Halloween Themed Whirligig

About a year ago I made a whirligig, some of you might have seen. If you haven't it's here.This year I wanted to make one more, this time a Halloween themed whirligig. Was a really fun process and I believe I have learnt lots from it.

But for those who do not know what a whirligig is, here is its definition taken from wiki.

Wind-driven whirligigs

A wind-driven whirligig transfers the energy of the wind into either a simple release of kinetic energy through rotation or a more complicated transfer of rotational energy to power a simple or complicated mechanism that produces repetitive motions and/or creates sounds. The wind simply pushes on the whirligig turning one part of it and it then uses inertia. The simplest and most common example of a wind-driven whirligig is the pinwheel. The pinwheel demonstrates the most important aspect of a whirligig, blade surface. Pinwheels have a large cupped surface area which allows the pinwheel to reach its terminal speed fairly quickly at low wind speed. Increasing the blade area of the whirligig increases the surface area so more air particles collide with the whirligig. This causes the drag force to reach its maximum value and the whirligig to reach its terminal speed in less time. Conversely the terminal speed is smaller when thin or short blades with a smaller surface area are utilized, resulting in the need for a higher wind speed to start and operate the whirligig. Whirligigs come in a range of sizes and configurations, bounded only by human ingenuity.

Source: Wiki

Here is also a video showing the whole process, make sure you watch it.

And here you can see it in action!

Step 1: Propeller Hub

Tools and Materials required:

• 8 cm diameter hole saw
• Hand saw
• Sandpaper (80 and 100 grit)
• Hand miter saw (I would not recommend an electrical miter saw, it is not safe for such a small working piece)
• Drill press
• Small clamp
• A piece of wood 4 cm thick and wide enough to cut a 8 cm disc out of it.
• Pencil
• Safety glasses

First cut a wooden disc on the drill press using a 8 cm diameter hole saw. This will give you a perfectly cut disc and also a perfectly centered center hole. Divide your disc into 4 equal parts (*) and mark with a pencil the four positions for the cuts.

Now set your miter saw at 45 degrees angle and start cutting 4 mm wide slots for the propeller fins. The slots must be about 1 cm deep. It is a good idea to fasten the disc on the miter saw using a clamp, because it holds the wood so I does not slip and it is also safer for you.Your mitre saws blade must be thinner that 4 mm so two cuts required for each fin slot. Remove the excess material from each slot using a hand saw slightly angled. Use some sandpaper to smooth any rough edges. At the end of this step you should have something like this.

* There is a great tutorial online showing you how to divide a circle into 4 equal parts. Please check it out here.

Step 2: Fins

Tools and Materials required:

• 4 mm plywood (I have used Baltic birch plywood)
• Band saw (If you don't have a band saw you can use a hand saw or scroll saw or jig saw)
• Wood glue
• Sandpaper (100 grit)
• Pencil
• Safety glasses

Use the template I provide to cut four fins out of the plywood, you can use any cutting tool you have like a scroll saw or jig saw or band saw or even a hand saw can do the job. Once you have finished cutting the fins give them a light sanding and with some wood glue place them in the slots on the hub. Let the glue dry for a couple of hours.

Step 3: Cutting the Disks for the Gears

Tools and Materials required:

• Drill press
• Clamp
• 3.5 cm diameter hole saw
• 10 cm diameter hole saw
• 2 cm thick plywood (Again here I have used Baltic birch plywood)

Use your 3.5 cm hole saw to cut three discs out of the plywood and also three more with your 10 cm diameter hole saw. You are going to need those discs to make the gears for the whilrigig

Step 4: Making the Gears

Tools and Materials required:

• The wooden discs you have just cut
• 2 car timing belts 2 cm wide
• Staple gun
• Scissors
• Safety glasses

So instead of making 100% wooden gears which is difficult, time consuming and sometimes inaccurate, a better approach is to make gears using timing belts. The teeth of a timing belt are accurately spaced so you do not have to worry about making them wrong.

