75. Engine Sprocket
76. Primary Chain
77. Secondary Drive Sprocket
78. Doubler, 1/2" plywood
79. Full size plywood spacer
80. Primary driven sprocket
81. #35 final drive chain
82. Ball bearing saw arbor
83, 84. Slots to permit chains to pass through floor. Dimensions to suit your particular installation (engine crank height, etc.).
85. Center lines of 82 and hinge pins must coincide, adjust thickness of 79 to suit.
82. is fastened to 78.
Make chain guards to suit.
Make all fastenings with screws and bolts.

Now, we will discuss the type of engine which would be suitable for use in the EDUCATOR. We must keep the cost to a minimum in order to meet our quoted cost of $495.00 for the entire vehicle. To do this we must choose a low cost item and do most of the work on it ourselves to keep the money 'in the family' so to speak.

For those who wish to machine from ready-made castings, it is suggested that the Stuart Turner casting sets be purchased. The size engine that is recommended is the No. 1 with bore and stroke of  2"x 2". In order to have a self starting engine of adequate power, you will need two engines and couple them together with a chain or sleeve. Both engines being mounted on a common base.

It is further suggested that the engines be enclosed in a dust tight compartment with the drive shaft protruding far enough to permit the mounting of a drive sprocket by which to drive the jack-shaft shown in a previous issue. The enclosure should be of sheet metal with a door conveniently located for inspection and oiling as many people will want to see the 'workings’.

As a minimum engine, it is suggested that the Stuart No. 4 or 9 be used. It should be remembered that the labor involved in building a pair of these engines is almost exactly the same as that required to build a pair of the larger and recommended engines, therefore we strongly I urge you to consider only the 2"x 2" size.

The Stuart Turner engines in kit or completed form may be purchased from Cole's Steam Models, Ventura, California.

For those who would prefer to convert existing IC engines such as a Briggs & Stratton to steam, it is suggested that possibly, in your area you can find a pair of old lawn-mower engines that could serve as the basic power plant. Often, these can be had for a little more than the effort required to haul them away. You will not need the fuel system or the exhaust pipe or the head. Just be sure that you get two of the same model. These old cylinders will serve as the crosshead guides for a double-acting engine. Stuart No. 1 cylinders can be used as the steam cylinders. This arrangement will cut down on the amount of machine work required.

This is beginning to get disgusting. We ordered the burner assembly from Montgomery Ward some time ago and just received a notice that they will not even ship it until the 20th of January. In that we do not have the burner and thus are not aware of its flame pattern, we cannot properly proportion the combustion chamber space. We have, however, determined the amount of materials required to build the steam generator. Those who are building this generator are advised to obtain the following:

200' of 1/4" O. D. copper tubing - standard grade - . 031 wall
25' of 5/16" O. D. copper tubing - standard grade - . 031 wall
2-1/2’ of 5/16" O. D. stainless steel - 300 series - . 020 to . 035 wall (a straight section)
1 sq. yd. of heavy duty high temperature insulating fabric (Cerrofelt)
1 – 3’ x 4’ sheet of 26 gauge steel. It may be blued, nickeled, Stainless or just plain black iron.
50' (approx. ) of . 050 (approx. ) stainless steel wire – 300 series.
1 weed burner - 2 gal. size - (see Montgomery Ward farm Catalog No. 89FB21282MS)

The underside of the EDUCATOR and the arrangement of the jack-shaft/chain drive from the engine to the axle.

And how to build it from shelf ready parts.

This is not the best way to fire a boiler, but it is easy to control, and is fairly cheap. Its major fault is that it takes longer to start the burner than it takes to raise steam. Also, it is somewhat noisy.

When your 89FB21282MS Ward's "Flamethrower" (weed burner) arrives it will be partly disassembled. Instead of putting it together, we are going to further take it apart and make some alterations. First, remove the sheet metal hood by removing four screws. Remove the burner nozzle and carefully enlarge the nozzle orifice, using a .060 drill This should be done in a lathe to ensure straightness. Now, re-install the nozzle tip. Remove two small screws and nuts from the bracket and withdraw (endwise), the nozzle assembly, spreading the bracket open only as necessary. Heat and bend the fuel inlet tube as shown in the picture. Take care to avoid kinking the tubing. Re-install the assembly as shown, tightening the bracket screws securely. Cut a slot in the, side of the hood to accommodate a "Turner" heavy duty burner tip, #LP-242 (or equivalent), leaving a "tab or tongue". Install "Turner" pilot as a pre-heater burner in the slot and attach it to the tongue with a small gear-type hose clamp. Aim the pilot burner so that the flame will play on the far side (inside) of the main generator coil. Obtain a "Turner" (or equivalent) 'torch' which will supply us with a pilot valve and pilot burner, etc. Detach the supply tube from the valve and install the 5/16 compression union in its place. Install 2 1/2 feet of 5/16" copper tube to the other end of the union. Connect the free end of the copper tube to the valve, using the fitting supplied with the torch.

