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.

 

Woodfired Ovens