Make Your Own Cardboard Dolphin!

If you are looking to make a cardboard dolphin, this is the instructable for you! Above is the finished product of everything you can achieve through this instructable.

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Step 1: Materials/tools

Here are some materials/tools you will need as you make your cardboard dolphin:

  1. Cardboard
  2. Matte Knife
  3. Cutting Matte
  4. A Pencil
  5. A Ruler
  6. Paper

Step 2: Sketch a Dolphin

You will make multiple sketches of the dolphin. Each description below is a sketch you might want to create.

1. Start with a simple sketch of a dolphin in the position of jumping out of the water. You can then add details of how you will use cardboard circles (you will make these later) to give volume to your dolphin.

2. This sketch can be zoomed in on how you will connect the fins to the dolphin.

3. You can draw a sketch of the nose from the side so you can see how you might define it more.

Step 3: Draw Your Pieces on Your Cardboard

Draw your pieces on cardboard:

You will need three spines, three tails, and two fins, and many circles of multiple sizes.

For the spines, tails, and fins, I would suggest that you draw one on the cardboard, cut it out, and use it as trace for the others.

You will make three spines. One spine (the middle one) will be cut out with a fin. So you can use the other spines as a trace, but before you cut it out, draw a fin as well.

When drawing the circles, you will need to measure out the diameters for each one. I usually increased or decreased each circle’s diameter by a half and inch or a quarter of an inch. The way I figured out what size to make each circle, was I measured the width of the base of the spine and added about half an inch too it, so that there would be a bit of extra girth around it, giving the dolphin more overall volume. I then proceeded to add about half an inch or a quarter of an inch to each previous circle so they would get bigger as the spine increased in width. At the peak of the spine, or the place the spine is widest, I started to decrease the diameter of each circle by about half an inch.

Drawing a perfect circle is hard, so here is an example of how I created my symmetrical circles. For this example, let's say that I want a circle with the diameter of four inches.

1.Draw a line that is four inches wide

2. Find the center of that line (two inches) and mark it

3. Move your ruler perpendicular to that line

4. Place your ruler with the two inch mark at the center point you created on the previous line

5. Draw this line starting at zero to four

6. You then will repeat steps four and five two more times diagonally between the first two segments

7. Now you have eight points on what will be the outside of your circle

8. Connect the points

9. Now you have your four inch circle!

Step 4: Cut Out Your Pieces

When cutting cardboard, you have to be careful and go slowly to get the best cuts. Make a light cut over the piece of cardboard you are cutting so your knife has a groove to follow when you add more pressure to the knife. You will have to go over the cut multiple times to cut through all the layers in the cardboard.

Step 5: Cut Slots Into Your Pieces

You will need to cut three slots into each circle to attach them to the spines. You need to measure the width of the cardboard so you know how wide to make these slots. Place the slots a quarter inch to a half an inch away from each other. When making the slots for the tail, the slots will be at the base of the spine. Make sure these slots are level with each other so the tails slide into the spine slots well. The slots for the pectoral fins will be in the cardboard circles between the dorsal fin and the nose. These slots should be, at the very least, a quarter inch from the spine slots.

Step 6: Put Your Dolphin Together!

To start assembling your dolphin, line the spines up and slide the tails into the slots (make sure the spine with the dorsal fin is in the middle). Now add the cardboard circles to the spine, giving your dolphin volume. Once the circles are on the dolphin, the final step would be to put the pectoral fins into the slide slots you created earlier.

Step 7: You Have Crossed the Finish Line!

You now have your dolphin! You can choose to paint it or add other decorations to it. I hope you enjoyed this instructable and that it helped you have an easy, creative, and fun experience while creating your cardboard master piece.

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