2nd layer over oven + chimney

Over the initial heat mass layer comes a heat blanket, then stucco lath (mesh) and some rebar. At the same time I decided to cast my own chimney using a galvanized chimney tube and a cardboard tube I found at my home improvement store. The cardboard tube is actually for pouring concrete columns, but it fit well over the metal chimney pipe. The pipe cannot be used by itself as it will rust over time, also it is only available in a 2' length, and I needed a chimney height of 3'. So I connected 1 1/2 together and surrounded them 1" mesh (chicken wire) for strength. The chimney is held in place by two pieces of rebar that were bent to roughly a right angle and then tied together with a short piece of rebar. The galvanized pipe has a 6" diameter, the cardboard tube an 8" diameter.