Now take each one of your plywood discs and roughly measure how many centimeters of timing belt you need. Cut the timing belt with a pair of scissors and secure the one end of the belt on the disc with a staple gun (You can also use super glue if you want or contact cement or even small nails). Wrap the timing belt around the plywood disc and check where the two ends come together. You want to have the same distance between the teeth as the rest of the teeth around the belt. If you see that this distance is not the same you can adjust your plywood disc with a sander to make it slightly smaller. Repeat if needed until you have a nice gear.

Repeat the process for all your plywood discs until you have six gears that work nicely with each other.

Step 5: Compound Gear Train

Tools and Materials required:

• Drill
• Drill bit with countersink
• 4 x (3.5 x 30 mm wood screws)
• Wood glue
• Threaded rod
• Safety glasses

Gear Generator is a very powerful online tool that allows you to design gears and also test how they work. It also gives you useful information about gear ratios and other stuff. Click on the link to see the gear configuration I have used for this whirligig.

So now you have to make two gear pairs as shown on picture 2.

Simply use a threaded rod to align the center holes of a big gear and a small gear. Apply some glue on the small gear and attach it on the bigger gear. Use your drill with a drill bit to make two pilot holes on the small gear and screw them together as shown on the picture 3.

Repeat the process for the second compound gear.

Step 6: Ball Bearings

Tools and Materials required:

• Miter saw or jig saw or band saw or radial saw.
• 22 mm spade bit (because we are going to use 22 mm diameter ball bearings)
• Drill
• Clamp
• 12 mm thick plywood
• Pencil
• Safety glasses

For now you will need to cut a 30 x 15 cm piece of 12 mm thick plywood. You will need it to mount the gears you have just made on it. Once you have it cut, take the small driver gear and mark its center hole position on the plywood (picture 3). Arrange the compound driven gear so it is attached to the small driver gear and do the same. (Picture 4). Repeat for the second compound driven gear (Picture 5). I wanted to include a PDF for the drilling positions but if you choose a different timing belt from mine (thicker or thinner) then my PDF would be useless. So for now this is the only way to mark your drilling positions.

Now with your 22 mm spade bit drill a hole on each mark you have made, all the way through the plywood. It is a good idea to use a clamp to secure your work piece on your bench while drilling for safer and more comfortable work. Also use a sacrificial piece under your work piece if you do not want to damage your work bench.

Step 7: Gluing the Bearings

Tools and Materials required:

• Epoxy glue
• 3 x (22 mm diameter ball bearings)

Mix the two components of the epoxy on a scrap piece of wood and apply some glue into the holes on the plywood. Then place the ball bearings into the holes and let the glue set for about 30 mins before you proceed to the next step.

Step 8: Mounting Propeller and Driver Gear

Tools and Materials required:

• Threaded rod
• Wing nuts, nuts and washers
• Angle grinder or hack saw
• Safety glasses
• Gloves

Here is where the tricky part begins!!

Before you proceed any further I would suggest you watch the embedded video to understand exactly how the gears should go. So, using your angle grinder or your hack saw cut a 14 cm long piece off your threaded rod.This will be the axle for your driver gear and propeller. Use two nuts and two washers to fasten the axle on the ball bearing. Make sure the axle is in such position that you can fit the propeller on the one side and the small driver gear on the other side.

The last five images will give you an idea for the distances required and the components needed.

Step 9: Mounting First Compound Gear

Tools and Materials required:

• Threaded rod
• Wing nuts, nuts and washers
• Angle grinder or hack saw
• Safety glasses
• Gloves

Now lets mount the second gear. First cut a 12 cm long piece out of threaded rod, use two nuts and two washers to secure the threaded rod on the bearing making sure that on the outside (the side where the propeller is) the threaded rod edge is flush to the nut. Now fasten the compound driven gear using a washer and a wing nut.

At the end you should have something like this.

Step 10: Mounting Second Compound Gear

Tools and Materials required:

• Threaded rod
• Wing nuts, nuts and washers
• Angle grinder or hack saw
• Safety glasses
• Gloves

Again cut a 12 cm long piece out of your threaded rod and repeat as the previous step. But there is only one difference. This gear has to be around 3 cm away from the plywood so we need a spacer for that. You can either use a piece of metal tubing as a spacer or like I did use one more nut on the threaded rod. Please check the last four images to see how this gear looks like.

