The heart of any bakery is the oven. This is still the case in your home kitchen - though these days we have so many other appliances to make stuff with, the oven has been relegated to a piece of furniture which holds up the cooktop. 

If you get into home baking, though, your oven takes on a whole new meaning. We start to analyse what it can do, and how it works. We play with things like sole baking, and other fun ways to use an oven. This section tells you a bit more about ovens, and some of the work I've been doing on designing woodfired ones too. Read on! 

Building Better Ovens

Written by Warwick Quinton. Posted in Ovens

Fifteen years ago, I saw my first 'setter' oven, and immediately fell in love. All I wanted to do from that point forth was to get my hands on one of those babies to bake in. It literally blew my baker's mind. I had no idea these things existed in my very limited bakery experience at that time.

Setter Oven

Reality set in (no pun intended) soon after, when I found how much one would cost. I would have to mortgage everything I had (again) just to get a small one. Love turned to disillusionment fairly quickly. I wasn't disillusioned with the oven, or the price - far from it. I could see the value of disposing with all that crap in my bakery - the tins, the trays, most of the racks, the moulding machines, the dough cutter, two other ovens (an Italian rack oven and a Spanish deck oven - both in themselves very good pieces of equipment, but showing their age after leading a hard life in my bakery) and pretty much all the other industrial paraphenalia I had accumulated over ten years of running a sourdough bread factory.

For those who don't understand baker's jargon - a 'setter' oven is a term applied to an oven that is specifically designed to 'set' dough directly on the sole. It's not a 'deck' oven - though these can be modified to 'set' into, using special bricks. There is a bit more to a setter oven as well - suffice to say that they use thermal mass to heat the baking chamber, rather than an element or a flame directly. This gives them a different quality of heat to bake with, very suitable for breads baked on the sole, without tins. Thus, it tends to be that artisan bakers love them. They are a simple and direct tool for baking bread.

Bakery Paraphenalia

The true value of simplification, and the dollar costs associated with this kind of reinvention, caused me to sit down and take a good hard look at what I had created. I resolved that I had taken a wrong turn somewhere. And I became deeply disillusioned with everything I had done. I lost enthusiasm, not for baking, but for borrowing money. Bakeries just meant more and more money, as had been my experience up to that point. 

Cut to the present. Fifteen years later, and I have no mortgage and no bank manager. Admittedly, I also have no house of my own either. But what I do have, I own, lock stock and barrel. Beyond this, I have no bread tins (actually I do have some - but relatively speaking, none at all), no trays, racks or ageing continental ovens. No moulding machines. No dough cutter. In fact, I reckon I've got the idea now; figure out what you really need, and get rid of everything else.

To earn a living these days, my equipment is minimal. A small dough mixer, some plastic boxes, some wooden boards, a few fridges, some work benches, a kitchen on wheels, and in it, a woodfired setter oven. That's it. I pay my bills each week and I know exactly how I'm going financially from month to month. 

Reinvention has happened on a number of levels, and yes, I had to lose everything to make this happen. I also had to adjust the way I thought about things, and this is where the fun starts.

Why did that setter oven that I had fallen in love with cost so much? On a certain level, the people who made that oven knew its value to the baker.

The setter oven itself doesn't cost a fortune to build, really. From experience, I can say that the amount of refinement and development that went into it would have been huge, and that would have cost real money - but the reason anything is priced as it is actually reflects its true value.

The value of baking better bread is returned time and time again to the artisan baker, and that is why they are prepared to invest big money in an oven that does what they need it to do better than anything else. 

So what does someone do if they want to bake great bread, but don't have the substantial capital to afford a setter oven? Last time I looked, a quality setter oven was priced at upwards of $35,000 for a small unit. A large setter comes to over $100,000, and that's just for the oven. Installation and the necessary bits to make it run - like gas and 3 phase power - are not cheap to install. While access to capital may be available, it's worth breaking down these costs into how many loaves of bread you will have to bake to pay for it. And then, divide this by about 5, as typically it will take 5 years to repay a lease. After that, you have a 'free' oven - except for the gas or electricity used to keep it running. And of course, the cost of maintenance, which escalates as an oven ages. So if these sums just don't add up, you can either put that dream back into the ether for now, or start thinking outside the square.

