How to Draw a Flex Duct
- 1). Draw a circle. This is the outside rim of the opening of the flex duct.
- 2). Draw a circle inside the circle you drew in step 1. This is the inside rim of the opening of the flex duct. You have just drawn the opening of the flex duct.
- 3). Draw a line from the top of the opening to the end of the tube, then draw a line from the bottom of the opening to the end of the tube. You have just drawn the body of the tube.
- 4). At the opposite end of the tube from the opening, draw a curved half circle connecting the top of the tube to the bottom of the tube. This circle should mimic the shape of the opening of the flex duct. This is the rear opening of the flex duct.
- 5). Shade the interior of the tube with a series of lines inside the tube that mimic the shape of the opening of the tube. The lines should grow darker and closer together as they recede inside the tube.
- 6). Add texture to the exterior of the duct by drawing a series of lines distributed from the front to the back of the tube. These lines should be relatively evenly spaced and should mimic the shape of the opening of the tube (they should be half-circles, showing the curvature of the tube).
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