Author Topic: How to Remove Solder that Won't Melt?  (Read 11741 times)

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Offline superscott319

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How to Remove Solder that Won't Melt?
« on: August 17, 2013, 01:20:40 PM »
Even as a beginner, this is pretty bad.  :palm: So I'm working on my first real electronics project which involves desoldering a number of components from a PCB and soldering on new ones. I've since realized what some of my mistakes were such as using cheap solder which was also too thick. I'm not sure what went wrong with the desoldering process but getting the solder to become molten so my solder sucker and wick could remove it was very difficult. Eventually I was able to remove all the old solder but not without making a mess of the board. Adding more solder only made it worse.

Right now I'm trying to clean the existing solder off the board but can't get it to melt even when setting my iron to a high temperature. Applying solder wick doesn't absorb it. Maybe all the flux burned off and that's causing it not to melt? What would be the best way to clean up a PCB that's been badly soldered like this?



Thanks for any advice.  :)
« Last Edit: August 17, 2013, 01:23:26 PM by superscott319 »
 

Offline c4757p

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Re: How to Remove Solder that Won't Melt?
« Reply #1 on: August 17, 2013, 01:40:35 PM »
Jesus tap-dancing Christ, that poor, poor PCB! :wtf:

My suspicions: 1) "High temperature" ain't as high as you think. 2) Corroded tip - not making good contact with the solder to transfer heat. 3) Lead-free solder was brought to this world by Satan himself. Try cleaning the tip with a gentle brass brush or a wet sponge and lots of flux and fresh solder, then clean the board with isopropyl alcohol, then flood the board and the solder wick with liquid flux. Try again.

Looks like you may have ripped up a couple pads. If so, sand/scrape away the solder mask around them to expose the copper, then repair with wire.

If your soldering iron is a $10 RadioShack special, then my diagnosis is "fucked".
« Last Edit: August 17, 2013, 01:43:37 PM by c4757p »
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Offline superscott319

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Re: How to Remove Solder that Won't Melt?
« Reply #2 on: August 17, 2013, 02:08:12 PM »
Jesus tap-dancing Christ, that poor, poor PCB! :wtf:

My suspicions: 1) "High temperature" ain't as high as you think. 2) Corroded tip - not making good contact with the solder to transfer heat. 3) Lead-free solder was brought to this world by Satan himself. Try cleaning the tip with a gentle brass brush or a wet sponge and lots of flux and fresh solder, then clean the board with isopropyl alcohol, then flood the board and the solder wick with liquid flux. Try again.

Looks like you may have ripped up a couple pads. If so, sand/scrape away the solder mask around them to expose the copper, then repair with wire.

If your soldering iron is a $10 RadioShack special, then my diagnosis is "fucked".

I'm using a decent quality soldering station (X-Tronic 4010) that cost about $80 and even when raising the temperature to it's max setting, 480c, the blobbed solder shown in the picture still won't melt. There is what appears to be some corrosion on my tips so that could be the cause. As for the solder, I'm using some cheap unnamed stuff that came along with a PC repair kit so it could possibly be lead-free.

I will try your suggestion of cleaning the tip and board although I'll need to order those items. What kind of flux would you recommend for cleaning a soldering tip and the board? Would flux pen or the brush on kind work better?

Thanks once again for the help.
 

Offline c4757p

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Re: How to Remove Solder that Won't Melt?
« Reply #3 on: August 17, 2013, 02:19:40 PM »
OK, 480C should be plenty. Though, a warning - not all soldering stations that can be set to 480C can actually maintain that temperature when applied to a large thermal mass.

I have had cheapo soldering tips that disintegrated in lead-free, you might want to try something different. (That ugly blob looks exactly like my first foray into the sadistic hell that is lead-free solder, so I think that's what you've got. Either way, the stuff already on the board is definitely lead free.) I use Kester 44 (eutectic) - don't gasp too much at the price, remember, that's a full pound of it. It's a bit thicker than what Dave and company recommend, but I like it.

Either type of flux will work, and I find both equally convenient, so just get whatever you think you'll prefer. I think you'll find that a lot of things magically start working better with a liberal application of flux :-+
 
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Offline Sigmoid

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Re: How to Remove Solder that Won't Melt?
« Reply #4 on: August 17, 2013, 03:01:39 PM »
I'm using a decent quality soldering station (X-Tronic 4010) that cost about $80 and even when raising the temperature to it's max setting, 480c, the blobbed solder shown in the picture still won't melt. There is what appears to be some corrosion on my tips so that could be the cause. As for the solder, I'm using some cheap unnamed stuff that came along with a PC repair kit so it could possibly be lead-free.

