909 Naperville Road, Wheaton, Illinois 60187.
A 2/5 Scale Model Advance Steam Traction Engine Built in 1961 by
the Owner, Ross Naylor, Box 111, Platt City, Mo. It is his No. 1
Boiler description; Locomotive dry bottom firebox type, shell
15’Dia. 60′ long, seamless, 141′ tubes 32′ long,
firebox 12′ wide, 15′ long, 14′ grate to crown sheet.
Boiler hydrostatic tested to 225 lbs. design steam pressure 150
lbs. and operating pressure 150 lbs. Heating surface 23 Sq. Ft.,
Grate surface 1.3 Sq. Ft., furnace volume 1.51 Cu. Ft. The boiler
will produce, when burning 46 lbs. of dry wood per hour having 8500
Btu. per lb. with 60°F. feed water temperature, 150 lbs. steam
pressure at 68% boiler efficiency, 228 lbs. of steam per hour.
Engine description; a single cylinder simple, 4′ bore,
5′ stroke, ‘D’ slide valve, Marsh valve gear and
reverse with cutoff at 6/10 stroke, 225 RPM. on governor control on
belt or traction work. At 101.3 psig., (lbs. per sq. in.) MEP. and
225 RPM. the engine will produce 71 HP., (indicated horse power).
At the same conditions with 79.9% engine mechanical efficiency it
will develop 5.6/H. P. at the flywheel rim.
The engine traction system is a two shoe band or flywheel
clutch, a 22 tooth crankshaft pinion, a 68 tooth intermediate gear,
a 68 tooth differential spur gear, 12 tooth countershaft pinions,
80 tooth bull gears, and 2′-6′ Dia., by 9′ rim drive
wheels. The engine with fuel and water supply weighs 2,000 lbs. The
ratio of engine RPM. to drive wheel RPM. is 10.92 to 1. The road
traction speed at 225 Rpm. engine speed is 0.975 MPH. The horse
power delivered to the drive wheels is 2.9 equal to a gross
tractive effort of 1,115 lbs. The net drawbar horsepower when the
engine is traveling at 0.975 MPH., on a light clay stubble field is
807 lbs., equal to 2.1 horse power.
Engine construction features through the courtesy of Mr. Ross.
Engine performance calculations by Ernest H. Casson.