LED Light Strip Cutting Loses Continuity

Discussion in 'The Projects Forum' started by Sparkypine, Jan 3, 2014.

  1. Sparkypine

    Thread Starter New Member

    Jan 3, 2014
    1
    0
    I've purchased 4 rolls of single color/white non-waterproof 5050 LED's and did my kitchen cabinets. Everything went great. I soldered my own wires on each contact after cutting and tied everything together with a power supply and was happy as a clam. Feeling confident in the procedure, I offered to do my mother's kitchen cabinets. Ordered up two more rolls, measured, cut, soldered, connected...did not work. Finally traced it to lack of continuity on the strips. Thinking my soldering job was bad, I tried it again, still no continuity.

    Finally, I figured out that the strips somehow lose continuity on one contact after I cut them...no matter how carefully I cut on the given line. In fact, I can put one probe of my tester on the positive or negative side down the strip, and then up the strip and my tester happily beeps. Once I cut, however, one side loses it if I touch the probe on the cut contact. The copper contact surface looks fine and unblemished. I don't see any separation of the strip where I cut. I just don't get it. The strip came with pre-soldered wires on each end so I used those just to get the job done, but I have a lot of wasted strip now.

    Has anyone seen this before? It's not like I haven't done this before. I'm sure it could just be a bad batch of strips but I'd like to get down to the root cause since I'd still like to do few more projects.
     
  2. wayneh

    Expert

    Sep 9, 2010
    12,087
    3,026
    I think anyone that might help will need brand and model numbers, and/or good photos.
     
  3. Metalmann

    Active Member

    Dec 8, 2012
    700
    223
    "In fact, I can put one probe of my tester on the positive or negative side down the strip, and then up the strip and my tester happily beeps. Once I cut, however, one side loses it if I touch the probe on the cut contact. The copper contact surface looks fine and unblemished. I don't see any separation of the strip where I cut".



    I've bought quite a few of those strips, but never had that problem. However, I had a bad solder joint at the end of one.
    Didn't peel off enough plastic like I thought I had...,.

    Some of those waterproof joints take time.
     
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