I'm quite certain that the heat isn't getting from the tip to the solder.
My little experience with corroded lead-free is that adding a generous amount of solder to the tip, so you have a gob hanging off, and applied to the problematic joint will eventually get the heat conductance in order and the joint melted.
 

Offline pickle9000

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Re: How to Remove Solder that Won't Melt?
« Reply #5 on: August 17, 2013, 03:11:41 PM »
Kester 44 is excellent solder, I've used it for many many years. There are several things that can be wrong but start with the solder (and I don't mean the solder on the pcb). Can you melt solder you have on hand with your iron? Does the solder smoke? Is the tip silver with solder and is the solder clinging to the surface of the iron? If the solder does not smoke it's not flux cored, if the soldering iron tip is not holding solder and a nice silver colour it's dirty.

Use your solder as a tool, apply a fresh bit to an already soldered joint to get the melting action started. Be quick no "flux smoke" means that you need to speed up. Adding extra flux is good but most professionals I know just use solder unless working on surface mount stuff and then they tend to use other tools (like hot air) to get the job done.

Get in the habit clean tip, fresh solder on tip, if the soldering iron ends up back in its stand then clean tip and retin the tip.

 
 

Offline andyturk

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Re: How to Remove Solder that Won't Melt?
« Reply #6 on: August 17, 2013, 03:12:34 PM »
If your soldering iron is a $10 RadioShack special, then my diagnosis is "fucked".
:-DD
 

Offline G7PSK

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Re: How to Remove Solder that Won't Melt?
« Reply #7 on: August 17, 2013, 07:20:16 PM »
I think that the black around the solder gives it away (looks like soot), your iron is too hot and you are applying heat to the area for far too long. This usually comes down to not enough or no flux, placing the iron to one side in order to see the solder ( a mistake made by many beginners) you should place the tip firmly on top of the joint and not keeping the soldering iron tip clean and not cleaning the joint before hand (there could easily be a coating put over the board after soldering in the factory). Also check that your solder is flux cored I have seen people try to solder with plumbers solder that does not contain flux cores.
 

Offline sub

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Re: How to Remove Solder that Won't Melt?
« Reply #8 on: August 17, 2013, 08:12:39 PM »
My little experience with corroded lead-free is that adding a generous amount of solder to the tip, so you have a gob hanging off, and applied to the problematic joint will eventually get the heat conductance in order and the joint melted.

Do this.  And not just for lead-free, but any time where you want to get heat from one place to another in short order.  Still add some fresh solder so that the joint gets flux, but a blob of solder will touch the joint with far greater surface area than any tip will.
 

Offline tld

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Re: How to Remove Solder that Won't Melt?
« Reply #9 on: August 17, 2013, 10:22:45 PM »
Do this.  And not just for lead-free, but any time where you want to get heat from one place to another in short order.  Still add some fresh solder so that the joint gets flux, but a blob of solder will touch the joint with far greater surface area than any tip will.

Do this, he's right. Also, there's a difference between adding more of the crappy possibly lead-free solder, and adding something like kester 44. Even if you got burned (pardon the pun) adding crappy solder, I'd still add more when you have some decent leaded, first for thermal-transfer from iron to the stuff you want to remove - don't worry abou getting everything in one go - and then for mixing with the old stuff, to get all of it off.

Oh, and leadfree solder isn't the work of the devil. You need a political comitee to come up with something that bad. ;p

tld
 

Offline bookaboo

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Re: How to Remove Solder that Won't Melt?
« Reply #10 on: August 17, 2013, 11:06:21 PM »
Practice practice practice is what you need, I'm willing to bet everyone in the forum hacked something as badly as that when they started off.
Grab some boards that are total scrap, watch a bunch of relevant youtube vids then remove and replace components until you are competent.
 

Offline KJDS

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Re: How to Remove Solder that Won't Melt?
« Reply #11 on: August 17, 2013, 11:29:56 PM »
Is it just me that has no problems whatsoever using lead free solder?

