Smokebox pieces machined up ready for setting up to index rivet holes.
Smokebox rolled from 5mm plate. (I like heavier material for traction engine smokeboxes Drawing calls for 2mm, bit I prefer to roll up heavier plate and counterbore to look scale thickness on front end around door ring.)
Joint ring rolled from 10mm plate and machined circular to suit OD of boiler and ID of smokebox
Smokebox door ring machined from casting
(faced up true and OD machined to suit counterbore in smokebox, then radius machined with profile tool)
To the dividing head next to index the rivet holes and machine chimney hole profile. (chimney saddle and perch bracket will be machined up first to allow clamping up and mounting holes to be drilled to correct coordinates and angular index)
