I've had an Ooni Koda pizza oven since the kickstarter, and I've hacked it since I've had it. While it's a really good portable pizza oven, anything can be improved. In my case, I've been tinkering with turntables for the Koda for a while, in order to ensure even pizza cooking. My last turntable effort worked pretty well, but only lasted for almost 2 years. Eventually, the high-temperature epoxy gave way, and the stone separated from the lazy susan.
So, I wanted to start over with a different design. A better design, that didn't rely on epoxy. A design that, as things turned out, would fail the first night I used it. Yeah, don't run out and buy these parts, you don't want to build this. Instead, read through and relish my failure.
I did discover a different, useful tool, though.
So I went to the scrapyard and got a new sheet of stainless as a base and a strip of 3/4" wide steel. In a fatal decision, I bought a 12" lazy susan as my turntable, plus all the screws and everything else. My 13" corderite stone from the prior turntable was salvagable, so I reused it.
The really challenging part of this design was going to be perfectly centering the lazy susan on the stone. With a 13" stone, I only have about 3/16" clearance on either side, so I couldn't afford any wobble. I had to reach back to my 7th grade Geometry class and remember how to find the exact center of a circle using a compass.
Eventually, I got everything perfectly centered and blue-taped together so that I could mark holes for the metal strips, and turn them into retaining tabs to hold the stone.
We drilled them, and fastened them on with tiny stubby bolts. These bolts had taken some doing to find; I was at Eagle Point Hardware for forty minutes searching through the cabinets with one of the very knowledgable women there, and eventually found these stubby metric bolts intended for repairing appliances. But they were the right 5/16" length. I also centered it and attached it to the sheet steel, so that it would be stable and centered in the oven.
I slid it into the oven. Success! It fit perfectly and spun easily. Now, to make pizza!
That night I was making pizza for a party -- 8 pizzas in all. I grabbed my dough and toppings, fired up the Ooni, preheated it for half an hour, and got ready to bake.
My first pizza, a margherita, was perfect. The easy spinning of the turntable let me even out the heat and it had a beautifully spotted crust and no scorching.
But, I had 7 more pizzas to make. And around pizza #4, things started to go downhill. The turntable started sticking, and not just a little; it completely locked up and couldn't be turned. I burned the crust of two pizzas. What was wrong? The oven was 800F and the guests were arriving; there was no pulling it apart to check. I grabbed my old pizza spinners and did things the hard way.
I got through all of the pizzas, and got them ready to serve. Pictured here was my successful hack; I bought two folding cake layer racks to use as multi-pizza racks. These worked really well for stacking six pizzas at once and making sure their crusts didn't get soggy.
Later, I took the turntable apart. What had happened is that with the heat, the 12" lazy susan had warped, which meant that as I spun it, it would bind where the ball bearing track was now too tight. This wasn't fixable, and even if I swapped in a new lazy susan, it would happen again.
In the end, I decided to fork out for a Zifa Pizzatwister, and pay for (and wait for) the shipping from Germany. More blogging once I try it out.