Where to the ashes go?
There is a slot toward the front of the oven that goes through the concrete slab into a space built into the concrete block base. You just rake the ashes into the slot. Even if there are still glowing coals they’ll be fine down in the ash pit. The ash slot should be deep in the entry tunnel about 2″ in front of the doorway bricks & angle iron. I put my slot too far forward. Not a functional problem but I have to worry about rainwater running in. The tricky part is that you have to decide where the slot goes before you pour the hearth slab. You make the slot by putting a piece of wood in the form to leave a void and knock it out after the concrete is set.