Instructions - Step

The Midwest Model VI Steam Engine Kit is the heart of this locomotive. The instructions provided with the kit are thorough and easy to follow. The most important part of the assembly is the port face of the cylinder. Make sure you do not scratch it or “round over” the face by sanding it. Instead, you can burnish the face

Figure 1

on a piece of brown paper (from a grocery bag) on a hard, flat surface. Assemble the boiler and engine as directed by the Midwest instruction manual. The screw that holds the port block to the cylinder should be given a drop of Loctite. It will be adjusted during the first run for optimum performance. In some cases it may be necessary to remove ½ to 1-1/2 coils from the spring. Too much spring pressure will cause excessive drag and may even prevent the engine from running.

The remaining 7-tooth sprocket “V2” mounts on the output shaft of the motor (Fig. 1). As with the other 7-tooth sprocket, the set screw may need to be shortened. The motor mounts to the deck with four 3/8” long, #2 brass wood screws (Fig. 2). The mounting holes in the motor base can be elongated with a round needle file to provide some fore-aft adjustment. The holes should be marked with the motor in place and the slack pulled out of the chain (Fig. 3). However, the chain should not be taught. Don’t forget to drill 1/16" diameter pilot holes before driving in the screws.

Figure 2

Use care when aligning the motor on the deck. The sprockets should be
aligned with each other and the chain should not "bend" to either side.

Figure 3

As supplied, the lubricator does not have any provision for mounting. You can use a 1” long piece of the ¼” x .032” brass strip and soft solder it to the bottom of the lubricator (Fig. 4). It’s easier to drill the 1/8” diameter mounting holes in the bracket before attaching it to the lubricator. Don’t forget to remove the O-rings from the fill and drain plugs prior to soldering. Drill the mounting holes for the lubricator in the deck using a 3/32” drill bit. Secure it with two, ¼” long, 2-56 machine screws and nuts (Fig. 5).

Figure 4

Figure 5

The lubricator is an important accessory. It helps to keep the motor from wearing out prematurely and adds considerably to the power of the locomotive. Without a lubricator, much of the steam is wasted as it leaks past the piston and escapes to the atmosphere. This leakage is known as "blow-by". The lubricator mixes oil with the steam thereby providing a seal between the piston and cylinder wall.

Locate the fuel pan from the Midwest kit on the deck. Note that the pan is centered left to right, but is placed slightly towards the front of the deck (towards the bunker end). This is to make sure the boiler will clear the large sprocket of the geartrain. Mark the locations of the three 1/16” diameter positioning pins (again, from the Midwest kit) and drill the 1/16" diameter holes through the deck.and into the crossbraces. Roughen the ends of the pins with coarse sandpaper and use epoxy to secure them in the holes. The pan is not glued so that it may be removed for fueling and cleaning.

The boiler wrapper needs to have additional holes punched in it to allow enough air into the fire. Using an inexpensive paper hole punch from the stationary store, double the number of holes in the firebox area of the boiler wrapper. Assemble the boiler per the plans provided with the Midwest kit. Next, place the assembled boiler over the fuel pan and its locating pins. Cut the silicone tubing steam lines “AD” so that they make a nice gentle curve from the boiler to the lubricator , and then on to the motor. You must slide the hose clamps “AC” over the steam lines before attaching them to their final locations. This concludes the installation of the powerplant.

This page last updated: 12/10/03