We love our bike lights, but they shine such a small, intense light. We have expanded the visiblity of a rear bike light. We use the translucent material of a milk bottle to diffuse light across a wider space. We've checked to make sure it does project enough brightness at a distance to keep a rider safe. Better yet, the design is surprisingly fun and seems to put all road users in a friendly mood :)
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Step 1: Materials
You will need:
- A translucent bottle. We used a plastic milk bottle.
- A marker
- A cutting blade
- A red bike light. A tube-shaped bike light with ridges is best.
- Old nylon stockings or cable ties.
- A bicycle with a rear rack.
Step 2: Insert the Bike Light Into the Bottle Lid
- Rest the bright end of the bike light against the top of the lid. Trace around the light with the marker.
- Using your cutting knife, cut a hole at least 5mm smaller than the circle you just traced. You want the bike light to fit snugly in the hole, so it's best to start small.
- Test inserting the bright end of the bike light into the top of the lid. Enlarge the hole as needed. It's easier to get the bike light to sit snugly if the light has ridges along it's body.
- When the bike light is secure, screw the bottle lid onto the bottle.
Step 3: Position the Diffuser on Your Bike
- Hold the bottle horizontally along your bike's rear rack.
- Note where the vertical bars of the rack meet the horizontal tray of the rack. These bars will help straps from sliding along the rack.
- Mark points on the bottle for straps to wrap under the rack, using the bars as anchors.
Step 4: Optional: Make Nylon Straps
If you are using old nylon stockings as straps, cut the stockings into 1 inch strips. Combine strips as needed to make the length of strap you need. Remember to account for the stretch in the stockings!
To combine the strips:
- Place two strips down, one overlapping the other
- Take the part of the strip that is being overlapped, and fold it in half lengthways (out towards the other end of that strip, over the overlapping strip)
- Continuing to hold the strip, slide it under the opposite end of the same strip.
- Pull both 'ends' until the knot in the middle is snug
Step 5: Attach Straps
- Cut small holes where you marked them on the body of the bottle.
- Thread nylon straps or cable ties through the holes.
Step 6: Attach the Diffuser to Your Bike
- Lay the bottle horizontally along your bike rack.
- Wrap the straps under the rack.
- Tie the staps off to the side (so the ends don't interfere with your bike wheel).
- Trim the ends of the straps if needed.
Step 7: Test Brightness of the Light
Where we live, there are regulations on how bright a light needs to be over a distance. In our case, the rear red light needs to be visible from 200 metres.
To test this, we mounted the light diffuser on our bike and viewed it in the dark 200 metres away. It passed the test! Our light is also more visible from the side than regular lights.
Note: If your light is not visible from far enough away, you can cut a hole in the base of the bottle. This will allow more light to project behind you, but the diffuser will be less bright when viewed from the side.
Step 8: Ride Out!
Enjoy your new bike light diffuser! We hope you have as much fun using it as we have.
Recharging your light is easy. Unscrew the bottle cap (with the light in it) for easy access to your bike light.