Toy Steam Shovel

I wanted to make a working toy steam shovel for my grandson's fourth birthday. It is a companion piece to the circa 1920 Mack AC Bulldog toy truck I made for his third birthday. I did a series of Instructables on how the truck was made. (Each Instuctable in the set is linked at the end of the previous one.)

Materials

• 1/8 inch steel rod
• 3/16 inch steel rod
• 1/4 inch steel rod
• 3/8 inch steel rod
• 1/2 inch steel tubing
• 3/4 inch square tubing
• 1/8 x 1/2 inch bar steel
• 1/8 x 3/4 inch bar steel
• 1/4 inch thickness flat steel
• 1/2 inch steel angle iron
• 20 gauge steel sheet
• Various washers
• Flat head screws, nuts, and lockwashers (for roof)
• 6 x 32 screw about 3 inches long (for attaching the smokestack and faux boiler to the roof)
• 1/4 inch steel bearing balls
• 1/4 inch bolt and nylon locking nut
• 50 pound test monofilament fishing line
• Copper tubing and wooden dowel (for the onboard whistle)
• Paper for patterns

Tools

• Flux core wire welder
• 4 inch angle head grinder, grinding wheel, cutter wheel
• Drill press and bits
• Handheld electric drill
• Vise for drill press
• 1/2 inch Jacobs chuck on a radial arm saw
• Bandsaw
• Various clamps
• MAPP gas torch for soldering
• Dremel tool and grinding bits
• Flux core Solder
• Scissors
• Draughtsman's compass

Some very early steam shovels had wheels rather than crawler tracks. Toy steam shovels from the 1920s also had wheels.

I found some 1 inch steel pipe on the curb waiting for garbage pickup. (First photo) I cut it in 1 inch lengths for each wheel. I wanted to make the wheels a bit fancy with contours and a hub. (Sixth photo) I placed one of the 1/4 inch bearing balls for the engine house swivel into the hole in a 1/4 inch fender washer, placed the fender washer over an end of the a wheel tube, placed the assembly in a vise, and tightened the jaws to distort fender washer.

See the second photo. I used a short 1/4 inch machine screw and nut to chuck the washer in a drill. I held the spinning washer against a spinning grinding wheel to reduce the outer diameter of the washer until it just slipped inside pipe for the wheel. I tack welded the fender washer from behind inside the wheel. I also ground the end of a 3/8 inch steel rod to make a hemisphere. I cut it off and dropped it into the hole in the washer to make a center hub as seen in the sixth photo. I also tack welded it in place.

See the third photo. I placed a piece of 1/8 x 3/4 inch bar into the vise for a drill press. I positioned a piece of 1/4 inch rod into the chuck of a drill press and welded the rod to the bar.

See the fourth photo. I made a mandrel with 3/16 inch rod to hold the bar so I could spin it and make the ends rounded so they would fit inside the back end of the wheel. I used the rotation of the grinder so the retaining nut on the mandrel tended to tighten, rather than loosen.

See the fifth photo. The 1/4 inch rod is back in the drill press chuck. The rounded ends just fit inside the wheel. The chuck and vise hold them in alignment. I welded the bar inside the tube that is the wheel. I chucked the 1/4 inch axle in the chuck on the end of the radial arm saw and gently held a grinder to its outer surface to make certain it is concentric with the 1/4 inch axle. See the sixth photo again. I also ground to smooth rough spots where the washer meets the steel tube wheel and to round the front corner on the wheels.

See the first photo. I used 3/4 inch square tubing to make a carriage framework for the wheels. I welded squares of steel over the open ends of the square tubing. Notice the 1/8 inch bar across the open space between the cross members. The pivot bolt will be positioned in it. The cross members were placed so the circular track for the bearing balls in the fourth photo is always over the square tubing and supported by it. In the fifth photo the wheel axles have been trimmed and retainers added.

I covered the open area with sheet steel. See the second photo.

See the third photo. I welded a "spider" together. It is to hold the bearing balls on a concentric track. I made a pivot point in a 2 x 4 so holes would be drilled equidistant from the center. The fourth photo shows the spider on its pivot bolt. I placed three 1/4 inch fender washers on the center bolt below the spider and two above it to keep its elevation centered on the bearing balls. Some photos show a wing nut I used temporarily until I was ready to put the nylon insert locking nut in place and leave it there.

See the fifth photo. I began the upper part of the swivel, which is also the bottom floor of the engine house. It is a piece of 1/16 inch steel plate welded to 1/2 inch angle iron pieces. I used a nylon locking nut and adjusted the tension so the toy shovel will swivel smoothly, but not be loose or sloppy.

The booms on steam shovels were most often from solid plate. I decided a boom with open bracing would better fit the image in my mind. I made a boom from 1/8 inch rod bent and welded to straight pieces of 1/8 inch rod. Careful as I tried to be, the heat from welding caused some distortion and I had to do what I could to remove slight bowing in the finished boom.

