# How to Make a Cardboard Clam Hat

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This costume was made for a Technology project in my high school.  The task was to make a marine-themed costume out of cardboard for a middle schooler to use at a play or during Halloween.  The costume had to utilize slotted construction and couldn't make use of fasteners and/or adhesives.

Design Brief:
Design and build a marine-themed costume out of recyled cardboard.
Must not use fasteners and/or adhesives and utilizes slotted construction.

Specifications:
-Marine-themed
-Easy assembly
-Slotted construction
-Play or Halloween

Limitations:
-Only recycled cardboard
-Middle school student
-As few parts as needed

Supplies List:
Supply          Quantity              Size
cardboard         1                  30''x30''

Tools List:
Tool               Tool Number                   Purpose
Pencil                     T1                Drawing
Utility knife             T2                Cutting cardboard
Cutting board        T3                Protecting surface when cutting
Ruler                       T4                Measuring distances

Parts List:
Part                    Part Number          Quantity
Lower shell                P1                         1
Upper shell                P2                         1
Connector                  P3                          1

### Teacher Notes

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## Step 1: Making the Lower Shell

1.    Lie the cutting board (T3) on a flat surface.
2.    Put cardboard (S1) on top of cutting board (T3).
3.    Use pencil (T1) and ruler (T4) to draw a circle with a diameter of 22 cm.
4.    Use utility knife (T2) to cut circle out of the cardboard (S1).
5.    Use pencil (T1) and ruler (T4) to draw a circle with a 22 cm circumference.
6.    Use utility knife (T2) to cut out the circle.
7.    Use utility knife (T2) to cut from sides of lower shell (P1) to bottom.
8.    Cut a 4.5 cm tab in bottom of lower shell (P1) with utility knife (T2).
9.    Make a 1 cm long cut on both sides of the tab with utility knife (T2).
10.  Make an angled 4.5 cm long slot a half centimeter away from the previous cuts with utility knife (T2).
11.  Fold edges if wanted.

## Step 2: Making the Upper Shell

1.    Use pencil (T1) and ruler (T4) to draw a circle with a diameter of 22 cm.
2.    Use utility knife (T2) to cut circle out of the cardboard (S1).
3.    Use pencil (T1) and ruler (T4) to draw a circle with a 22 cm circumference.
4.    Use utility knife (T2) to cut out the circle.
5.    Use utility knife (T2) to cut from sides of upper shell (P2) to bottom.
6.    Make a 5 cm wide, 1 cm long cut 2 cm away from bottom of upper shell (P2).
7.    Make a 5 cm wide, 2 cm long cut 1.5 cm away from the previous cut.
8.    Fold edges if wanted.

## Step 3: Making the Connector

1.    Use pencil (T1) and ruler (T4) to draw a 4'' x 5'' rectangle in cardboard (S1).
2.    Use utility knife (T2) to cut rectangle out of cardboard (S1).
3.    Use utility knife (T2) to cut a 3'' x 1'' section from bottom of connector (P3).
4.    Cut a 2'' x 1/4'' slot 3/8'' above the previous cut with utility knife (T2).
5.    Cut a 2 1/8" x 2 1/4" tab 5/8" away from previous cut using utility knife (T2).
6.    Cut to the end of the tab from 3/8" down from the top and 1/8" into the tab with utility knife (T2).

## Step 4: Assembly Pt. 1

(Note: Start this step with the upper shell's outside face on bottom)
1.    Insert connector (P3) tab into larger slot on upper shell (P2).
2.    Insert connector (P3) tab into smaller slot from other side.
3.    Repeat Step 1.

## Step 5: Assembly Pt. 2

Insert connector (P3) legs into lower shell's (P1) slots: lower shell tab goes into connector slot, connector legs go into lower shell's side slots.