For me to have a setter oven myself meant that I actually had to make it, because I lost my appetite for debt. The learning curve has been steep, but it is levelling out now. Years ago, when I contacted Craig Miller and started talking to him about making a setter oven to bake bread in, I had no idea that I would end up designing and building the oven with him. We have both been on a journey to this end, and after building three prototypes and modifying two other ovens, the objective has finally been achieved. We now have an oven that works. And while the cost has been relatively high in terms of lost hours of time, as well as steel and brick and actual fabrication, the dollar cost has been quite reasonable so far. 

Of course, it has to be said that our oven is quite a lot more than the sum of its parts.

The setter oven I fell in love with fifteen years ago was heated by gas and powered by electricity. It had all sorts of technology built in - fans and computers and thermostats and plumbing and high tech insulation and LEDs and lots more I don't even know about.

Our setter oven has no moving parts, is made of steel and brick, and is heated by fire. There is no need for electricity.

If the setter oven I fell in love with years ago broke down, you would need a highly trained technician (or two) with lots of specialised equipment to come and fix it. And a plenty of idle funds in the bank to pay for their skill and equipment.

Our setter oven doesn't break down. One day, some of the steel it is made out of might fatigue and bend, but if it does, an angle grinder will most likely be employed to fix it. Or maybe just a crowbar. New steel may need to be cut and fitted, and Craig may have to weld it up (I don't yet know how to weld). But this is unlikely to happen for a long, long time. And it's a worst case scenario. And a general purpose handyman could most probably fix it, with a phone call to Craig or myself to walk them through what needs to be done. 

You see, our design brief was to keep it 'third world simple'. No power, no moving parts. The ovens we make need a drill, a crowbar, a spanner or a hammer to fix. Not much else. We chose to stick with woodfired ovens, but to work towards making them really efficient and really clean. 

This has meant that we have spent five years studying fire science. It turns out this is an area that seems to be going ahead in leaps and bounds, with people all around the world applying considerable brainpower to the subject. It's interesting that something as simple as a fire fuelled by a combustible material like wood would become so important to so many people - but it has, for a multitude of reasons.

With our third generation of woodfired ovens, we are starting to really understand what we are doing. Indeed, now the refinements are coming into our designs, and the ovens are getting better and better, very fast.

Working with the element of fire, but without electricity, has meant gaining a deep understanding of how to make heat travel further and hotter. Our fire becomes flue gas, which flows around the outside of the baking chambers. We did play around with moving flue gas around with fans a few years back, and found that all we were doing was adding something which would break down later. Instead, we gradually figured out how to make fire 'stretch'. In the process, we researched 'rocket' stoves, as well as, more recently, 'bell furnaces'. The endpoint has been, thus far, what we term 'high flow' fireboxes, which continue to yield huge rewards in terms of efficiency. The beautiful thing about pursuing efficiency is that ultimately you get two birds with the one stone - when you make a fire more efficient, it inevitably makes the fire burn more cleanly. 

There have been more challenges than simply making the fire burn better and cleaner though. A great deal of the work in prototyping our ovens has been done for the purpose of making the oven bake more evenly. All ovens, especially woodfired ones, have hot spots, where the heat 'pools'. Our research has shown that round shapes are less prown to heat build ups, but from an operational point of view, a baker is happier to load their bread into the baking chamber from an open side, as loading in bulk is faster this way. When you open a whole side of a baking chamber, whether the oven is round or square, you force heat build up down the back of the baking deck simply by letting the heat at the front go out the door. So this has presented a design challenge - one of many that other oven designers have faced before us. There are a multitude of novel solutions to this issue - making a deep baking chamber and using a setting device rather than a peel is the most common solution, and this works well. But our low tech approach means that we have to think about these issues differently. It's all about making those flames travel further and further without using fans. 