Several experiments were undertaken to adapt the weed burner to our use. In its final form it delivered the following results: With pilot on full, the main burner generated in 2 1/2 minutes and was capable of burning 6. 1 pounds of fuel per hour. (Diesel fuel= 115, 000 btu/pound). At the recommended 25 psi fuel pressure, this should give us approx. 5 hp. nominal.

The fuel system was based on a two-tank Coleman style Army field kitchen vaporizing burner. The little gage panel is from that also. One tank holds white gas, filled through a floorboard cutout. The other is filled with air from the filler valve on the little panel.

As a prelude to describing the steps to take in the construction of the steam generator for the EDUCATOR, I would like to point out that this particular design is not necessarily the only design to use in this vehicle, but it is the simplest and easiest for the neophyte to construct and build controls for. Several years of experimentation have preceded the selection of this design for this particular application It should be remembered at this time that for a larger unit, say, for a full sized automobile, this is NOT the design to use. This device car be constructed with a minimum of tools and know-how, and will work very well. We know, because we have tested this design extensively.

You may now refer to the step by step pictures. In photo #l. coils "a, d & e" were wound of 1/4" O. D. copper tubing over a 5" dia. form. In this case, a gallon paint can was used.) Coil "d" was necked down to 3 1/2" I.D. at one end by hand. Coil "b" is a flat pancake type of coil would by hand to fit inside a space 5 1/2" by 11 1/2". Coil "c" is the hard one to make. It is suggested that you tape two paint cans together, side by side, and form the tubing around then as shown. It may be a little difficult to form the reverse bends but care must be exercised to prevent flattening of the tube in the small radius area. As you proceed. these radii become larger and there-fore easier, please do watch the direction of winding in all coils. You will want all connections to be in the correct position when you have finished the coil winding. Coil "f" was formed as a series of flat pancakes by winding the tubing against itself, all coils touching, and then opened out as shown to leave gas passage spaces between the coils. This is your economizer section.

Photo #2 shows all of the coil sections in position for assembly.

Photo #3 shows coils "b" and "c" assembled. Please note the connection and lay of the tubing.

Photo #4 shows all sections joined by bell & spigot joints, brazed. Drive a 1/4" dia. dowel pin into one tube end and this makes the bell. The other tube will slip in for a fine brazing joint. All sections are now tied together as shown, using 1/8" dia. 300 series stainless welding rod and .050" stainless steel wire. Don't be stingy with the ties. You will note that the welding rods form a cage and the small wire is used as ties across the diameters of the coils. This prevents the coils from expanding like a Bourdon tube in a pressure gauge.

Photo #5 shows the inner covers in place. The author used bright stovepipe steel (tinned). A generous wad of asbestos fiber was stuffed into the "crotch" area to prevent the escape of hot gases.  Then section "b" was covered with asbestos cloth and sheet steel.

Photo #6 shows the completed steam generator with asbestos and steel covering the hot end. Our straight section of 5/16" stainless steel tubing is connected to section "c" by bell and spigot joint AFTER passing the tube through the combustion chamber. (Note: The stainless to copper connection should protrude 3" beyond the hot end of the generator for later control connections. )

To review the flow path of the water and steam through the various coil sections, just to be sure that you get them right the first time. The water goes in at the left end of ."f". From right end of "f" to the left end of "d". From the right end of "d" to the left end of "a". From the right end of "a" to the left end of "e". From the right end of "e" to the outer end of "b". From the inner end of "b to the left end of "c". From the right end of "c" to the straight piece of the stainless "steam Outlet". Be sure to leave the 3" protrusion for later control connections.

Control System Diagram

Control System Linkage

Water System Diagram

Fuel System Diagram

Primary Control Valve. Three required.
1. 1/8"dia. brass rod, groove as shown, and mill flats on one end to fit slot in ball.
2, 6, 9. Teflon seals, machine to fit.
3. Gland nut, 5/16 hex brass. 1/4-40 EF thread (as used on miniature toggle switches.
4. Stem guide, 1/4" dia. brass. Press fit to body.
5. Body, 5/8" hex brass, ream 3/8" dia. through.
7, 10. Adapter bushings, drill through 3/16", press fit to body, drill and tap to suit pipe work.
8. 3/8" dia bronze ball. Ream 3/16 through, slot to receive stem.

