An Enlightening Tutorial On Making a Crane Vehicle Toy
Every construction site needs a crane to move materials. Here’s a simple-to-build crane that looks more complicated to make and operate than it actually is. When it’s completed, this toy has a cab that rotates 360", a boom that raises and lowers, and a hook that goes up and down on a cable. The boom and crank handles lock into place to add even more realism.
NOTE: You can build the “tracked look” wheel arrangement in the images here, or you can use the chassis instructions from the bulldozer project. You can adapt this design to some of the other four wheeler or vehicle-based toys shown on this site.
For instance, instead of making a chassis assembly for this crane, design your own flatbed car for the Santa Fe train. Or make one of the trucks longer and mount the crane on the bed.
Before you begin make sure you have the S-hook, washers, screw eyes, and string on hand.
For instance, instead of making a chassis assembly for this crane, design your own flatbed car for the Santa Fe train. Or make one of the trucks longer and mount the crane on the bed.
Before you begin make sure you have the S-hook, washers, screw eyes, and string on hand.
THE TUTORIAL
1. CHASSIS
Start by gluing up stock for the chassis. Use three pieces of 3/4" stock to get a 2-1/4"-thick block. Once the glue dries, square up the block using a belt or disc sander. Don't attempt to join or plane the stock square with a power jointer or planer because this stock is too small to handle safely.
After the block has been squared, locate and drill the 5/16"-diameter axle holes. Next, drill the pivot pin lock hole using a 1-1/4"-diameter spade bit or Forstner bit. If you’re using the bulldozer chassis, the hole will be bigger than the width of the center beam; but that’s no problem because the pivot pin will still clear the tracks and wheels.
Once you've drilled all the holes, chamfer the ends of the chassis 30°, then sand I he chassis smooth—be careful to keep the top edges sharp and square. Set the chassis aside and go on to the next step.
2. WHEELS
Cut out the six main wheels. They are 1 -1/4" in diameter and can be made with a 1-3/8"-diameter hole saw. Next, cut out the four secondary wheels and the cab pivot pinlock using a 1 - 1/8"-diameter hole saw. The hole saw leaves a rough edge on the wheels, so sand them smooth once you’ve finished cutting them out.
When making the main wheels, also make the blanks for the boom, and hook crank wheels. These blanks are 1-1/2" in diameter and are made with a 1-5/8"-diameter hole saw. Make two of the blanks out of 3/4" stock and resaw them to a 3/8" thickness, or just make four wheels out of 3/8" stock. Set the crank wheels aside for further machining later.
3. CAB
To make the cab, first transfer the pattern for the sides to a piece of 3/4"-thick stock. Carefully locate all angles and holes, except the crank lock holes; these will be located and drilled later. Next, drill all the holes; then, using a bandsaw or scroll saw, cut out the contours on the sides. Then, with a bandsaw or scroll saw, resaw the sides to a 3/8" thickness.
An alternative to cutting out and resawing stock for the sides is to make the sides out of 3/8" stock. When doing this, cut out the parts first; then stick them together with carpet tape and drill the holes—this will keep the holes in alignment.
After you've finished with the drilling and cutting operations on the sides, drill a 3/8"-diameter x 1/2"-deep hole in the top of the cab roof for the exhaust slack. Next, drill a 3/8"-diameter x 1/2"' deep cab pivot pin hole where indicated in the cab floor (see image below.)
Start by gluing up stock for the chassis. Use three pieces of 3/4" stock to get a 2-1/4"-thick block. Once the glue dries, square up the block using a belt or disc sander. Don't attempt to join or plane the stock square with a power jointer or planer because this stock is too small to handle safely.
After the block has been squared, locate and drill the 5/16"-diameter axle holes. Next, drill the pivot pin lock hole using a 1-1/4"-diameter spade bit or Forstner bit. If you’re using the bulldozer chassis, the hole will be bigger than the width of the center beam; but that’s no problem because the pivot pin will still clear the tracks and wheels.
Once you've drilled all the holes, chamfer the ends of the chassis 30°, then sand I he chassis smooth—be careful to keep the top edges sharp and square. Set the chassis aside and go on to the next step.
2. WHEELS
Cut out the six main wheels. They are 1 -1/4" in diameter and can be made with a 1-3/8"-diameter hole saw. Next, cut out the four secondary wheels and the cab pivot pinlock using a 1 - 1/8"-diameter hole saw. The hole saw leaves a rough edge on the wheels, so sand them smooth once you’ve finished cutting them out.