Warwick Quinton using his oven

Of course in the end I just want a great oven that I can use. What has happened, as a result of this newfound obsession, is that I have been forever sentenced to using prototypes. It's a mixed blessing - sometimes I just want to get on with baking easily and without thinking about the oven. Most weeks my day job is to bake a few hundred loaves of top quality sourdough bread in a reasonable time, you see. But my Luna, as the third prototype, does the job pretty well. It would be great if she did the job a little better - and if that takes trying stuff out to see if it works - well, so be it..

Which, in the end, is how Craig Miller and I go about building better ovens. 

Now we have been able to make one successful oven, we are pretty keen to make more. In my mind, the bakery business has become too industrial in scale, and this is true of the artisan baking business in some ways too. The high cost of entry is keeping bakers enslaved to feeding the banks, and not bread lovers. Everything is going too fast. If Craig and I can help people into following their dreams in an affordable and human scale, it is possible that the bakery business can start becoming truly revitalised, decentralised and regional. But at the same time, if us bakers can also start to become aware of our energy use, and the effect our wastage has on the environment and the soil that grew the grain, we will be doing something far more important than simply supplying sourdough baguettes to satisfy Saturday's appetites. 

If you would like to have a closer look at the fruits of our labour so far, have a look here.

 

A $250 woodfired baker's oven

Written by Warwick Quinton. Posted in Ovens

A few months ago, I set myself a bit of a challenge. I decided to see if it was possible to make a decent woodfired baker's oven, entirely out of recycled / repurposed materials, for $250 or less. 

Woodfired recycled baker's oven

I didn't want to spend months making it, either. A couple of days, tops, I thought. And this oven needed to be able to bake a dozen loaves of bread at a time, and also to be able to bake other things, like pizzas and roasts, without consuming half a forest to make a few morsels for dinner. 

I've been to people's pizza parties quite a few times. You know how it goes, the pizza party requires the host to fire up the woodfired oven at ten in the morning, and by late afternoon, when everyone is half drunk, the oven is almost hot enough to bake a pizza or three. And that's it. A whole tree, for a pizza.

So, in the name of forests and their preservation, to make this oven work, the flames must also do some work. Meaningful work too - the work of making a baking chamber hot, quickly. 

Firebox without a door

In my experience, the home made pizza oven is special to the people that take the time to build them - kinda like a billy cart, or a crochet blanket made by grandma. It's got more going for it than the BBQ, which you can just buy from the local hardware store. The pizza oven has to be designed and built by hand. Often, it's a project embarked upon with a friend, whose grandfather was Italian, and they taught him just the right way to make it. So, after getting special oven bricks and fireproof insulation, and sand and clay, and the custom made door, the flue and the cement and the tools, it only cost two grand, and took two and a half months to build (in between doing the day jobs).

But the pizzas that it makes are just AWESOME. The end justifies the means.

Yep. As you guessed, I didn't want to be that guy. If I was going to spend two grand on a pizza oven, I would want it to do a lot more with a whole lot less. For that much money, you can buy a pretty decent gas oven, and it will also boil water!

Anyway, I had given some thought to my pizza / bread oven design before this. As those of you who read this website know, I'm not a fan of 'black' ovens. I like ovens where the baking chamber is not also the firebox.

Supporting steel

A 'white' oven allows the possibility of continuous baking, as well as being able to heat from cold in a short time - depending on the design, of course. Design, when push comes to shove, can be the undoer of a great idea, if not enough time is spent on it. Or not, when the design phase is well executed. Too often in my projects, I spend too much time on building and not enough time on design. 

So I was thinking of an oven made from a 44 gallon drum. For some time, I have seen that flame doesn't travel in a straight line - it kind of loves the vortex. So a cylinder allows heat to wrap it up quite well - allowing the flame to be a flame, if you like. The problem with a cylinder is that bread and pizza need a flat surface to bake on. A cylinder, when laid on its side, does not provide flat surfaces.

As it turns out, flat surfaces are easily done. Who would have thought?

I did a bit of a drawing on my chalk board. My guess was that I woud need the following materials:

Recycled materials

  • a 44 gallon drum, and the lid
  • 180 standard bricks (plus or minus)
  • some pavers of varying thickness
  • a decent sized piece of road grid (cast grid material of some kind)
  • a piece of stainless steel or similar as a flame baffle
  • an iron gate or fence as a kind of frame to hold pavers above the drum
  • a piece of flat steel to support bricks 
  • some hebel to insulate things.