Step 11: Repairing Last Driven Gear

Tools and Materials required:

• Drill
• 22 mm spade bit
• Epoxy glue
• 1 x (22 mm dia ball bearing)
• Safety glasses
• Scrap piece of wood or plywood

This gear should be already made since step 3 and 4. Now we need to mount a ball bearing on it but the gears center hole will make it difficult for the spade bit to be properly centered. All you need to do is to make a guide for the spade bit. This can be done with a scrap piece of wood or plywood and your spade bit.

Drill a 22 mm hole on your scrap piece and align this hole to the center hole of your gear. Now drill through the guide and all the way through the center of your gear.

Use some epoxy glue to secure your ball bearing into the hole on the gear you have just made.

Step 12: Mounting Last Driven Gear

Tools and Materials required:

• Few nuts, wing nuts and washers

Remove the wing nut that holds the first compound gear and replace it with an ordinary nut. Now add another nut just 3 cm above it and pass the gear through the threaded rod. Now use a washer and a wing nut to secure the gear on the threaded rod.

The whole compound gear train should look like this

Step 13: Assembling the Gear Box

Tools and Materials required:

• Table saw or jig saw or scroll saw or band saw or radial arm saw
• Drill
• Drill bit with countersink
• Few 3.5 x 30 mm wood screws
• Router
• Round router bit
• 12 mm thick Plywood
• Safety glasses
• Gloves

Cut four pieces out of your plywood, the two of them must be 15 x 15 cm (for the two sides), one must be 32.4 x 15 cm (for the bottom) and the last one 34.4 x 17 cm (for the top). Drill some pilot holes for the screws and assemble the box. Finally with your router and a round router bit, round over all the edges of your top piece.

Step 14: Making the Guillotine

Tools and Materials required:

• Band saw or table saw or scroll saw or jig saw
• Radial arm saw or router with 1/4 in router bit (For making the grooves)
• Hand miter saw or just a hand saw
• Wood glue
• Brad nail gun or just some nails
• Scrap pieces of wood
• A 8 x 5 cm piece of 4 mm plywood
• 12 mm plywood
• Safety glasses

In this step you will need to make two shallow grooves on the two side parts of the guillotine for the "blade". If you use a table saw or a router is a good idea to do that now as your work piece is still long and you have space to hold it as you work. So make two 6 x 6 mm grooves on a piece of wood using your router table or your table saw and then rip it to the appropriate size (1.6 x 1.6 cm) until you have something like this. Cut two pieces of 1.6 x 1.6 wooden dowel 6 cm long and glue them on the pieces with the groove as shown on picture 10. Use your brad nail gun to secure the two pieces together and keep your fingers away from where you nail. It is a good idea to wear protective gloves and of course safety glasses. Now connect the two sides of the guillotine using a 6.5 cm piece of the same 1.6 x 1.6 wooden dowel as shown here. To reinforce your guillotine you can use a piece of 12 mm thick plywood and glue it as shown here. Cut out a 8 x 5 cm out of 4 mm thick plywood and slide it through the grooves. This will be the blade of the guillotine. To make it look a bit better I have cut two strips of wood 3 mm thick and 1.6 cm wide and glued it on the upper section of the blade as shown here. Finally cut out a 13.5 cm long piece out of your dowel and glue it on the top of the guillotine as shown on the picture 19. Again use some brads to secure all the work pieces together.

Step 15: Mounting the Guillotine on the Gear Box

Tools and Materials required:

• Drill
• 6 mm drill bit
• Brad nail gun or some 25 mm long nails
• Wood glue
• Safety glasses

This is easy! Just use some wood glue and some brads to secure the guillotine on the top of the gear box. Make sure that you place it just above the last gear (the one that turns slower). There are two holes for the wires that should be drilled but you can do this later on.

Step 16: Making the Hero! (Pour Guy)

Tools and Materials required:

• Saw
• Orbital sander
• Hand miter saw
• Wood glue
• Brad nail gun
• Safety glasses

For the body: Start by cutting a piece of wood 6 x 4 x 3 cm. The rest is just free hand shaping. You can use whatever you want to shape the body. I have used some chisels to roughly shape it and then my orbital sander to make it smooth.

