Smoke box material.

Hi chaps, which material is best for a smoke box. Brass or mild steel. Due to a number of reasons I can only use 2mm thickness for the part. So what are your views.

Assuming that the diameter is 140mm, as per your earlier post, 2mm is quite thin. I'd go for steel, being a bit sturdier than brass, esp if it's softened by silver soldering.

Brass would be easier to shape though.

Edited By Clive Brown 1 on 24/08/2023 14:34:58

2mm is stout in either material but brass doesn't corrode. Noel.

Thanks chaps. Ok looking at the drawings which do leave a lot of information out. It looks like the smoke box is made the following way. The outer wrap, then an inner wrap which goes the full length of the smoke box bar 15mm each end. Then there is an inner joining ring which connects the smoke box to the boiler. The smoke box door is a press in job which fills the whole front face of the smoke box.

I have a few problems here. First because I can’t roll anything thicker then 2mm how can I join the inner and outer wrap, would just silver solder along the edges do.
the second problem is that the joining ring is stated at being 1/8th thick, I can’t roll that thickness of material, so looking at making a former and hammering it to shape out of brass flat bar.

so at this point in time, I am going to go with brass, due to the corrosion issue and it’s easier to roll. However how anyone ever made one of these locomotives from the drawings I don’t know, it feels like half the information is missing. I know that there must be holes for the cylinder inlets but they are not on the drawings along with the missing door false hinge points. It looks like I am going to need to draw it all out in CAD before cutting any metal.