Offline c4757p

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Re: How to Remove Solder that Won't Melt?
« Reply #12 on: August 17, 2013, 11:38:50 PM »
Yes.
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Offline free_electron

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Re: How to Remove Solder that Won't Melt?
« Reply #13 on: August 18, 2013, 12:22:30 AM »
Nobody spotted that this looks like  a computer motherboard with multilayer thick copper ? And he's trying to replace the capacitors ? You can see what looks like the staggered pins of a pci connector top right of the picture.

So, This board is probably 2 ounce copper ground and power planes... So you will need a soldering iron with a high wattage to be able to heat the damn thing to melting point ! Cranking up temperature is not the correct way ! The poor soldering iron simply doesnt have the -oopf- to get that 'heatsink' up to temperature
« Last Edit: August 18, 2013, 12:24:48 AM by free_electron »
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Offline ablacon64

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Re: How to Remove Solder that Won't Melt?
« Reply #14 on: August 18, 2013, 12:24:37 AM »
Yes.

+1! Lead free sucks....

On topic, it's easier to remove solder by adding new solder to the joints. For large, heat dissipating areas, use low melt desolder wire.
 

Offline PA4TIM

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Re: How to Remove Solder that Won't Melt?
« Reply #15 on: August 18, 2013, 12:44:46 AM »
About desoldering. This is one from a series.

And I think you realy need to look at this series about soldering and repair. Also from Pace and made in the 80's but it tells you all the things you need to know and you will see  it handles all the mistakes you now made.

Most important are a good soldering station at the right temp, with the right tip,  that also can hold this temp on boards like yours. .
Good solder and sometimes flux.
The right technique,
Knowing and recognising the board and construction.


I think your board is dead. All solderpads are missing and probably the vias too. So the innerlayers will now be floating
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Offline Stonent

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Re: How to Remove Solder that Won't Melt?
« Reply #16 on: August 18, 2013, 01:53:47 AM »
Lets start a new standard!

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Offline eKretz

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Re: How to Remove Solder that Won't Melt?
« Reply #17 on: August 18, 2013, 03:26:59 PM »
By the description given, it sounds to me like the guy's iron tip is oxidized all to hell and gone. This is blocking the heat transfer from tip to solder and is why the solder won't melt. He needs to scrape/clean the oxidation off the tip and re-tin the tip.
 

Offline Corporate666

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Re: How to Remove Solder that Won't Melt?
« Reply #18 on: August 18, 2013, 04:52:28 PM »
Oh my god!

Not to sound like a jerk, but you really butchered that board.  It's probably trash.  Or at least it's going to be a bitch to repair, and without kicking you while you are down, if your skills and equipment are such that this is your result, I don't think you are going to be able to repair it.

Solder is not magic stuff - nor does it require flux to melt.  It does require flux to flow and stick nicely, but it will melt without it.  If it is not melting, the joint is not coming up to temperature.  Turning up the heat on your iron isn't the solution.  Fixing the heat *transfer* issue is the solution.  I am guessing

-Your iron is not capable of maintaining temperature well.  I know you said it's an $80 iron, but an iron of that price is made for about $8 in parts and sold to a reseller for $25, so it's not likely to really be that high quality. 

-Most likely, I bet you are using the wrong tip.  I looked up your iron online.  Look at this picture

http://ecx.images-amazon.com/images/I/710JxEv7QeL._SX466_.jpg

You need to be using the middle tip - a relatively blunt chisel.  That board has lots of copper pours which will suck the heat away quickly and prevent the solder from reaching melting temp.  You are going nuts with a red hot iron and all that does is locally burn the shit out of the soldermark and traces - and the result is the pic you posted.


To make this work

1) Use the right tip
2) Have your iron set to the right temp
3) Apply liberal amounts of flux so when it does melt, it flows
4) Use an iron that can maintain temp and deliver the heat into the joint
5) Make sure your tip is in good shape
6) PRE HEAT the board!!!! Use a cheap skillet from Walmart to raise the board to 150-200 degrees (F) over ambient, and voila, you just unloaded 150-200 degrees of heating work from your iron


And to put the dickhead hat on again in closing, seriously, if things start to go to shit, next time STOP and figure out what's wrong and fix it, or you'll end up with that mess again!
It's not always the most popular person who gets the job done.
 