In the end, I also needed to purchase some bits brand new. I needed cement, fire clay, some very thin pavers, a diamond angle grinder blade to cut them, and some high temperature glue. Luckily, Bunnings had a special on sheets of 50 mm hebel as well. 

A sketch in brick

I managed to get everything else from Cessnock reuse and recycling centre at the tip, as well as a few bits and pieces I had lying around at home.  

I spent just over $250, including everything except fuel for running around. I got the oven built in two days, and it bakes 12 loaves perfectly. It also does pizza and a roast dinner with ease. It heats up to baking temperature in just over 45 minutes.

As part of the design process, I built a 'sketch in brick' - a kind of 3D, real life version of my blackboard sketch. Then I pulled it apart and started again. I love working with things like bricks, because it allows you to do that.

I discovered the problems with my chalkboard design. So back to the local tip I went, to find more appropriate bits to use in the construction. Working with recycled bits can be tricky, because you may not get what you were thinking to get - but with a bit of lateral thinking, I was able to adapt imperfect inputs to my purposes.

Woodfired Sourdough bread

I still have a few tweaks to do - it needs a firebox door which lets in lots of air, and I haven't yet bagged and grouted the pavers on the roof. But for a quick, cheap oven, I reckon this one works a treat. It bakes great bread. I've used it for pizza as well, and everybody thought they were pretty good too. I've even done a roast dinner in it, which I have to say was superior to roasts done in the home oven.

The build process itself is another article - there is a fair bit of detail involved. I also want to do a bit more on the oven before I write this as a 'how to' article.

At this stage, I'll say the repurposed, recycled home baker's woodfired oven is largely a success. It answered the brief well. It isn't pretty, and it has some shortcomings - I struggle to get it above 300 degrees, for example. But it turns out that isn't necessary. The nature of the heat still creates really good pizza in less than 5 minutes. 

Version 2 of the Recycled Woodfired Baker's Oven is already planned, and will happen quite soon. It improves on the original design significantly, while not costing a whole lot more to build. It may take a bit longer to assemble, but remains very low tech. My plan is to rebuild with existing materials, adding a few key changes to the way it is flued to enable even faster heating, while also making the oven hotter.

Stay tuned for progress.

 

 

 

 

Luna lands and blasts off!

Written by Warwick Quinton. Posted in Ovens

After some four years of prototypes, including Bertha 1 and Bertha 2, Luna has indeed landed. With precision.

 LunaIt's amazing what we have learned from building and using ovens - both woodfired and 'on the grid'. If I had a dollar for every time I cursed Bertha (and then rapidly retracted my curse, as I knew she'd kick me where it hurts when I wasn't looking later on), I'd have built another ten ovens by now with the proceeds.

Essentially, both Berthas started life in a state of deeply confused creativity.

Bertha 1 was a swiss army knife - a cafe cooker and a baker's oven. She had a useless bottom deck, and arrived without any insulation. She burnt the hairs on our chef's legs so many times they had to wear long trousers, even in midsummer. She burned out the exhaust system, and melted herself out three times in three different places. Despite all this, I managed to tune her effectively enough to pump out a couple of hundred awesome loaves every Saturday morning - and she handled her cooktop duties well, after lots of tweaking. She really was a comedy of errors, though, and the best learning facility a baker and a boilermaker could ever have. 

Bertha 2 was more focussed - a purpose built baker's oven from the getgo. She still managed to burn out her first firebox inside 6 weeks, but when we replaced much of it with stainless steel, she ran like a trojan. Then I almost destroyed the bottom deck by accidentally setting a fire inside it (seriously!). But, she was made of stern stuff, and survived nonetheless, with more brick being added in there. Bertha 2's big problem was that she was designed for 7 day a week service, but in the end she only got to be used for two or three days (have a look at the stories concerning Denison Street for more about this). However, as a result of her reduced role, her unsuitedness to short baking shifts really became a major issue. She weighed almost 4 tonnes when fully tuned, and it took a full day to get those bricks hot. In addition, her insulation and flue design needed major work, in order for her to heat both decks within a reasonable time frame evenly.