When making the main wheels, also make the blanks for the boom, and hook crank wheels. These blanks are 1-1/2" in diameter and are made with a 1-5/8"-diameter hole saw. Make two of the blanks out of 3/4" stock and resaw them to a 3/8" thickness, or just make four wheels out of 3/8" stock. Set the crank wheels aside for further machining later.
3. CAB
To make the cab, first transfer the pattern for the sides to a piece of 3/4"-thick stock. Carefully locate all angles and holes, except the crank lock holes; these will be located and drilled later. Next, drill all the holes; then, using a bandsaw or scroll saw, cut out the contours on the sides. Then, with a bandsaw or scroll saw, resaw the sides to a 3/8" thickness.
An alternative to cutting out and resawing stock for the sides is to make the sides out of 3/8" stock. When doing this, cut out the parts first; then stick them together with carpet tape and drill the holes—this will keep the holes in alignment.
After you've finished with the drilling and cutting operations on the sides, drill a 3/8"-diameter x 1/2"-deep hole in the top of the cab roof for the exhaust slack. Next, drill a 3/8"-diameter x 1/2"' deep cab pivot pin hole where indicated in the cab floor (see image below.)
Next, locate and install two screw eyes in the cab rear panel where indicated in the drawing above. Since these hooks are located close to the top of the panel, you'll need to make starter holes to prevent the stock from splitting.
You're now ready to assemble the cab. Start the assembly by gluing and clamping the sides to the floor and rear panel. After the glue dries, sand the back of the assembly flush. Next, round the counterweight and glue and clamp this into place. While the glue is drying, round the roof and install the screw eye in it as indicated in the instructions. Set the roof aside for assembly later.
The final step in constructing the cab is to glue and clamp the boom anchor supports in place. After the glue dries, drill the 3/8" boom anchor pin holes using the holes already drilled in the sides as guides.
4. CRANK ASSEMBLIES
Take the crank wheels you've already made and, if they’re 3/4" stock, resaw them into equal parts. Sand the wheels, then redrill the 1/4"-diameter holes to a 3/8" diameter (the larger hole is necessary for the 3/8"- diameter axles.) To properly center the drilling operation, use a twist drill bit. Next, drill the 1/4" handle holes in two of the wheels; then, set all of the wheels aside.
For the locking crank system to work, the axles must slide back and forth. Since they slide, the holes for the boom and hook cables are not placed in the centers of the axles. Place the holes according to the photo below; then drill them using a V-block, or tilt the table.
You're now ready to assemble the cab. Start the assembly by gluing and clamping the sides to the floor and rear panel. After the glue dries, sand the back of the assembly flush. Next, round the counterweight and glue and clamp this into place. While the glue is drying, round the roof and install the screw eye in it as indicated in the instructions. Set the roof aside for assembly later.
The final step in constructing the cab is to glue and clamp the boom anchor supports in place. After the glue dries, drill the 3/8" boom anchor pin holes using the holes already drilled in the sides as guides.
4. CRANK ASSEMBLIES
Take the crank wheels you've already made and, if they’re 3/4" stock, resaw them into equal parts. Sand the wheels, then redrill the 1/4"-diameter holes to a 3/8" diameter (the larger hole is necessary for the 3/8"- diameter axles.) To properly center the drilling operation, use a twist drill bit. Next, drill the 1/4" handle holes in two of the wheels; then, set all of the wheels aside.
For the locking crank system to work, the axles must slide back and forth. Since they slide, the holes for the boom and hook cables are not placed in the centers of the axles. Place the holes according to the photo below; then drill them using a V-block, or tilt the table.
Dry-assemble the crank wheels to the axles and locate the crank locking holes on the cab sides. Put the holes on the right side for a right-handed child and on the left for a lefthander. Remove the crank assemblies and drill the holes in the cab sides.
Assemble the crank assemblies with glue. The boom axle goes in the bottom rear position and the hook axle goes in the top front position.
5. CRANE BOOM
After cutting the crane boom stock to length, locate all the holes and contours. Next, drill the 3/4" -diameter "lightening” holes, the 7/16"-diameter anchor pin hole, and the 1 /8"-diameter cable run holes located in the front of the boom and in the cable guides.
Round the boom contours on a disc or belt sander. After finishing all the contouring of the boom, glue and clamp the cable guides into place.
Sand the boom and slide it into position between the boom anchor supports located on the cab. Check the fit. If it’s too tight, sand the boom. After achieving a good fit, secure the boom in place by gluing the anchor pin into position.
Glue the cab pivot pin into the bottom of the cab floor. Then, drill a 7/16"-diameter hole in the center of the platform. Next, using a 3/8" twist drill, enlarge the 1/4"-diameter hole of the cab pivot pinlock to 3/8" diameter. Glue the lock to the pin.
