# Soldering off a motherboard?



## Redherring19

I am looking to buy a soldering iron/gun (~£30) for repairing a charger port on a laptop motherboard (and also other tasks). Previously, I tried using a 30W iron to de-solder, but it did not even melt the solder (I'm guessing laptop companies use high grade (lead free?) solder in manufacturing, so has a higher melting point). I have been looking at this one: http://www.amazon.com/Weller-D550PK-120-volt-Professional-Soldering/dp/B00002N7S1 but not sure if 200W for a laptop could be risky...

...please recommend a soldering iron/gun that you see fit for the task I have listed


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## tremmor

Sorry.....its risky business. SMT will be your nightmare. mine was $150.00 15 yrs ago. temp controlled, grounded. Don't do it. will be your nightmare without proper equipment. You will short it out. Mine was a Weller, pencil soder iron.


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## Redherring19

What do you recommend I do then?


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## Hyper-Threaded

You can do it with the 30w. Just keep constant tip pressure to the solder, wait for it to warm it up, and it will melt. Might just take 2min.


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## cjmarsh81

Something wrong if it doesn't get hot enough to melt solder.  Give it a few minutes to heat up.

SMD soldering is very difficult and risky.  Head the board up too much and you could damage components.  Just be careful not to heat up the area too much.

I don't think too many people do component level repair anymore.  So if the laptop isn't charging then go for it.  You will either fix the laptop or break it irreperably, which means you are back where you are and it was worth a shot.


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## strollin

You also need to make sure the soldering iron tip is properly "tinned".  This involves melting some solder on the tip then wiping it on a pad to spread the solder and remove excess solder so that there is just a thin layer of solder left on the tip.

After you place the iron on the component you wish to desolder, hold it there then take a little bit of solder and touch it to the tip to get the solder to flow which should help transfer heat to the solder joint you are attempting to desolder.  Make sure you have a solder removal tool such as a wick or a bulb (I prefer a bulb).  Take your time and don't let the joint get too hot or you will burn the board and start lifting traces.  It may take several cycles of melting the solder and removing it with the bulb to remove enough solder to remove the component.  If there are components nearby on the board that may get damaged from the heat you can give them a little protection by clipping something like an alligator clip to the component to act as a heat sink.

30-35W should be enough to work on a PC board, 200W is too much and is asking for trouble.  Instead of the soldering gun I would consider something like this: http://www.amazon.com/Weller-WLC100-40-Watt-Soldering-Station/dp/B000AS28UC/ref=sr_1_1?s=hi&ie=UTF8&qid=1360162930&sr=1-1&keywords=weller+soldering+iron.  I have a Weller soldering station that my wife bought for me about 35 years ago that I still use today.

You may also consider taking the laptop to a shop and let them fix it for you.  Put the money you would spend on a new soldering iron toward that repair.  A properly equipped shop will have a desoldering station which uses hot air and does the job quickly with less chance of damage to the board or other components.  If you attempt the repair yourself and botch it, a shop may not be able to fix it and you will then need to replace the motherboard.


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## tremmor

30 watt is way, way to much. Mines like 10 watt or and 15 watt and maybe lower. The tip is wide as a needle. Ive done before. It tracked across and older board then had another mess. but fixed it. that was years ago. Tinning the tip was a good call but still risky unless you have experience.


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## PohTayToez

cjmarsh81 said:


> Something wrong if it doesn't get hot enough to melt solder.  Give it a few minutes to heat up.
> 
> SMD soldering is very difficult and risky.  Head the board up too much and you could damage components.  Just be careful not to heat up the area too much.
> 
> I don't think too many people do component level repair anymore.  So if the laptop isn't charging then go for it.  You will either fix the laptop or break it irreperably, which means you are back where you are and it was worth a shot.



My iron goes up to about 470C/900F and sometimes it won't melt solder on what I'm working on.  What you want to do is take some of your own solder that melts at a lower temp and apply it to the solder on the board.  It will help transfer the heat and when it mixes in it will make it melt easier.  

For a power jack though I would recommend using a heatgun with a small tip if there are not any surface mount component too close to the jack.  Either way though a power jack repair will be pretty difficult if you have not done this sort of soldering before.


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