For arms and legs: Take a wooden dowel and cut it in small pieces. Shape them using some sand paper or a chisel but be careful because those parts are quite small.Use some glue and brads to make him look like he is on his knees.There is no recipe here. Just work free hand.

Step 17: Back to the Last Driven Gear

Tools and Materials required:

• Drill
• 8 mm drill bit
• 8 mm thick wooden dowel
• Wood glue
• Safety glasses

Take your last driven gear and make a hole to it 2.5 cm from the gears edge. Add some wood glue and place a 4 cm long wooden dowel in the hole. Place the gear back to its place.

Step 18: Mechanism That Lifts the Blade

Tools and Materials required:

• Drill
• Drill bit with countersink
• Saw or band saw
• Wood glue
• Some scrap pieces of wood
• Safety glasses

We need to make a mechanism that lifts the blade. Take a 6 x 3 x 2.5 cm piece of wood and screw it inside the gear box 4 cm from the boxes edge. Then take the attached template and cut the shape of the arm. Use a 3 mm drill bit to make a hole on the arm on both sides. One for the pivot point and one for where the wire goes.

Step 19: A Piece of Wire

Tools and Materials required:

• A piece of wire
• Pliers
• small wood screws (16 mm)
• Screwdriver

This wire is used to lift the guillotine blade and also pull it back down. Take your piece of wire and make an aye pin on the one end using your pliers. Then place the eye pin inside the notch of the lifting arm and add a screw. The screw works as a pivot point so you want your piece of wire to move freely inside the notch and around the screw.

Step 20: Attaching the Steel Wire

Tools and Materials required:

• Scrap pieces of wood
• Wood glue
• Brad nail gun
• Steel wire
• Safety glasses

Because of the fact that the screw that holds the arm on the gear box must not be very tightened this might cause a problem because it lets the arm also move sideways. We don't want that because in some cases the dowel on the gear might not grab the lifting arm and causes problems. To avoid that we need something to keep the lifting arm from moving out, and thats just a vertical piece of wood 1 mm away from the lifting arm. You can see how it works on the picture 2. Finally make a small hole on the upper side of the blade and feed the wire through it. Now if everything is as it should be when you rotate the driver gear the dowel should lift the arm to a point and then as it rotates disengages and the arm and blade fall back down. You can also see the motion on the embedded video.

Step 21: The Podium

Tools and Materials required:

• 11 x 6.5 x 4 cm piece of wood
• Saw or band saw
• Wood glue
• Brad nail gun or nails
• Safety glasses

You need to make a kind of stairs or podium where our hero is on so his neck is close to the blade. Take an 11 x 6.5 x 4 cm piece of wood and shape it to look like stairs. Place it in front of the guillotine and use some glue and nails to secure it.

Step 22: Back to the Hero!

Tools and Materials required:

• Wooden dowels
• Wood glue
• Brad nail gun
• Drill
• 3 mm drill bit
• Epoxy glue
• Steel wire
• Pliers
• Sander or sand paper
• Safety glasses

Lets add the final touches to our hero. We need to make his arms and head. Again here take some wooden dowels and work free hand to make the arms. Use some wood glue and some nails or a brad nail gun to secure the arms on the body. For the head use a sander or some sandpaper to roughly shape a piece of wood to look like head. You don't have to be extra accurate when making the hero. It should be just a figure.

With a drill and a 3 mm drill bit, drill a hole all the way through the head, around 1 cm from the bottom of the head. Feed your steel wire through the hole and bend it U shape. Finally Drill two small holes on the guillotine as shown here fill them with epoxy and place the two ends of the wire in them. Let it dry and paint the whole thing! Its all done!

Step 23: About the People Who Helped Me Make My Project Come True!

A few days ago the people from GearBest approached me and kindly asked me if I wanted to do an honest review on the tools they have on their web site. Of course I accepted and they send me a Bosch cordless drill to test it out.I have to say that this was the only drill I have used while making this whirligig. It is very strong for its size and with 28 Nm of torque I was able to do all the tasks required for this build easily. The two speeds help a lot for drilling and driving screws and also the 1500 mAh Li ion battery lasts a long time.

So 9/10 for this product. If you are interested in purchasing a drill like this please check here and use the word BOSCH for the coupon. Have fun!