AALS Convention there are 2 small photos off a boiler with the caption "Les Irwin's Duplex 2205 alloy boiler the prototype for the new AMBSC Boiler Code Part 4 available shortly" There is a short mention in the report that said it has been approved. I have never heard of anybody building an alloy boiler before. I would imagine they would be easier to build but surely they would need a steel liner in the fire box. I'm intrigued can't wait to see the new code. Lee MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.