Materials required –
1x Foam of size 9 x 1.75 x 1 inches (or what suits your head size)
1x A4 OHP sheet of 100 micron or higher (175, 250, 400 microns)
1x Elastic of 12 inches
1x 2-way paper thin tape
1x Scissor
1x Ruler (Scale)
1x Stapler
1x OHP marker
1x Candle (optional)
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Step 1: Put one side of 2-way paper thin tape on one side of the foam as shown in image 2 below.
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Step 2: Cut the OHP sheet edges on two sides at the bottom as shown in Image 3 (below).
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Step 3: Stick the foam in center of top edge of OHP sheet after peeling the other side of 2-way tape.
Step 4: Cut the Elastic band you have to get a length of 12 inches – without stretching. You change the size according to your comfort.
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Optional step: Use the candle to solidify the edges of Elastic so that threads don’t mess around.
Step 5: Staple the edges of Elastic band on OHP sheet to either sides of foam, as shown in the main image.
Note: You can make changes to this design. It is an open source design and used worldwide, including Ford & Nike in USA and Mahindra in India. Everyone has modified the design slightly as per their expertise.