you fire and coals to one side. Keep 6 or 8 sticks of wood in the entrance way, preheated. Throw the sticks on the coals and you'll get instant flame rolling up the walls. This reflected heat cooks the tops of your pizza and replenishes the heat in the floor. The floor temp will drop off as it's shielded by pizza, swap the fire over to the other side and continue.
I've cooked pizza for 40 people this way, how many I couldn't count, but they will cook faster than you can make them.
Regards dave

[chas]

Hi Dave, and thanks for your continuing support and for sharing experience - it would have taken me ages to have thought of that refinement to the process, if I ever did.

I'll practise in the last test fire today!

Chas

[rokdok]

Sound advice Dave, good luck today Chas- I'll check back later to see how you're getting on . RD

[chas]

So, the last of a week's test burns... modified to pretty well full chat: larger fire (lit top down again, in entrance under flue initially, then pushed into the middle) added to three of four times. After just one hour of burn it was reading 350C on the floor... I wondered whether it was too early to start a bake, whether there would be enough heat absorbed to sustain it, but as this is still an experiment and any pizza a bonus I pushed everything to one side, swept clean, slid in some test dough and added small wood to the embers to get flame.






It only took three minutes to do all that but when I replaced the thermometer it was only showing about 280C. With the door open in 'pizza-cooking mode' - and despite the lively fire - the temperature dropped steadily so that after 15 mins cooking it was nearer 200. Pizza was removed - cooked - embers moved across and the thermometer replaced in the new cooking position - it recovered to 240 before I shut the door. If I'd wanted to cook another, I reckon it would have been ok.

With door and flue shut, after 1 hour it was still showing 220C
At 1 hour 30mins it was a gnat's under 200.

I reckon anything like today's 240 to 200 over 90 minutes should produce a loaf - I normally start (electric fan oven) with 240 for 10/15 mins then 200 for about 30.

New things learned:

1) moving the fire from side to side gives you a chance to start over, as per Dave
2) with live fire one side, it's probably better to turn the pizza to get an even browning down the sides, and better to have an elongated shape to make the most of it.
3) with an elongated shape, you can have a narrower, rectangular peel and it's maybe more manouverable. I don't have a peel, I used a well-floured baking tray. If the present Mrs Chas isn't watching, I'll be cutting it down and fitting a handle tomorrow...
4) I really must fit a handle to the brush too - reaching right in to sweep and your knuckles close to the fire is a test of resolve


It's irresistible: I'll run with an hour's burn tomorrow and go for the double, plus one of my usual kilo loaves to follow.

Chas


ps Air temperature at the end was 12C.

[cobblerdave]

G'day Chaz
Your ovens still damp. The pics show carbon still on the walls and smoke is still in the oven. In a dry oven the carbon burns of the wall and you can see clean brick. In a dry oven you mainly only have smoke at start up the heat burns everything cleanly before it gets a change to go up the chimney.
At the moment your fires have there energy used to turn that remaining moisture into steam. Don't ramp the fires up bigger you'll only crack your oven. Keep them to the one size and you'll find that the temps will naturally go up as the oven dries. Letting the oven cool is good as that moisture deep in the brick has a chance to migrate to the dryer surfaces so you fires are more effective to remove it.
It takes about an hour and 1/2 to get a dry oven to temp for pizza . And that's any size oven , small ovens have room for small fires big ovens have room for big fires!. Pizza temp is 400C to 500C. Yep that hot. For the moment if you want to get that pizza to really pop. Pick it up with you pizza peal and hold it closer to the oven ceiling and it will crisp up real fast.
I use a flat homemade aluminium rake to move the fire around. You can use your metal pizza peal as a shovel. I don't bother with brushes any more in a burning oven. They don't last long and I definitly don't like metal as if any bristles should fall off and get in the food , I'd hate to think what damage that would cause. After scrapping the fire and ash to one side I just use the flat of the metal peel and slap it on the floor. The dust rises and the heat takes it out the chimney do that a couple of times and it's done.
The shape of the pizza has a lot of bearing on the taste.. I personally do not trust a round pizza .... It's probably store bought.
Regards dave
Regards dave

[chas]

Nov 1, 2014 22:03:24 GMT cobblerdave said:

G'day Chaz
Your ovens still damp. The pics show carbon still on the walls and smoke is still in the oven. In a dry oven the carbon burns of the wall and you can see clean brick. In a dry oven you mainly only have smoke at start up the heat burns everything cleanly before it gets a change to go up the chimney.

Hi Dave, you may be right and I'll take note not to really 'go for it' in firings just now - but could the carbon sootiness and smoke be because I use wood that isn't perfectly dry? It lights easily enough, but for the moment that 500C target should maybe wait. I don't want the thing to pull itself apart now.

