Really a very neat little engine, good job!
One of the visuals for spotting a coal burner is the space given the smokebox, just in front of the stack. Coal burners were given an "extension" here either as an addition or part of the initial design for coal that accommodated a damper and netting arrangement, not usually present in wood burners. On those ash control was in the larger, or "balloon" stack of the day. Control of draft and firebox/ grate features are different for different kinds of fuel. Your engine has that space, and would be to my eye a coal burner. It WAS common in the transistion era (yes, there have been several!) from wood to coal ...about 1875 more or less, to apply a "diamond stack" to catch cinders and fly ash depending on how the firebox was designed and the grade of coal, to engines that had formerly been wood burners. If the engine lasted into the turn of the century, by then the front end would have been of modern design and the smokestack converted to straight. There would have probably been also other modern improvement to the engine the later it served. Electric lights came into regular service on the NC&StL and other Southern RRs about 1920-25 for instance.

All that said, its your engine, you choose!

Tom Knowles
NOTE NEW ADDRESS:  tomk@...

On 7/13/2013 7:43 AM, nvrr49@... wrote: