If you have read my thread in the General section "New Build Ponderings" you will be aware that I am looking into possibly building a GWR Barnum class in 5" gauge. I have a particular interest in Dean and early Churchward GWR locomotives and have some engineering experience and, contemplating early retirement, this seems an ideal opportunity to go for it. Why does that trigger this thread you may ask. I am trying to find out which of the boiler options I can consider. Five different boiler types were used on locomotives of the class, six if you include superheating, and so my question is how many of those have approved drawings. It is potentially only one, the one used on Keith Wilson's Dukedog. The Bulldog, City and Dean Goods boilers that I am aware of would not be appropriate. Am I missing something that I should also assess? I haven't got the expertise to design and build a boiler so want use one for which approved drawings already exist and would look to get it made.