Building a Portable Steam Farm Engine

When my friend Shawn asked me about a model of a steam engine to power his sawmill, he was thinking of a traction engine. My response to him was that a portable would be easier to construct - no gearing, no steering parts, no bunkers... Just a boiler, wheels, and engine -simple, businesslike, and clean. Contrary to how it may seem today, portables were built longer and in greater numbers than traction engines. They were moved from job to job with a team of horses, and could be found working just about anywhere belt power was needed - in agriculture, mining, and, yes, even sawmills.

But what kind should we model? There were dozens of brands; Case, Russell, Frick, Farquhar, Port Huron, Aultman-Taylor, Advance, etc., etc. I eventually decided on the Robert Bell, built in Seaforth, Ontario. My main criteria in choosing this make were that it is simple- with almost generic styling, yet attractive, and the ability to use many 'off the shelf' parts for those who lack more advanced building skills

The Robert Bell
Some of the following images are larger than they appear





For those who like to be different, some were built with the engine reversed!


Not a bell, but this pic shows a typical set-up with a feedwater barrel and the diagonal wheel chocks that kept the engine from rocking itself into a hole

What you'll need:
1/2" or 5/8" diameter tube for cylinder and crosshead guilde
1" or 1-1/4" pvc pipe (nominal, +/- 1-1/2" actual) for boiler
fairly stiff sheet styrene to make firebox, etc
4 spoked wheels
1 spoked flywheel (1-1/2" - 2" (36"-42") depending on scale, with about 1/2" face)
various diameter wire and tube for axles, crankshaft, piping

Ozark Miniatures also has the following castings that will make this project easier;
#15 Disconnect Journal (Lamoine) - for main engine bearings (4 in package, you need 2)
#24 1/2" nwb castings - bolt detail
#27 1" nwb castings - large bolt detail (optional)
#74 poker and rake (optional)
#75 tallow pot and hammer (optional)
#167 Loco Stack  (optional)
#170 Sm Safety Valve (2 in pack, you need 1)
#172 Domed Whistle
#185 Pressure gauge (3 in pack, you need 1)
#188 Water Gauge and trycocks
#235 Cannon Wheels  -front wheels
#1092 Cannon wheels  - rear wheels
#5008 firebox door square
#5027 33" flywheel 
Of course if you buy all the above, you'll have over $45 just in casting parts. So if you can scrounge, fabricate, or decide to do without any of the above it will save you money!

To Be Continued....