Electronics > Repair
How to desolder wire looped through terminal lug
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matthuszagh:
I have to remove the wires from the lamp, shown in the attached image. The end of the wire has a u-bend that has been inserted into a hole in the terminal and then soldered. In the past I've used one of two approaches:

1. Cut the wire near the connection and remove the solder and wire piece after. Then, if I need to resolder the wire to the terminal, I (optionally) cut off any remaining length of the wire with solder and strip some insulation. This process shortens the wire somewhat.
2. I apply heat with a soldering iron to the connection and attempt to pull the wire out. This can be a bit tricky because of the u-bend in the wire.

It seems like option 1 is generally better since it places less mechanical stress on the connection and is easier (I've sometimes had trouble getting option 2 to work). Also, it's probably preferred to cut the end of the wire anyway to expose wire without solder to be able to create a u-bend for the next connection.

Thoughts? What do other people do?
Kim Christensen:
If the wire has insulation with a really low melting point, I usually just cut if off and then extract the remainder. Otherwise it just becomes a melted mess.
If the wire is heat tolerant, I'll try applying heat to the joint and do a 90 degree unwrap of the wire. Then if it's not wrapped very well then a push on the wire while the solder is molten can dislodge it.
But in all cases it always depends upon the situation. If there's a ton of spare wire, or the wire is easily replaced, then I'm simply cutting it off.
coppercone2:
Haha

I have seen one that was tied in a knot and then soldered on the connector

I am not too careful with them, because the truth is that if it breaks from minor forcing, you should be happy you found a weak connector. If you ever solder a fresh one it gives you a  good idea of how much stress it should be able to take.

I notice some break really easily, but I think that is often a sign of corrosion, and you should not beat yourself up if they break since they are damaged. Its probobly the same old story with the corrosive flux
Ian.M:
OTOH, it is usually highly desirable to preserve the connector or other part with the terminal lug.  Back in the day, the insulator was usually phenolic or other heat resistant plastic, but nowadays, all the cheaper end of the market uses injection moulded thermoplastics so you absolutely cannot afford the time at temperature required to unpick the looped wire without damage unless the part is already faulty, so is to be replaced anyway.  Wire can be replaced or spliced fairly easily if enough slack cant be found, and most of us already have materials to do so handy, but sourcing and fitting a panel mount part is a PITA, especially when it is important to avoid marring the panel.

I therefore would favour cutting the wire right at the lug unless the part is faulty and the wire has little slack, which will make me cut the  terminal off to free the wire from the hole so it can be desoldered without wire damage.
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