Place the cab assembly on the platform with the pivot pin through the hole in the platform. Glue the cab pivot pinlock assembly through the cab floor and into the cab floor. The platform is still loose at this point but attached to the cab assembly by the pivot pinlock.
After the glue has dried, carefully spread more glue on the top of the chassis. Be careful not to get any in the lock-hole. Attach the platform to the chassis and clamp in position. Finally, assemble the wheels and axles to the chassis with glue.
7. HOOK AND BOOM
ASSEMBLY
Begin stringing the crane boom by cutting a 30" length of nylon cord. Slightly singe both ends of the cord with a match to prevent it from becoming unraveled. Next, thread one end of the line through one of the holes in the back crank axles.
Bring up the line through the screw eye above it in the rear panel, then take it straight out the front and through the 1/8” hole in the side of the boom. After you thread the line through the boom, lead it back down to the cab, through the other screw eye in the rear panel, and through the other hole in the back axle.
Hold the boom level and pinch the cord where it comes out of the axle. Now raise the boom and tie a knot where you’re pinching it. Trim the cord and singe the knot with a match.
For the hook assembly, cut a length of string about 3' long and slightly singe both ends to prevent unraveling. Tie one end around two or three 1/2" flat washers. Thread the other end through the hole in the end of the boom and down through the two cable guides.
Set the roof on the cab and run the cord through the screw eye on the roof and down through the front crank axle. Tie a knot in the end of the cord and singe the knot. If everything works satisfactorily, glue and clamp the roof in place.
Finally, take an S-hook and crimp one end of it around the washers. The S- hook will pick up a lot of items, so experiment with it. Attach a magnetic message hook for the refrigerator to the hook cable, or even a little toy bucket. Whatever you and your young construction helper decide, you'll surely agree that this toy is a great deal of fun.
Assemble the crank assemblies with glue. The boom axle goes in the bottom rear position and the hook axle goes in the top front position.
5. CRANE BOOM
After cutting the crane boom stock to length, locate all the holes and contours. Next, drill the 3/4" -diameter "lightening” holes, the 7/16"-diameter anchor pin hole, and the 1 /8"-diameter cable run holes located in the front of the boom and in the cable guides.
Round the boom contours on a disc or belt sander. After finishing all the contouring of the boom, glue and clamp the cable guides into place.
Sand the boom and slide it into position between the boom anchor supports located on the cab. Check the fit. If it’s too tight, sand the boom. After achieving a good fit, secure the boom in place by gluing the anchor pin into position.
Glue the cab pivot pin into the bottom of the cab floor. Then, drill a 7/16"-diameter hole in the center of the platform. Next, using a 3/8" twist drill, enlarge the 1/4"-diameter hole of the cab pivot pinlock to 3/8" diameter. Glue the lock to the pin.
Place the cab assembly on the platform with the pivot pin through the hole in the platform. Glue the cab pivot pinlock assembly through the cab floor and into the cab floor. The platform is still loose at this point but attached to the cab assembly by the pivot pinlock.
After the glue has dried, carefully spread more glue on the top of the chassis. Be careful not to get any in the lock-hole. Attach the platform to the chassis and clamp in position. Finally, assemble the wheels and axles to the chassis with glue.
7. HOOK AND BOOM
ASSEMBLY
Begin stringing the crane boom by cutting a 30" length of nylon cord. Slightly singe both ends of the cord with a match to prevent it from becoming unraveled. Next, thread one end of the line through one of the holes in the back crank axles.
Bring up the line through the screw eye above it in the rear panel, then take it straight out the front and through the 1/8” hole in the side of the boom. After you thread the line through the boom, lead it back down to the cab, through the other screw eye in the rear panel, and through the other hole in the back axle.
Hold the boom level and pinch the cord where it comes out of the axle. Now raise the boom and tie a knot where you’re pinching it. Trim the cord and singe the knot with a match.
For the hook assembly, cut a length of string about 3' long and slightly singe both ends to prevent unraveling. Tie one end around two or three 1/2" flat washers. Thread the other end through the hole in the end of the boom and down through the two cable guides.
Set the roof on the cab and run the cord through the screw eye on the roof and down through the front crank axle. Tie a knot in the end of the cord and singe the knot. If everything works satisfactorily, glue and clamp the roof in place.
Finally, take an S-hook and crimp one end of it around the washers. The S- hook will pick up a lot of items, so experiment with it. Attach a magnetic message hook for the refrigerator to the hook cable, or even a little toy bucket. Whatever you and your young construction helper decide, you'll surely agree that this toy is a great deal of fun.