Flying Saucer

[Neil2]

First - dig the holes. I used a hand held post hole digger to go down about 4ft. The last foot was tough going and I rented an electric jackhammer with a long bit to loosen it up. This "pile" system would also work if you are worried about getting below the frost zone in clay clay-till soils. Next I supported a couple of 3/8 re bar in the holes and pored in concrete. The part that will be underground does not need the carboard tube forms (unless the soil is really granular or sandy and keeps caving in). The carboard tube forms are readily available at your local lumber yard or builders supply. After pouring the tubes, I bent the rebar and formed up a 5/8 in plywood platform to support the 4in structural slab pour. The last photo show it ready for the concrete. The circular shape is achived uisng strips of lighweight pegboard lined with tech tape curved against blocks screwed to the plywood. The ash drop opening is formed with a peice of 4in pcv pipe wired down. Note: always try to use round shapes, avoid square "inside corners", for openings in structural slabs.

[Ken524]

Excellent pics! Keep 'em coming. That's a really neat project.

[Neil2]

After pouring the 4 in structural slab, I "climbed" the form up a couble of inches to support an inner ring to act as a form for the 5 in insulating layer. This is 6 parts vermiculite, 6 parts perlite and 1 part normal portland cement. The second photo shows the forms off and the hearth layer on top of the isulating layer. Next I started the dome. I found I could go up about 4 courses without internal support. The last photo shows how I used screws for spacer to hold the angle untill the mortar set. The angle changes a bit for each course so I used 1 1/4 in screws, 1 in screws etc as needed. The mortar is refractory mortar. This was buttered on for about the first 1/3 of the brick on the inside tight joints. When I used refractory mortar for the wider part of the joint I found it shrunk and cracked when setting so for the outside wider part of the joint I used a mix of 1 part refractory mortar to 3 parts sand. This may actually be stronger than the neat mortar for the wider joints.

[jengineer]

love the foundation - taking an basic design and making changes to it to make it your own. Nice evolution

[Neil2]

Thanks Ken,Jr
The remainder of the dome was built on styrafoam supports. This was a tip I picked up from this forum and it worked great. When I started, I rented a proper masonary saw with water bath to do the bulk cutting into 2/3, 1/2. and 1/3 bricks. Did all the cutting in a couple of hours. As you move up above the 4th course or so, you have to start doing a "bevel" cut on each brick to keep the inside joints as tight as possible. I did this using an ordinary chop saw with a masonary blade. I soaked the bricks in water for 1/2 hr so that the blade was "wet cutting". If you cut dry bricks the blade will wear out fairly quickly. In the second photo you can see a bundle of cheap chopsticks which I used to bridge between the styrafoam supports as needed to hold the bricks as I worked up. I took my time, doing a couple of courses at a time and letting the mortar set up overnight before doing the next two courses. Last photo is me inserting the keystone set.

[fullback66]

Everyday that I look at this forum someone impresses me. Great work Neil. That is a very unique design.
fb66

Send more pictures.

[Frances]

I like it, too!

How on earth do you make a heavy thing like a brick oven look as if it is floating? It looks really good.

[Neil2]

Thanks all.

The hardest part to figure out for me, was the opening and lintel. I actually tried a couple of different things before hitting on the one I used. It is hard to describe clearly. Basically you will need two lenghts of angle iron - I used sections of the "T bar" reinforcing you can find at lumber yards. Because my entry is tapered the two pieces are of unequal lenth. The innner one goes in while building the dome and supports the dome. the outer one helps supports the vent. Outside of the vent, I formed up and poured a layer of the vermiculite/perlite insulation. Note the pale white bricks. These are lightweight insulating brick I got from a potter (potters are a good resource for materials and techniques). These form a thermal break for the outer lintel which is poured rienforced concrete. The aim was to keep the opening fairly shallow so I didn't have to reach in a long way to tend the fire and food.

[Acoma]

I got an idea, why not the FB olympics? Who can make the fastest oven with best character and draw of smoke? Maybe relay teams? One to 3 members per country?

[Neil2]

The first photo is of the 2 in poured reinforced concrete "belt" that holds it all together. This extends up to the height of the first soldier course. The second photo shows the screeding frame for the 5 in thick vermiculite/perlite/cement insulation layer. The final finish is two coatings of acrylic stucco painted on. The third photo is the concrete table. I set the height of this level with the hearth floor at 43 1/2 inches. My wife wanted it high enough so she would not need to bend down to see in. (I have a 5ft 4in wife - if you were issued a different size one you may need to adjust the height.) The table is 1- 1 /2 concrete, poured with a little green conc dye added. It was then ground smooth and polished. I set it tangent to the oven at about a 45 degree angle to the door. This allows you to get near the opening without reaching over a table and still provides a convienent working surface. The last photo is a shot of inside of the brickwork.