Offline true

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Re: How to Remove Solder that Won't Melt?
« Reply #19 on: August 18, 2013, 05:36:00 PM »
By the description given, it sounds to me like the guy's iron tip is oxidized all to hell and gone. This is blocking the heat transfer from tip to solder and is why the solder won't melt. He needs to scrape/clean the oxidation off the tip and re-tin the tip.
Nah, sounds to me like a cheap crap iron that isn't getting up to temperature, and doesn't have the heat recovery / wattage to deal with the copper heatsinking on the board. And looking at the board where he did remove parts, his too high of a temperature (when it worked) wreaked havoc.

superscott319, get a better iron. preheat the board if it has large copper fills. use the proper tip if you aren't already. don't use such high of temperature, it isn't helping you.
 

Offline eKretz

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Re: How to Remove Solder that Won't Melt?
« Reply #20 on: August 19, 2013, 06:28:35 AM »
By the description given, it sounds to me like the guy's iron tip is oxidized all to hell and gone. This is blocking the heat transfer from tip to solder and is why the solder won't melt. He needs to scrape/clean the oxidation off the tip and re-tin the tip.
Nah, sounds to me like a cheap crap iron that isn't getting up to temperature, and doesn't have the heat recovery / wattage to deal with the copper heatsinking on the board. And looking at the board where he did remove parts, his too high of a temperature (when it worked) wreaked havoc.

superscott319, get a better iron. preheat the board if it has large copper fills. use the proper tip if you aren't already. don't use such high of temperature, it isn't helping you.

Obviously that was the initial problem, and for certain the board has been severely damaged by his approach. I was responding to what seemed like the only question I saw: why won't the solder melt now? And again, if it melted well enough when he originally commenced work to use a solder sucker or braid, it was obviously melting solder fine when he started, and now it won't. So what changed?  My guess by that description is a severely oxidized tip. To the O.P.: Is your iron's tip black?
 

Offline superscott319

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Re: How to Remove Solder that Won't Melt?
« Reply #21 on: August 19, 2013, 01:30:07 PM »
OK, 480C should be plenty. Though, a warning - not all soldering stations that can be set to 480C can actually maintain that temperature when applied to a large thermal mass.

I have had cheapo soldering tips that disintegrated in lead-free, you might want to try something different. (That ugly blob looks exactly like my first foray into the sadistic hell that is lead-free solder, so I think that's what you've got. Either way, the stuff already on the board is definitely lead free.) I use Kester 44 (eutectic) - don't gasp too much at the price, remember, that's a full pound of it. It's a bit thicker than what Dave and company recommend, but I like it.

Either type of flux will work, and I find both equally convenient, so just get whatever you think you'll prefer. I think you'll find that a lot of things magically start working better with a liberal application of flux :-+

Being how difficult it was to melt the solder already on the board for desoldering, you're probably right that it's lead-free. I watched a number of how-to videos on how to desolder PBCs and it seemed pretty easy but maybe they were working with lead solder on those joints. The only other two possibilities would be heat from my iron not making contact with the joint or my cheap desoldering pump. Also I'll try that Kester 44 solder out, thanks for the tip.

Kester 44 is excellent solder, I've used it for many many years. There are several things that can be wrong but start with the solder (and I don't mean the solder on the pcb). Can you melt solder you have on hand with your iron? Does the solder smoke? Is the tip silver with solder and is the solder clinging to the surface of the iron? If the solder does not smoke it's not flux cored, if the soldering iron tip is not holding solder and a nice silver colour it's dirty.

Use your solder as a tool, apply a fresh bit to an already soldered joint to get the melting action started. Be quick no "flux smoke" means that you need to speed up. Adding extra flux is good but most professionals I know just use solder unless working on surface mount stuff and then they tend to use other tools (like hot air) to get the job done.

Get in the habit clean tip, fresh solder on tip, if the soldering iron ends up back in its stand then clean tip and retin the tip.

If I apply fresh solder to most of my tips, it will melt and smoke. The ones that show signs of being oxidized have trouble melting fresh solder and none will stick to it. I'll try your advice on adding more solder to a joint to melt it. Would there be any issues with mixing lead solder with lead-free simply for the purpose of trying to get the join molten for desoldering? Also from what I'm reading here buying some supplemental flux to have on hand for such situations will be very useful. I see there's many different types of fluxes available. Which would you recommend for a decent all purpose flux?

I think that the black around the solder gives it away (looks like soot), your iron is too hot and you are applying heat to the area for far too long. This usually comes down to not enough or no flux, placing the iron to one side in order to see the solder ( a mistake made by many beginners) you should place the tip firmly on top of the joint and not keeping the soldering iron tip clean and not cleaning the joint before hand (there could easily be a coating put over the board after soldering in the factory). Also check that your solder is flux cored I have seen people try to solder with plumbers solder that does not contain flux cores.

