First Firing

Ducked home tonight and whipped out the mold. Dome looks good!

Scraped what sand I could off the roof of the dome and then cleaned up the floor. That did mean squeezing my top half into the oven to scrape the floor with a trowel.

Then it was time to light the first fire. Modest admittedly. Four sheets of newspaper...but the first fire none the less.

Timing

This is the third weekend that I have worked on this oven. The days have been pretty casual, still allowing for a sleep-in and lazy breaky whilst reading the paper.

On the first weekend I built the metal base frame and set it in place.

On the second weekend I finished off the base by laying the cement fibre sheeting and a layer of pavers.

During the week I did a few little jobs in the evenings to make sure that everything was ready to get the dome built this weekend

This weekend I whacked up the dome. It prob only took about 6 hours of actual time on the job.

Next week I'll have a bit more time on my hands. My plan is to have the oven finished by the end of next week. That will mean:

• Covering the dome in insulation, chicken wire and render
• Building the smoke chamber and installing a chimney
• Laying some slate around the outside of the dome.

We'll see how it goes!

Some thoughts on the Dome

As you can see, at this point things aren't looking very pretty.

I've used up left over mortar to start a render coat on the outside. I don't really think that this is necessary, as there is still a layer of insulation to go on prior to the finishing coat of render being applied.

A coat of render at this stage though,will

• use up left over mortar
• seal up any gaps between the bricks
• even out the dips and hollows of the bricks to provide a consistent thermal mass layer.

Sunday evening. The dome has been laid in a weekend, the dome mold is still in place to allow the mortar to set the bricks in place (I'll prob pull it out tomorrow night), and the sight has been cleaned up.

My back is aching, my hands are stinging and my hamstrings are feeling pretty tight from bending over all weekend. I'm feeling pretty content that I've created something useful and got some exercise at the same time!

Building the Dome | Part 3

Once the dome mold is set up, it's just a matter of setting the rest of the bricks in place. I kept going in concentric circles, setting each brick in place as I went.


When I got to the last few bricks, I had to knock a few edges off them to make them into wedge shapes so that they would lock together to support the dome. Then it was just a matter of getting as much mud in between them as I could to fill up the gaps.

I'll leave the mold in place overnight to allow the mortar to set the bricks nice and firmly in place.

Building the Dome | Part 2

Once the dome has got to this height, the bricks won't stay up.

I had to build a platform inside the dome, on which I could build a dome mold out of sand.



To do this I used a couple of lids off meat tubs, set up on a couple of layers of limestone blocks. Turned out to be just the right height.

I then packed the gaps with some fertiliser bags, and shaped the dome. The dome took two 10kg bags of sand.



Postscript: In hindsight I should have used a light (8:1) mortar mix to make the mold as suggested in Russell Jeavon's book, or covered the sand in wet newspaper or plastic. There is now a loose layer of sand on the ceiling of my dome that I am going to have to get off somehow. I think this is going to have to involve getting the top half of me in the oven with a wire brush on the end of a cordless drill!

Building the Dome | Part 1

Once the first course has been laid, the jig comes into it's own as I lay the next 3 to 4 courses. After about 4 courses, the angle of the bricks becomes too great for the brick that is being laid to stay put long enough for the mortar to stick.
Then it's just a matter of going a round and a round setting each of the bricks in place.

Some Brick Laying Tips

• Ensure that you mortar mix is not to wet & not to dry. It should just hold together, but get creamy if you work (slap it around) it abit.
• A dribble of detergent in the mix will make it more workable
• Make up small batches at a time. I've used a Cockburn Cement Creme Mortar mix. It's one of their dry mix products and comes in 30kg bags ready to go. You just need to add water and mix it up.

• I used 4 of these bags of mortar to lay the bricks for the dome of this oven.
  
• I plunge each brick into a bucket of water just before I use lay it. I helps the mud to stick to it.
• Watch your hands. The lime in the mortar makes abit of a mess of your hands, and is pretty painful when it comes into contact with any wounds. If you've got soft pen-pushing hands like mine, I'd suggest using a barrier cream and gloves.
  

Laying the First Course

Easy as! A line of mud around your marked out circle, a wedge of mud on the long edge of each brick, and away you go.

I've drilled a couple of teck screws in to each side of the door frame. This will give it something to tie it into the mortar of the wall.

I set aside the weekend to lay the dome. During the week I made sure that the dome and door was marked up. I had my bricks split in half and piled up next to the site. I'd bought 3 bags of mortar mix (turned out I needed another one). Every thing was ready to go as soon as I dragged myself out of bed on Sat morning.

Marking up the Dome and Door

Now that I've got my centre point, I can now mark out the inside edge of the dome on the base. This will provide me with the guide for laying my first course of bricks.