This valve has been tested in service for several years and is a proven design, for pressures to 500 psig and 400F.

At one time this valve could be obtained from Cole's Power Models, P.O. Box 788, Ventura, California.

Differential Pressure Flow Control Valve.
1. Outlet, feed to steam generator.
2. Diaphragm, elastomer impregnated fabric, such as used in propane regulators.
3. 1/8" dia. flow passage (two places)
4. Inlet port from feed pump.
5. 1/8" brass nipple, plug, drill and ream 3/32" dia.
6. Drill and tap body for six #6-32 socket head cap screws as shown.
7. Bypass outlet, may be used to control pump output.
8. Body, 1 3/4" hex brass, machine as shown.
9. Outlet to primary water control valve.
10. Metering pin, 302 stainless steel, 3/32" dia. body x 1" long, 5/16" dia. head, 1/31" thick, close slip fit to 7. Make "v" notch end as shown.
11. Saddle, form of 1/32" brass, braze to lower diaphragm plate, provide loose fit for head of metering pin.
12. Upper diaphragm plate. Plates are formed of 1/32" brass to 1 1/16" diameter. Flare edges to protect diaphragm. Lower plate is furnished with #6-32 stud for fastening to upper plate through diaphragm. Light (2 to 6 oz.) stainless steel spring loads the diaphragm downward. Diaphragm requires 1/4" free travel.
13. Inlet from primary water control valve.
14. Ports (6) are all 1/8-27NPT.
15. Surge damping screw, may be left open or partly closed to prevent pulsation. Screw is threaded #12-24 and is provided with screwdriver slot.
16. 1/8" brass nipple, drill and tap #12-24.
17. 1/8" brass pipe cap.

Throttle Valve

1. Stainless steel (302) stem. Machine thrust collar as shown and mill flats on end to engage ball.
2. Teflon thrust washer.
3. Teflon stem packing.
4. Lock nut.
5. Standard 5/16" flare fittings altered as shown.
6. Lock nut. Chamfer as shown for seal 14.
7. Stem guide, 1/4-10 thread full length.
8. 5/8 hex body.
9. 3/16" dia. hole.
10. Body is threaded 7/16-32 through. 3/8" dia. ball. Mill slot as shown to suit stem.
11. Floating seal.
12. Body is threaded 7/16-32 through.
13. Thrust nut
14. Lock nut to body seal (Teflon).
Note: Ball to seal clearance .002 +.001

All parts are brass or bronze unless otherwise noted. Workmanship must be first class on parts 1-5, 10 and 11 or the valve will leak. Parts 5-10 and 11 must match to very close limits.

This valve has proven itself over several years use in temperatures from -256F to over 950F and with pressures up to 10,000 psi.

1. Check valves, "Circle Seal" 2259B, 1mm is recommended for pressures up to 250 p.s.i. #23498-1mm is recommended for higher pressures, soft rubber or plastic hose is recommended for inlet connection

Using the burner described in a previous installment in this series, a certified scale for weighing the water, a pressure gauge a stop watch and a variable displacement pump, the following data were obtained:

After the burner was started; first steam from water at 68F was made in approximately five seconds.

Operating pressure= 225 psig (mean)
Operating temperature (steam)= 400F.
Evaporation rate= 80 pounds/hour.
Stack temperature= 200-250F.
Fuel used= Cleaning solvent.
Date of test= 3/29/66
Test Engineer= R. J. Smith.
(Water was mixed with 1% soluble oil. )

These two pictures are pretty well self explanatory except to say that they show the only manual controls to worry about on the EDUCATOR. The air and fuel valves are adjusted only at the start and end of your trip, and then all you have to do is turn them on or off. The steam gage is for reference only. It need not be on the dash board.

This picture shows the arrangement of the engine, fuel filler and the hand pump that was put on the car before a power operated pump became available.

This picture is for information only and shows how the rug is fitted around the pedals and steering tiller in the prototype EDUCATOR.

This pair of pictures show the EDUCATOR as it looks when finished. It is a pretty slick appearing buggy. It is ideal as a second car to run to the store or take the kids to school in. Whereever it is driven it is a traffic stopper. Every one asks what it is, how it runs, how fast will it go, how many mpg, and what kind of fuel. The really important question is, where can I get one? When people are told that it is home built, they won't believe it! The prototype is painted a candy-apple-red and is truly beautiful. When it takes off, people are amazed at the great pick-up and the silence. This unit being non-condensing, there is a little noise but if a condenser were added it would be perfectly silent as an electric car.

Karl gives a visitor a ride in the alley. Dick walks behind.                Karl Petersen demonstrates at the Laguna Beach meet.

Richard J. Smith shows off the completed chassis.

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