This is an ash pan from a Doble Steam Car, and it fits underneath the boiler. The original (shown in foreground) was too rough to use, so a new one was worked up using the TM Air Power Hammer with a little planishing on the English Wheel.

The dome itself (including the flange) is 36″ in diameter, and is made of ONE piece. It raises 5.5″ at the center.

The “tube” is added, as are the clearance blisters around the edge. It is gas welded. Too bad the customer wouldn't bring in the boiler for me to fit  too.