Christmas Rotary

This rotary is a simple machine using several gears to spread cheer this holiday season.

- 3D printer

- A good attitude

The first step in our process was figuring out the sizing and ratios of gears to fit them all together on the top. Fusion has a feature which allows you to create gears by choosing the number of teeth, pitch, and angles. This tool was incredibly useful in creating the gear with the correct ratio to work together well. The outer ring was made by creating a large gear and holing a cylinder with that gear.

The base took several steps to complete to perfection. The original body was just a hollow cylinder in which the other pieces would fit. In designing this, it came to my attention that this process would take too much time and use too much material, so I decided to hole out most of the circumference of the cylinder and just leave four pillars to support. Even with this design, it would take too much time to print, so I split the body into two pieces and printed them separately so it would take half the time.

The bottom plate is just a flat disk with an indent to fit the body around. It also has support to hold the bar that will eventually spin the bevel gear ot spin the top. This piece was straight-forward to design and to print because the general shape was quite simple, but this piece is vital to keeping the inner structure supported.

These bevel gears were also made simply with a different feature on Fusion called McMaster-Carr which is typically used to import real-life mechanical pieces to model projects to be done physically, but it also gave a great resource to quickly and easily make complicated gears. The crank was made by arranging several long, thin cylinders and filleting the ends.

First using the “create” feature, I created a sphere thats about 1 in diameter and a smaller sphere thats about .75 inches in diameter. Then select the smaller sphere and place it on top of the larger one. Be sure that it is centered.

Using the same feature create a cylinder that is .75 inches in diameter and roughly .1 inches in height (adjust as desired).Make another cylinder that is .4 inches in diameter and .4 inches height.Place the taller cylinder on top of the thinner one.Right click, hold, and drag over the two cylinders and Under “Modify” and use the combine feature to combine them and make a hat .Then drag the hat and place it on top of the snowman body (the two spheres).

Then create a box 0.6 inches in length.Next, using the create feature, make a torus that is .1 inches in diameter.Then right click it and create a copy.Drag the torus’s so that they are next to each other and touching in the center.As you did in step 6, combine the torus’s to make a bow.Place the bow on top of the box, be sure to center it.

To make the tree, on the vertical face create a sketch of a triangle that is .7 in height, .5 in on the bottom leg, and a hypotenuse of .86 inches.Then under create, use the revolve feature to turn the triangle into a cone.Copy the first cone and paste it twiceResize the first cone to 1.5 inches in height and the second one to 1.1 inches in height.Stack the three cones from largest to smallest.

Finally, to make the pegs, create a cylinder that is 1 inch in diameter and .4 inches in height .Make 2 additional pegs and be sure to have 1 on each figurine (the snowman, gift box, and tree).Use the combine feature on each figurine so that all parts are aligned.Then make 2 additional copies of the gift box figurine and the tree figurine.