I gather wood for each firing from the woodland floor - I live in a clearing, surrounded by wood. It's dead allright, I don't burn 'green' stuff, but of course it is as damp as the most recent weather/general atmosphere makes it. I do plan to lay in stocks of it somewhere where it'll dry more.

Another great tip borne of experience about slapping the floor with the peel. I shall have a peel by this afternoon...

Cheers, Chas.

[cobblerdave]

G'day Chaz
If your woods off the forest floor it will probably be be damp to certain extent .
If I'm to build a fire in the scrub no matter how dry, I always take the dead wood off the ground, on the trees .
Like you I don't buy wood in . Never have . Never will have to I hope. But I always keep
Everything I get off the ground
Regards dave

[Fred]

G'day Chaz
Well that was a lot of gobble de dock, wow, can you believe I'd come from a fiends place. A few more red wines were consumed!!! Sorry about that reply. Wasn't helpfull ;(
What might help with super dead wood . That isn't quite dry.
Kiln dry it in the oven!
That is under a 100 C
Lots of care taken with getting ride of ever last spark.
Stack you cooling oven with the next lot of wood ..., and dry your own.
Regards ( and apologies )
Dave.
PS yes if it helps I did suffer the after effects of " wine fever " cruddy mouth and sore head!

[chas]

Only one possible response Dave/Fred: no worries!

I've been kept off oven duties by virtually non-stop rain. When it hasn't been raining, work has got in the way. Work is the curse of the baking class.

Chas

[chas]

The first opportunity to resume... a fine day in prospect (though I stuck the brolly up rather than tempt fate ) and the plan is to light the fire and increase its bulk and intensity through a long, tempering burn - about 5 hours from 10 to 3pm and then put half a focaccia mix in the Dome and the other half in the ordinary oven. A simple J.Oliver basic dough but with oil, coarse salt and rosemary instead of his tomatoes. He says 20 mins at 220C.

I've taken on board comment about dampness of the dome and possibly of the wood too, so hope the patient stoking of the fire helps with the former and got some oak and apple logwood from the stores, split it down to banana size and stacked it on top of the woodburner last night and plan to finish the burn with a final stoking of that to get the cleanest effect. I'll be sorry if I have to abandon 'woodland floor' stuff, but I must say the difference is noticeable - not just in dryness, it's denser and probably more calorific. Another time I'll have stock of dried 'woodland' to try.

A nice little barrowfull of dried hardwood for a change:




By 2.30 the temperature had been a steady 200/225 for ages and I ramped up the fire size with a few bits of oak/apple. The effect was almost instantaneous - the dial was showing 350 within minutes. Maybe a touch too sudden...



The dough was through its second prove at 3.30, so both went in at the same time with the flame out but strong embers and the temperature still over 250C.

Both have now been removed - both a little overcooked, both delicious, neither a stand-out. Which I must admit is a little disappointing. However, onwards and upwards, there's a couple of potatoes in there now, gently baking away. We live to bake another day!



Houston, we have a problem:  there is a hair crack around the dome near the top. Bugger. It didn't reach its highest temperature, but despite taking care it probably had its fastest climb. Luckily, it's not a major structural thing, but it is a possible point of entry if it's ever rained on. So, K-rend has its limits...



Chas

[cobblerdave]

G'day
I have to admire you tenacity, your not going to let the cold shut you down are you !!
That crack is from what I can see at the junction of you dome and entrance way ?
I always developed a crack there even when I bricked over the entire dome. Uneven expansion is all it is. Did the same thing both times . Chased out the entire junction with the angle grinder and filled it with silastic ,making, I suppose an expansion joint. Could use a fancy high temp type I suppose but the one made for brick and tile is good to 300 C plenty enough.
This is the danger time for cracks, the upper parts of the dome etc are pretty much dry and the lower parts still damp. Best to let the oven cool between your firings and give time for the moisture to migrate to the dryer bits. Less chance of uneven expansion.
Good time for a good casserole, shame to waste that heat.
First make youself a short use door. Cut out soom ply to fit , wrap the entire thing in a couple of layers of aluminum cooking foil. Fit it to the entrance with a couple of bricks . Scared it will burn don't be it will survive a several cooks ... Well maybe a couple at least.
Next the correct temp ... Disregard the temp completely and time thats the only important thing .... Minimum 4 hours.
Next the meat , cheap cuts work best. Cut to any size same with the veg. Spice and salt and pepper to taste. Liquid regardless of size only add 1/2 cup.
Into a baking dish then entomb the whole thing by wraping it with continues layers of aluminium foil say 4 both directions. Don't poke any holes in it its to be completely sealed .
Then like I said its for 4 hours to cook.
This is a wood fired oven you have built the rule/cook books different.
If you want Webb search "kleftico" or "Greek lamb" in a wood fired oven.
Enjoy
Regards Dave