Living with Wal

Written by Warwick Quinton. Posted in Ovens

(this article comes from my blog post of November 2011)

Call it my personal foible - I like to name pieces of equipment. I find that it humanises them, and reduces frustration with them when they don't work properly. Over time, they develop a personality too - via repeated experience with these inanimate objects, a certain character of operation becomes evident. So a name has to fit if it's going to stick.




Meet Wal, our new oven.

 


Bertha, while inelegant, was certainly big and powerful. And you didn't argue with her or she would burn you badly. Wal, on the other hand, is a reduction of his brand name, Waldorf. 

Wal was born in July 1981, somewhere in Sydney, I believe. This information is on Wal's nameplate. I like that. He declares where he's from and how old he is right from the getgo. Wal's an upfront kinda guy, that we know.


He's a large caterer's oven, with two baking chambers. No 'fan force' in Wal - and that's perfect for Wal's new role as a baker's oven. Wal is powered by gas, not wood like Bertha was - so he doesn't have the grunt Bertha had either.

I've had to tune him to bake bread by creating stone decks inside his belly, as well as layers of bricks to varying thicknesses above, to the sides, and below. I've had to adjust the distance of the racks from the base too, which is where the heat from the gas flame comes from. Now he retains heat better, and cooks top and bottom evenly. I'm also getting good orange colours on the crust. 



So Wal has adapted to his new, semi retired role very well. He gets used extensively on weekends for our bread run, and through the week for some cakes and catering duties. We've done a bit of work to his gas lines so he burns better. He's pretty snazzy with baking tinned breads and cakes - actually holds more than Bertha did - but his sole baking skills are not in the same league as Bertha by any stretch of the imagination. Wal is slow at baking sole breads, so we end up with a thicker crust. Thus, I call him a crusty old bugger.

Bertha 2 on butcher's paper

Bertha 2 is being planned for out the back here in Denison Street. Bertha 2 will be 2.5 metres wide, by 1.5 metres deep. She will have 2 decks, with a good 25 cm height in each. This means we will have about 6 metres of baking space in Bertha 2. To give you an idea, we currently have about 1.5 metres, so this will be a massive step forward in terms of capacity.

But for now, I have Wal. I fire him up well in advance of any baking I need to do so his stones get good and hot. I make sure I keep plenty of water up to him for steam, and I keep his doors closed for fifteen minutes at a time during every load so that he holds his temperature. I keep an eye on the pilot lights, in case they get snuffed out by a bit of cross draft in the kitchen. If they blow out, we lose temperature without knowing it, so then we lose bread.

We've come to a workable arrangement - Wal can handle about a hundred loaves in a baking session, which takes him about twelve hours to bake. He can set about eight to twelve loaves at a time. Bertha could do the same thing in about six to eight hours - so Wal drags the chain a bit. But hey, he's over thirty years old now. I reckon ovens age at about twice the rate of a human, so Wal's an old fella. Taken in context, Wal does alright.

I'm just wondering how Wal will react to Bertha 2 when she sets up shop just outside his door...

 

Building Bertha

Written by Warwick Quinton. Posted in Ovens

Bertha is our woodfired oven - or more correctly, she is the name given to our prototype woodfired baker's oven. There have been plenty of woodfired ovens built - but none like Bertha - she's a baker's oven for the 21st century.

She is an efficient, fast and 'easy to live with' oven, which is intended to be used in artisan bakeries - but she's 'off the grid' - meaning she happens to be powered by wood, or even food scraps, rather than electricity or gas. Yes, she can and does save money on energy costs too. And she burns very cleanly. That's the idea. Every baker's dream oven.

Her first incarnation, Bertha 1, lived in the SourdoughBaker Cafe, in West End, Newcastle. My mate Craig Miller and I designed her, over the phone, from scratch. There's more about that story on one of my blogs,  so I won't repeat it here. But if you are interested in SourdoughBaker Cafe, and it's oven, and other stuff, have a look at this blog too..

 

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