Once the dome has been marked, it's time to position the door. Again I've used patio tube for the frame. This door frame has been made to suit the door that I will be using. It's off an old Metters stove. It's a bit smaller than I would like, but it'll do the job, and should look pretty good.

The Jig

This is the jig I use to place the bricks in just the right spot to get a nice even dome.

It's made from 10mm steel rod, with a piece of 40x40 angle welded onto it at right angles.

The length of the jig will determine the size of your oven. It determines the radius of your dome.

For this oven, I'm using a jig 500mm long. This will give me an oven with a diameter of 1 meter.

This is a bit smaller than the 1100mm diameter of the first oven I built, but I still think it'll be big enough.



The next job is to find the centre of the dome and mark it.

I've set my dome back a bit from the front in order to provide room for the smoke chamber and work area.

Once I got my mark, I stuck down a 10mm washer to stabilise the jig as it pivots.




Footnote: The washers didn't last into the second day of laying. I ended up drilling a 10mm hole in the brick (to about 4mm deep). This worked much better.

The Base | Part 2

The top's base is a sheet of 18mm compressed cement fibre. I've laid a single course of 50mm pavers on top of this, with the beveled edge down. This will give a smooth surface to the base of the oven.

I'm taking a bit of gamble with just having one layer of pavers, but I reckon it'll be ok. It will just mean less mass for the heat to sink into and release from. I don't think that this will be such a huge issue for a back yard oven.



At this point, all I need to do now to finish of thebase is to split the pavers on the edges to ensure a nice fit inside the steel frame of the base.

The base was finished off on the second weekend of the project. Ready to lay the dome

The Base | Part 1

For this oven, I've decided to make the base out of steel. I'll then clad it with pine decking left over from the main deck.

I've used galvanised patio tube.
Obviously the base of the oven can be made of anything. All it does is hold your oven up at the right height. I'm not much of a brickie, and the straw bale option that I used last time was a bit too time consuming and messy. I find steel nice and easy to work with. Easy to cut and weld to just the right size and shape.

The top is 1500x1500mm square. This will be just the right size to fit the oven on and still give some room at the front for a smoke chamber and a small work area.

The legs are patio tube also. Set into the ground with rapid set concrete at about 400mm.

The top of the base will sit at about 1000mm from the patio decking. I've found that this is just the right height for me to be able to stand just back from the oven door and see into the back of the oven.

This base frame was made and set in place on the first weekend of the project.

Getting Started

Before you begin you'll need to think about:

Resources

• Some of the resources that I found helpful can be seen on the Helpful Resources Page

Design

• I prefer a simple dome design with an internal diameter of 1100mm. This seems to be the best size for average back yard use.

Location

• My first oven was out in the open, so a flue was not necessary.
  
• However Mark II will be partially under the cover of the back patio, so I will have be make up a smoke chamber with a flue stack.

Materials

• I prefer to use found or recycled materials where I can. For the base of my first oven I used straw bales that I later rendered.
• The floor of the oven was made up of a 100mm layer for concrete with two layers of paving bricks on top (beveled side down so as to provide a smooth, flat cooking surface. I used about 50 pavers.
• The bricks for the dome where what we call 'recycled reds'. These bricks had been a house, then a drive way, and are now an oven. I used about 50 full bricks.
• The mortar that I used was a basic brickies mix. No special additives or secrets.
  

Tools for the Job

• I made up a 'jig' for setting the bricks of the dome in the right places.
  
• It was a piece of rod the length of the radius of the oven (i.e. 550mm) with a small piece of angle iron welded on the end.
• A brick bolster and small mallet is the perfect combo for splitting bricks into just the right size.
• Mortar can be easily mixed in a wheel barrow with a shovel. If you have access to powered cement mixer it may make it a little easier.
  

Finish

• I simply covered the completed dome in rockwool insulation, a layer of chicken wire and a couple of coats of sand/cement render.

Welcome

I built my first brick oven just on two years ago. It took me about six years of thinking about getting around to building it, and a weekend to build.

A few people have been asking about my wood fired oven. Questions like:

• How hard was it to make?
• Did it take long?
• What sort of bricks did you use?
• Did you use a plan?

Fortunately, I had the fore-sight to take a few pictures as I went. Today I've bitten the bullet and decided to put the pics, and a bit of a story about how I built it up on the web to make them easily accessible to who-ever might be interested.

Today's been a bit of a busy day. I started on my second brick oven at the new house. Clancy's collapsed in a heap on the floor (his favourite way to spend a bit of free time). I'm feeling a bit stiff and sore, so this will probably be all I post today.

My plan is to share the process of how I built my first oven, as well as the progress I make on Sev's Brick Oven Mark II.