See the first photo. I put 1/8 inch rod in a vise and made right angle bends to form a zig-zag stair step pattern. See the second photo. I have a piece of aluminum angle I used to hold the pieces of the boom for welding. I planned the welding so the welds would be inside the boom and not visible on the outside of the boom. That meant welding the fourth side to the boom meant inserting the welder tip through the open spaces on other sides to make a weld. This worked fairly well with the thin end of a flux core welding gun, but would have been very difficult with the shorter stick out and fatter nozzle on a MIG welder.

See the third photo. I welded 1/8 inch steel on two sides of one end of the boom and drilled them for an axle to hold the pulley that lifts the bucket.

The fourth photo shows the boom attachment at the front of the engine house. I wanted to be certain the boom was centered and moved up and down without any deflection or caster. After welding a pivot pin across the rear end of the boom and making sure it was aligned properly, I used 1/8 x 1/2 inch steel bar to make tabs for mounts. I clamped everything to my aluminum angle to make certain it was all properly aligned before welding. (See the fifth photo.)

Steam shovels were able to raise and lower the bucket by shortening or lengthening the distance between the boom and the bucket by means of a separate steam engine on the boom and a gear wheel. The two vertical beams are called dipper sticks. That is the official nomenclature. On my toy version, the dipper sticks do not rise or lower, but the bucket can be raised in an arc about an axle near the middle of the boom.

The bucket is from an old piece of 1 1/2 square tubing. See the first photo. I cut it on a diagonal for the front of the bucket. I cut it off square for the back of the bucket.

The second photo shows the setup I used to align the bucket and the boom while welding the dipper sticks to the bucket. I wanted the bucket to be flat on the ground, not cocked to one side or high on one side. Notice, too, that I welded some 1/8 inch flat steel on both sides of the boom in open spaces so I could mount an axle for the dipper sticks.

The bucket on a steam shovel is hinged to open toward the back. On a toy steam shovel there needs to be a way for gravity to close and secure the hinged back of the bucket. It also needs to release easily. Steam shovels used a rope the operator pulls to release the back of the bucket. See the third photo. I used a system I saw illustrated in an advertising brochure for a 1925 toy steam shovel made by Structo. It involves a sleeve that slides on one of the dipper sticks. Connected to it is a claw that holds the back of the bucket in place and slides into place by the force of gravity.

I had some flat steel about 1/4 inch thick. I wanted to make a pulley for the end of the boom. I cut a square from the steel and drilled a hole in its center for the little mandrel I mentioned in step 2. Then I used a grinder with a cutting wheel to make round blank for the pulley.

The second photo shows the finished pulley. I attached it to the end of the boom with an axle and used spacers to keep it centered.

The third photo shows the pulley mounted on the end of the boom. I also added a fender washer on the axle for the dipper sticks to simulate the gear wheel that would raise and lower the dipper sticks.

I wanted the back of the shovel to be rounded with a radius from the swivel bolt at the center of the engine house. See the first photo. I marked and cut a piece of 1/8 x 3/4 inch bar, grinding it to fit the radius, and I welded it in place on the floor of the engine house at the back. I welded two verticals to the back of the engine house using 1/8 x 1/2 inch bar. I bent and welded a piece of 3/16 inch rod between the two uprights. Then I fitted, cut, and welded the back of the engine house from sheet steel.

Steam shovels had a steam whistle. See the second photo. I once did an Instructable on using plastic soda straws to make a child's whistle. I used what I described there to make a whistle from brass and copper tubing. This whistle uses a plunger in a larger tube to push enough air through the whistle so it can be heard. The plunger is a piece of 3/4 inch wooden dowel. I cut a couple of felt discs for a seal and attached them to the inner end of the dowel with a screw and washer. Compressed, the whistle fits between the sides of the engine house when not in use. (I flattened some of the copper tubing and soldered it to the back end of the whistle to seal it.) The whistle was mounted on a mount I made for it with 1/2 inch angle welded on top of a piece of 3/4 inch flat bar. I left a slotted space so I could clamp the whistle to the mount with an automotive hose clamp. I did spray the copper and brass with clear enamel to keep it bright.(Later I made a slot in much of the length of the dowel and allowed a point of copper wire to come through a hole in the copper tubing so the plunger cannot be pulled out of the whistle and lost.)

There is a hand operated windlass for raising or lowering the angle of the boom, and a similar windlass for raising and lowering the bucket. Each windlass has a shaft made of 1/4 inch rod. On it are two washers welded to the ends of a short piece of 1/2 inch electrical metallic tubing (conduit). One windlass is cranked from the right side of the steam shovel and the other from the left side. The first photo shows the windlasses partially finished and welded in place. The cranks and the catches are not yet installed.

For illustration purposes, I fashioned a wooden model to show how each windlass is made and works. The second photo represents a piece of 1/8 x 1/2 steel bar about 1 1/4 inches long. (I would have liked longer cranks, but the cranks had to fit under the engine house roof when turned.) Welded to the 1/8 x 1/2 inch bar is a short piece of 3/8 inch rod.

