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I have an Epihpone (Les Paul 100, fairly standard) electric guitar, which over the years have gotten to suffer from a non-functioning bridge pickup. I verified this using an ohm-meter, the result being that only the neck pickup gave a signal (also apparent from plugging it into my amplifier and playing) at 20K. In order to repair it or replace it, I am attempting to disconnect it from where it is soldered on; at its volume-meter (see pictures at the bottom).

I did attempt to remove the solder by heating it and the surrounding area, and use a solder sucker, but the solder would not melt - even after prolonged exposure to the heat from the soldering iron (30W, fairly standard). My question is, would I be better off using a solder gun? Clearly it gives off more temperature, hence making it easier to melt the solder, but I am somewhat concerned of also harming the nearby wiring (which mostly are not long enough to cut and re-solder on).

I made sure to let the iron reach peak temperature and to tip it with some solder beforehand, but the solder barely melted. I guess an alternative would be to cut the wire rather than melt the solder, but I would at any rate have to re-solder a new one on at some point.

Any suggestions on the optimal way of getting rid of this piece of solder would be appreciated.

Epihpone Solder Joint 1 Epihpone Solder Joint 2

Appendix: Results

I did the following:

  1. Used a 175W solder gun to melt away enough solder to get a better hold of the wire.
  2. Cut the black (hot) wire as close to the solder joint as I could.
  3. Used the 30W solder iron (pointy tip) to melt away more around the remaining two black wires (bottom of picture 1).
  4. Cut as close as possible to the joint for these two as well.
  5. Melted the smaller solder joints for the white wire and red wires, allowing them to be pulled away.

In total I lost only 4-5 millimeters of wire from the pickup, and slightly toasted a few nearby wires, but not so badly that they took any substantial damage. Also, I tested the pickup (directly on the wires of the detached unit with 20K ohm) which showed that in fact the pickup is functional, giving ground to assume some fault with some other wire, part, or joint. At any rate, replacing the volume-meters and tone-meters is not costly, and re-soldering them should yield better connections.

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migrated from diy.stackexchange.com Dec 17 '13 at 12:31

This question came from our site for contractors and serious DIYers.

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The problem you are facing is that 30W can't produce enough heat to melt solder that is in contact with a lot of metal and consequently works as a heatsink.

Best option is to buy a temperature controlled soldering iron that has a higher wattage, the advantage of that is it can reheat the tip very fast when it detects that the temperature is dropping by providing 50w or 70W or even more (depends on the model).

The cheap alternative is the heat gun which is powerful enough to melt the solder but has no temperature control so it's up to you to control the applied heat.

My suggestion if you intend to use the heat gun is to put some solder paste (avoid inhaling the fumes) on the solder you want to remove which will help it melt when heated, place a desolder braid over the solder and heat it with the gun from the opposite side (The order is I mean is in layers from bottom to top : solder / paste / braid / soldering iron , in a sandwich fashion). This way you will be able to remove the solder little by little without overheating too much the surroundings by sucking the solder in the braid as soon as it melts .

Finally there is always the despair solution which is to cut the wires as close to the end as you can and resolder them to the new plug (assuming they are long enough)

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  • 1
    \$\begingroup\$ +1 for "more watts & solder braid", also I'd suggest just buying a new pot for $5 before the legs fall off due to flexing / heat cycling etc. \$\endgroup\$ – John U Dec 17 '13 at 15:10
  • \$\begingroup\$ I did not have the time to stop by the hardware shop before going ahead, but I followed a combination of the answers here, and will add an appendix to my question summarizing the method. \$\endgroup\$ – OleVik Dec 17 '13 at 17:29
  • \$\begingroup\$ And I add flux to my desoldering braid. It only helps. Also keep a spare pot on hand because they don't love heat torture (ask me how I know) \$\endgroup\$ – HL-SDK Dec 17 '13 at 17:49
  • \$\begingroup\$ A couple of the pots already showed sign of tear and slight bending on one (dropped the guitar a few times over the years), so I ordered some spares to replace them. I assume they don't really handle heat well, but can they become useless from a bit of excessive soldering on top? \$\endgroup\$ – OleVik Dec 18 '13 at 18:46
  • \$\begingroup\$ @OleVik Some cables have insulator materials that are more sensitive to heat than others so it depends on the type used. \$\endgroup\$ – alexan_e Dec 18 '13 at 19:21
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You do need a bigger iron, but I too would be nervous about going for the gun - they aren't temp controlled and tend to make a mess of things if you aren't extremely careful.

See if you can find a friend with an iron with higher output and temperature control - that's what you really need. Alternately, you can buy a better iron. If you do, make sure to get something with temperature control and 50-70W of output.

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The tip on the iron will make a difference; to tranfer lots of heat, you need a nice, wide tip. If you're using quite a pointy tip, try swapping it for a chisel-type tip (or similar).

Another option might be to try desolder braid (or some stranded copper wire) to remove the solder in preference to the solder sucker.

Personally, I'de be tempted to try the solder gun, but while taking care not to over-cook things. Do it in short bursts and let things cool off a while in between if necessary.

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