I have two CPU fans which have been damaged. In one the wires were separated in the middle, in the other they were separated at the solder contacts. I have very little soldering/wiring experience, how difficult would it be to repair these and what would be the best technique to do so? Standard size fountain pen included for scale. For reference these are Phanteks PH-F140HP fans.

Number 1:

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Number 2:

enter image description here

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    \$\begingroup\$ You could either buy a micro soldering station and get soldering or ask a friend/ pay someone to do it for you. This was once soldered by humans, it can be done once again. \$\endgroup\$ Commented Jun 18, 2018 at 4:09
  • \$\begingroup\$ It can be done with a regulat hobby soldering iron, a fine tip, and a steady hand. Pre-tin the wires. Then inhale, solder to the board, exhale. \$\endgroup\$
    – dim
    Commented Jun 18, 2018 at 5:46
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    \$\begingroup\$ +1 for good quality photo's plus size reference. \$\endgroup\$
    – Oldfart
    Commented Jun 18, 2018 at 5:49

2 Answers 2


Match and mark Wire positions ,
clean old solder joints with vacuum solder sucker tool or gauze wire to absorb solder and
clean out plated thru hole.

Mark wire with ink for pin 1 so ensure same as original connections.
Separate and cut wire to staggered length with 2cm incrments.
Strip insulation to 1 cm so exposed wires do not touch adjacent joints.
Twist single pairs tight with fingers and some dexterity then solder and repeat for next.

Solder as in https://www.youtube.com/watch?v=aoD2aUvnQXg after 13:40.

Then insulate with Kapton tape or clear packing tape or similar

For brittle solder wire on PCB , I use polyurethane subfloor adhesive from a caulking gun to make a plastic strain relief and mold some gunk around solder joint on board to prevent future failures after testing. 24 h cure.

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    \$\begingroup\$ +1 for strain relief - stop this happening again. \$\endgroup\$
    – Criggie
    Commented Jun 18, 2018 at 11:27
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    \$\begingroup\$ It appears to be good quality stranded tin plated copper, acc. to EN 60228, class 5 ... But it feels like 50 yrs since I used a good old fountain pen. \$\endgroup\$ Commented Jun 18, 2018 at 12:35

Soldering on the circuit board of the fan is not a simple task. You have to be careful not to harm the plastic (it can even melt on the soldering pads, making soldering much more difficult) nor soldering the solder pads together.

If you would like to repair your fan on your own, first find an old (made in 1998 or later) walkman, diskman, or computer CD/DVD drive, de-solder some wires and then re-solder them. This can give you some practice, which you will definitely need. (You may also use an old (also 1998+) VSH or DVD player, or a radio, but these devices contain high voltage parts, and some capacitors may contain high voltage even after years.) After you gained some practice, find or buy some old/cheap/crappy PC fans, de-solder the wires and re-solder them.

If you are unsure about how to repair your fan, bring it to a computer service. They will kindly solder it for you for about 5-10USD.


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