The third photo shows a 3/16 inch hole drilled through the center of the rod and the bar. Another hole has been drilled at the other end and a 1/4 inch windlass axle has been welded into it. The piece of dowel represents a 3/16 inch locking pin that slides inside the 3/8 inch rod. (On the actual toy steam shovel, there are stops to keep the rod from sliding too far in either direction. There is also a bit of a knob for easier grasping of the sliding rods.)

The fourth photo shows a model of the assembled windlass, minus some inconsequential details not needed for this illustration. A piece of larger dowel has been added to represent the drum on the windlass. The sliding pin is in place in the locked position. The bearing piece for the windlass axle also provides a surface against which the locking pin can keep the windlass from unwinding. (I actually made a spider with six arms so the position of the bucket and the dipper sticks can be locked in any of six positions, but the other arms radiating from the center axle area are not shown here.)

The fifth photo shows the locking pin pulled outward from the windlass so the windlass is unlocked and can be turned.

I added a support from 3/16 inch rod for the front of the roof. (See the first photo in the previous step.) I welded 1/8 x 1/2 steel bar between the front and rear roof supports on both left and right sides. The 1/8 x 1/2 bar is drilled and countersunk near the front and the back so flat head mounting screws would be flush with the surface of the roof.

Photos of old steam shovels often show part of the boiler rising above the engine house roof with a smokestack on top of the boiler. See the first photo. This step will show how I made the faux boiler and fitted it to a curved roof. It is not difficult if done in logical steps. (I did not take photos while I actually made the faux boiler and will illustrate the process using paper rather than sheet metal.)

See the second photo. I cut a piece of 2 x 4 to make a square. I marked the center and used a compass to inscribe a circle the diameter of the boiler.

See the third photo. I am using a paint can to represent the curvature of the engine house roof. I drew the arc of the paint can (or roof) onto the end of the square block. When I made the steam shovel, I drew the contour of the engine house roof, not a paint can.

See the fourth photo. Use a bandsaw to cut along the arc line. Be certain the wood does not tip. A 90 degree support for use during sawing would be helpful.

See the fifth photo. With both pieces of the square block held together, follow the circle with the bandsaw.

See the sixth photo. Tape a strip of paper around what is left of the wood block and mark the contour of the wood one the paper. You can cut to follow the line and use this as a paper pattern. Or, you may use a strip of sheet steel in place of the paper. Mark it and cut it. Hold it around the wooden block profile and tack weld its ends together. Trim with a grinder bit on a Dremel tool. Check the fit on the actual engine house roof and grind as necessary.

See the seventh photo. Test the fit of the wood template on the engine house roof. (in this case, the paint can model) The eighth photo shows the paper pattern (or the actual sheet steel band) on the roof for a test fit.

See the ninth (final) photo. To make the conical top of the boiler, I drew a circle on sheet steel and made the circle a little larger than the boiler diameter. Then I cut to the center of the circle from the edge and pulled side of the cut over the other to make the cone I wanted. (Blue tape holds the paper in a cone shape.) I marked the overlap and cut a pie wedge from the circle. When I was satisfied, I transferred my paper pattern to sheet steel and cut the pieces Pull the edges of the wedge opening together and tack weld together. Grind welds so the surface is smooth.

Tack weld the conical piece onto the cylindrical piece that saddles the roof. Trim and grind the edges smooth.

The smokestack was a short piece of 1/2 inch mild steel tubing. I welded a flat piece of steel across the inside of the tubing and drilled a hole in it so I could clamp the boiler and smokestack assembly to the roof with a long screw. That meant drilling a hole in the roof and in the cone on the faux boiler. (The sheet steel is thin and I kept welding to a minimum to avoid burning holes in the sheet steel.)

I drilled very small holes in the washers at the sides of the windlass drums. This was to receive 50 pound test monofilament fishing line tied off with a knot. I also made similar holes in the claw that closes the back of the bucket and in the top front of the bucket. On the boom I simply rigged the lines in "U" pattern. (The line runs from one side of the windlass, passes through the boom and out the other side, and runs back to the windlass on the other side.) The lines are visible in the photo from the previous step and the photo from the Introduction. The line that releases the back of the bucket for dumping is simply tied to the front of the engine house. (If the knots in the ends of the fishing line want to unravel, cover them with a dab of hot glue.)

I cleaned up spatter and flux dust from the welds. I ground edges to remove anything sharp that could cut. I painted the steam shovel. I chose green because I learned that is our grandson's favorite color. A little black makes a nice accent.

Our grandson likes his steam shovel. He has not yet learned how to use the cranks to raise and lower the boom and the bucket, but he recognizes how it goes together with his Mack truck from last year's birthday. (A link to Instructables on making the Mack AC truck can be found in the Introduction.)