After letting it rest for a day or two, secure the chimney pipe at the top using some cob mix, to keep it in place. Now you need to give your oven some time to dry and harden. Let the oven dry for a week or more depending on how cold and humid your place is. Touching it before the cob has completely dried can cause the structure to sink in.
When the structure seems strong enough for use, remove all the sand from inside it. And finally fix the door to it. To make the door you can either use wood or a metal door. Whichever material you choose, make some holes near the bottom of the door, from where the oven can suck in air for the fire. The holes should be made only in the bottom 10 inches of the door. If you’re planning on making a wooden door, you must coat the inner side with a half inch thick layer of cob. This will prevent the door from getting burnt. And here’s what your wood fired oven will look like.

click to enlarge
Lastly, just remember that this wood fired oven construction plan requires a lot of patience, as it can take anything from a week to fifteen days to complete. But for sure, your patience will be rewarded with the sumptuous baking treats you’ll get to enjoy once you’re done with the project.