​How to Repair Broken or Torn Flex / Flexible Cables.

Introduction: ​How to Repair Broken or Torn Flex / Flexible Cables.

Actual size of cable was 3/8 of an inch wide!

Step 1: Repairing Broken Flex Cable for Electronics Equipment

  1. Images below contains all Steps and instruction to Repair Flexible Cables
  1. Repairing broken flexible cables, Image is oversized to show detail.
    Tools and Supplies Required: Solder Paste, Scissors, Soldering Iron, Solder Wick, Masking Tape, Single Edge Razor Blade, Flat Blade Screw Driver

Step 2:

  • Step 2: With Scissors cut straight the torn section completely to from two straight edges.
  • OR
  • If cutting would remove too much length, while more difficult, cut or tear as straight as
  • possible the un-torn area to get two halves. Then follow the instructions below.

Step 3:

Step 3: With Single Edge Razor Blade scrap the top side of one half of cable, expose bare copper. Be careful not to remove copper as it may break off, Take your time! It is a slow process. Then turn over second half of cable to the back side the and scrap it to expose bare copper. About 1/8 to 3/16 inch is all that is necessary on each half. Obviously you will not be able to scrap the traces as precisely as the images.

Step 4:

Step 4: With copper sides up spread a thin layer of solder paste across all exposed copper
Do not worry about getting it on other parts of cable. Using a soldering iron heat the paste so it adheres to the copper part of cable. Do this to both sides. Any remaining paste should be cleaned off at this point with a solvent or cleaner be careful to not wipe too aggressively on copper so as to not release it from the plastic. With solder a wick go over the soldered copper and remove excess solder surface should have just a thin layer when done.

Step 5:

Step 5: Using Masking Tape, tape down securely the top exposed foil side first.They lay the copper side down half over the edge to the tape lining up as perfect as possible overlapping about 1/8 of an inch, apply masking tape as well to hold in place. Apply a small amount of solder paste at the junction of the two pieces. Heat up the top foil until some of the solder paste is pull under the two layers. Then using a flat blade screw driver or razor blade hold the top layer down while sliding off the soldering iron and putting blade in it's place until solder is cooled 30 seconds. Check connections if Okay clean up any remaining solder paste. If the joint does not look good reheat and separate the two layers and repeat process as necessary. If too much solder use solder wick to remove if not enough apply more solder paste and reheat joint as before.

1 Person Made This Project!


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5 months ago

hello, can i just tape it together with a regular scotch tape if i dont have a soldering iron and paste?

thank you so much(✿^‿^)


Reply 4 months ago

you can certainly try! it's possible you'd get it close enough to work.
I know this bc I accidently tore a tiny ribbon cable in my phone while disassembling it to replace the battery and surprisingly noticed that the speaker still worked after putting it back together. that was even without taping it! I obv got super lucky & it lined up just right! Unfortunately at a later date i dropped my phone in water and had to take it apart again and since havent been so lucky.


1 year ago

my repair is inside a DSLR auto-focus lens. The damaged portion of the flex circuit has 5 straight-through traces, but is severed in two places. I'm afraid if I repair this item using instructions here, it is brittle enough to break again. Is there a good way to extend (or add new material) to my severed flex circuit?


Reply 1 year ago

you can get some "magnet wire" and carefully position and tape down each to align with the flex cable, then solder. It takes a bit more work but you can extend the flex to any length you like.

Just be sure that the gauge of magnet wire is not too big and remember to strip the enamel from the ends before you try to solder.


2 years ago on Step 1

u need soldirality ability forget to add from step1