Introduction: Build a Spork for Outer Space

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The following information is a single lesson in a larger Tinkercad project. Check out this and more projects on Tinkercad.

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Lesson Overview:

Now we're going to make a spork!

Step 1: Background

Who decided a fork was a good idea?

I mean, don't get me wrong, I use one everyday, and you probably do, too.

But not everyone does, and forks have only been in common use through out Europe and the Americas for about 200 years! And forks from thousands of years ago look nothing like the tools of today.

Then we have a relatively new invention, the Spork! Half spoon, half fork! Whoa!

A small change, an appreciable difference.

What change comes next? What would we be designing, today, if the fork wasn't in wide use? Are we missing the next best thing?

Only one way to find out, design a better utensil!

Instructions

  1. Continue to the next step.

Step 2: Creating the Basic Shape

Let's think about the basic function of a spoon. A spoon is a mouth-sized bowl for moving a small volume liquid food.

So we need to make a mouth sized bowl. That tells me we want a round shape that is no larger than about 40mm wide (I cheated, I measured an existing spoon, please don't tell anyone!)

Let's make that shape, now.

Instructions

  1. Drag out a sphere to the workplane and make it 100mm long, 40mm wide, and 20mm tall.
  2. Continue to the next step.

Step 3: Making the Top Flat

Now, a bowl isn't a full sphere, it's a hemi-sphere (half a sphere).

The top part of our spork needs to be flat, so we need to remove the top of our squished oval so that we have a flat surface.

Why didn't we start with a hemi-sphere? Because, by trimming a sphere, we can choose where we want the bowl to begin or end. We might need this adjustability when we test our spork!

Instructions

  1. Drag out a box to the workplane and make it 110mm long, 40mm wide, and 20mm tall.
  2. Use the Z Axis translation arrow to pull the box 10mm off of the workplane.
  3. Turn the box in to a hole and then use the Align tool to center the box over the oval along the X and Y axis
  4. Select both of the objects and group them.
  5. Continue to the next step.

Step 4: Hollowing Out the Bowl.

Now, we need to make a hollow for our food.

We may think of a spoon as a thin piece of metal in a bowl shape, but when we're designing one, we need to build it out of positive and negative spaces.

So the bowl is a spherical hollow that intersects with a solid hemi-sphere. I

t's a novel thing to think of the world in this way, which is why we're taking the care to share this with you.

Instructions

  1. Copy and paste our object to the side of the original so we can work on it.
  2. Drag out a box to the Workplane and make it 50mm long, 50mm wide, and 20mm tall.
  3. Align the box so that it is centered on our copied shape on the Y and Z axes but so it shares the lower limit on the X axis.
  4. Turn the box into a hole and group it with our copied shape.
  5. Select this new shape and drag its Z translation handle up 5mm.
  6. Use the Align tool to center this new shape to our original hemi-sphere along the Y and Z axes, and align them to the upper limit along the X axis,
  7. Turn the bowl shape into a hole and group it with the hemi-sphere.
  8. Continue to the next step

Step 5: Shaping the Fork

Good job making the spoon! We're taking design of this tool one step at a time. Isn't it fun watching it take shape?

Now it's time to shape the fork. What are some characteristics of a fork?

Well, a fork is a set of sharp, narrow tines, generally uniform in length.

An oval, however, is not conducive to making tines of uniform length. Let's fix that.

Instructions

  1. Drag a wedge shape to the workplane.
  2. Rotate the wedge around it's Z axis 90° (clock wise) so that it points in the positive direction along the X Axis.
  3. Make the wedge 34mm long (along the X axis), 30mm wide (Y axis), and 20mm tall (Z axis).
  4. Move the wedge so that it fits within the hint.
  5. This shape and its position are arbitrary, meaning there are plenty of opportunities to tune these values.
  6. Turn this wedge into a hole and group it with your spoon.
  7. Continue to the next step.

Step 6: Cutting the Tines

Now we have a spoon on one side and the uniform length of a fork on the other. Ready to cut the tines?

Like we used a negative space to define the bowl of the spoon, we're going to use negative spaces to define the shape of the tines.

Instructions

  1. Drag out a green roof to the workplane.
  2. Rotate the roof 90° about its Z axis, and then again 90° about its Y axis so that it points in the positive direction along the X axis.
  3. Resize the roof so that it is 40mm long (along the X axis) and 3mm wide (along the Y axis).
  4. Align the roof to the center of the Spork along the Y axis and the bottom limit of the Z axis. The alignment along the X axis is, again, arbitrary. Adjust the length and position of these roofs as an experiment!
  5. Duplicate the green roof twice and move the Duplicates 7mm along the Y Axis, one in the the positive direction and one in the negative direction.
  6. Select your three roof objects, turn them into a group and turn this group into a hole.
  7. Now group the tines with the rest of the spork, and we're done!
  8. Continue to the next step.

Step 7: Printing Your Spork

Now here's where designs become a challenge. Not all designs are easy to manufacture. 3D printing can produce things other tools can, but there are still limits.

For example, 3D printers can't print on top of empty space. These features, called overhangs, will cause the 3D printer to dispense material into thin air.

To accomplish prints with overhangs, 3D printers use "support scaffolding" or printed temporary supports to hold up the part. This material can be removed but may require some "Finishing Work" such as sanding.

It's best to minimize this finishing work.

To minimize this work, we'll rotate our final design around its Y axis.

The least amount of finishing work will be required if we rotate it 90° so that its tines are pointing down.

However, rotating it 180° about the Y axis may be a more stable way to print.

Experiment with both!

Instructions

  1. Drag out a green roof to the workplane.
  2. Rotate the roof 90° about its Z axis, and then again 90° about its Y axis so that it points in the positive direction along the X axis.
  3. Resize the roof so that it is 40mm long (along the X axis) and 3mm wide (along the Y axis).
  4. Align the roof to the center of the Spork along the Y axis and the bottom limit of the Z axis. The alignment along the X axis is, again, arbitrary. Adjust the length and position of these roofs as an experiment!
  5. Duplicate the green roof twice and move the Duplicates 7mm along the Y Axis, one in the the positive direction and one in the negative direction.
  6. Select your three roof objects, turn them into a group and turn this group into a hole.
  7. Now group the tines with the rest of the spork, and we're done!

Congratulations, you have completed this project!

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