Recently, I’ve been using the COB LED lights in multiple projects and have found them versatile and convenient. Below, I wanted to share answers to some of the questions I had before using these parts.
Maker’s Supply Part (product link to US Store: COB LED Strip Light
Q: What is the diameter of the LED strips?
A: The store listing indicates that all three sizes (300, 200 & 100mm) are 1mm in diameter. In practice, I find that that the diameters are closer to:
- 1.9mm for the 300mm LED
- 1.6mm for the 200mm and 100mm LEDs
Q: How can the LEDs be attached to prints?
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Within a tube: for applications without significant movement, I’ve found this to be a stable method. In the GIF below, I had run the LEDs through a tube and had a small cross-bar over the top. Bending the strip over this bar provided plenty of tension for a stable hold.
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Inset within a channel: when mounting the strips to a surface, I use a Boolean operation to create a channel with a lip that holds the LED in place. Given the rubbery coating, I’ve found that this can create a strong hold. I use these measurements (also included as an STL) for the Boolean object and extrude it into the shape I need:
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300mm (STL of profile geometry)
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200mm (STL of profile geometry)
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This example STL includes channels for both a 300mm and 200mm LED with a pass-through for the PCB to stay hidden in the back. The diameter of the channels is just enough to hold the full length of the LED for each size.
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Magnets: Although I haven’t tried this myself, other users have mentioned using magnets and self-tapping screws such as in this post.
Q: How flexible are the LED strips?
A: I haven’t stressed the components enough to bring them to the point of failure but have bent them to 20 degrees without any issues. Similarly I’ve wrapped them around a cylinder with a diameter of 7mm without causing any failure. Mechanical pencil for scale:
The flexibility of the strips I can allow for them to be placed in tight quarters where wiring could be difficult. Thin this example I’m feeding them through a channel at a 90 degree angle so that all of the wiring can remain contained within a separate space.
Q: Is light emitted evenly around the surface of the strip?
A: The actual LEDs all face a single direction but the rubber material diffuses the light. I don’t have a way to measure this accurately but would estimate that the back side is around 75% the brightness of the front.
Because the light is diffused, I find that these LEDs can be a good solution for providing light across a large area vs. using several smaller, directional lights. In this example a single LED is providing light behind many small windows on two sides of an object:
Q: Are these suitable for moving parts?
A: Maybe but in my use cases, I have needed to be cautious of any movement of the LED strip or wires leading to it. At first I thought there was a short in the SH 1.0 wires I was using but have seen the same flickering behavior across multiple wires, power distribution boards and potentiometers.