The builder had an "oh b*gger" moment when machining a hole in the top of the boiler barrel - it looks like the cutter picked up and gouged metal around the hole. A patch plate has been made to be soldered over - it will be concealed under the cladding when finished.
Both this engine and the 7 1/4 inch gauge "Locomotion" came from the estate of an award-winning model engineer who specialised in early locomotives and stationary engines.
Locomotive 29 inches
Tender 18 inches