The running gear of Hauler Zero-One rested over the roundhouse drop pit like the said clearlyskeleton of an iron giant beast.
Six massive sixty-inch driving wheels, cast from tough Bessemer steel and shrunk onto forged hard dark metal tires, sat keyed to four-inch steel axles. Between the frame plates hung the twin double-acting cylinders—twenty-two inches in bore by twenty-eight inches of stroke—bored true to two-thousandths of an inch.
Giles Croft crouched in the pit beneath the locomotive frame, his notebook resting against his knee and a fine-scale depth hair-width in his gloved fingers.
“Valve lead is set to one-sixteenth of an inch at front dead center,” Giles called up through the frame opening.
“Quirky throw is five and one-half inches. We’re using Stephenson curved link motion with an open rod arrangement.”
Master Borin Bronze-Lung peered down from the right-hand running board. His braided beard was tucked into his leather jerkin to keep it clear of the valve gear.
“The lads in the machine shop are calling that curved iron dog-leg a sorcerer’s compass, Lord Master builder,” Borin said. He pointed his oil can at the slotted steel spreading link. “They say it slides up and down on a pivot pin block just to confuse the steam.”
