Boiler tubing

	Photo added 1/8/2003 Chasing out the firebox tubeplate threads to ensure they are in top condition before fitting the flue tubes.
	One of the (35) bottle-ends after thread cutting and internal boring. A total of five different thread diameters were required due to very slight differences in the firebox tubeplate threaded hole diameters. After completion, all 35 bottle-ends were welded to the relevant flue tubes by a coded welder.
	Jig used to line up exactly the bottle-end to the flue tube. Concentricity was vital for the later operation of screwing the flues into position.
	Three temporary spacing bars were then tack welded to the bottle-end and flue and the jig removed. The gap was then welded as per requirements and the temporary bars removed.
	After welding the joint was ground down to the tube diameter and inspected.
	Starting to install the small tubes. The metal ring on the end of one tube is a gauge to ensure the correct amount of tube is proud of the tubeplate for beading over.
	Installing the flue tubes. To ensure that the threaded 'bottle ends' on the flue tubes lined up exactly with the firebox tubeplate threads, a special tool was made. This tool screwed into the tubeplate from the firebox side, the flue was pushed in from the smokebox tubeplate along a guide rod......
	......and over the tool, the threads were lined up, and then the flue and tool were rotated together. Thus, as the tool unscrewed from the tubeplate, it guided the flue tube thread accurately into place.
	Lining up tool in place to accept the last of the flue tubes. Note the 'lip' left on the flue tubes ready for beading over after they are expanded into place.
	Air powered beading tool used to bead over small and flue tube ends.
	Firebox tubeplate after all small tubes (138) and flue tubes (35) have been fitted, expanded into place and beaded over.
	Inside the firebox looking toward the firehole door. The rear fusible plug can be seen between the rows of roof stays. All of the stay nuts in the firebox (fitted to protect the stays from the heat of the fire) were made by the group.