I was placing my iron on the side of these joints for that very purpose, so I'll be sure to correct that. How can I place the iron firmly on top of joints with tall leads though? Also my solder does have a flux core but I'll be upgrading to some better stuff soon.

Practice practice practice is what you need, I'm willing to bet everyone in the forum hacked something as badly as that when they started off.
Grab some boards that are total scrap, watch a bunch of relevant youtube vids then remove and replace components until you are competent.

Indeed, this board I'm working on came from a broken amplifier that I was trying to repair, and I have a few old PCI cards that I'm practicing on. Oddly enough, desoldering some of these old PCI cards worked out really well for me while this amplifier was much harder. Perhaps they used lead solder on them.

Nobody spotted that this looks like  a computer motherboard with multilayer thick copper ? And he's trying to replace the capacitors ? You can see what looks like the staggered pins of a pci connector top right of the picture.

So, This board is probably 2 ounce copper ground and power planes... So you will need a soldering iron with a high wattage to be able to heat the damn thing to melting point ! Cranking up temperature is not the correct way ! The poor soldering iron simply doesnt have the -oopf- to get that 'heatsink' up to temperature

The board I'm working on in the photos actually came from a broken mini amplifier and components I removed so far are two LEDs and a dual gang volume potentiomoter.

About desoldering. This is one from a series.

And I think you realy need to look at this series about soldering and repair. Also from Pace and made in the 80's but it tells you all the things you need to know and you will see  it handles all the mistakes you now made.

Most important are a good soldering station at the right temp, with the right tip,  that also can hold this temp on boards like yours. .
Good solder and sometimes flux.
The right technique,
Knowing and recognising the board and construction.


I think your board is dead. All solderpads are missing and probably the vias too. So the innerlayers will now be floating

Thanks, I'll take a look at those soldering training videos. As for the board, I figured it's probably dead but it was broken to begin with so that's not a problem.

Oh my god!

Not to sound like a jerk, but you really butchered that board.  It's probably trash.  Or at least it's going to be a bitch to repair, and without kicking you while you are down, if your skills and equipment are such that this is your result, I don't think you are going to be able to repair it.

Solder is not magic stuff - nor does it require flux to melt.  It does require flux to flow and stick nicely, but it will melt without it.  If it is not melting, the joint is not coming up to temperature.  Turning up the heat on your iron isn't the solution.  Fixing the heat *transfer* issue is the solution.  I am guessing

-Your iron is not capable of maintaining temperature well.  I know you said it's an $80 iron, but an iron of that price is made for about $8 in parts and sold to a reseller for $25, so it's not likely to really be that high quality. 

-Most likely, I bet you are using the wrong tip.  I looked up your iron online.  Look at this picture

http://ecx.images-amazon.com/images/I/710JxEv7QeL._SX466_.jpg

You need to be using the middle tip - a relatively blunt chisel.  That board has lots of copper pours which will suck the heat away quickly and prevent the solder from reaching melting temp.  You are going nuts with a red hot iron and all that does is locally burn the shit out of the soldermark and traces - and the result is the pic you posted.


To make this work

1) Use the right tip
2) Have your iron set to the right temp
3) Apply liberal amounts of flux so when it does melt, it flows
4) Use an iron that can maintain temp and deliver the heat into the joint
5) Make sure your tip is in good shape
6) PRE HEAT the board!!!! Use a cheap skillet from Walmart to raise the board to 150-200 degrees (F) over ambient, and voila, you just unloaded 150-200 degrees of heating work from your iron


And to put the dickhead hat on again in closing, seriously, if things start to go to shit, next time STOP and figure out what's wrong and fix it, or you'll end up with that mess again!

This is just one of several old and broken boards I had lying around so I'm using these to practice on. I'll keep all that in mind though. If it's true that this iron isn't capable of maintaining temperature well, would you recommend upgrading to one that can or will proper tip maintenance and technique suffice for now?

OK, 480C should be plenty. Though, a warning - not all soldering stations that can be set to 480C can actually maintain that temperature when applied to a large thermal mass.

I have had cheapo soldering tips that disintegrated in lead-free, you might want to try something different. (That ugly blob looks exactly like my first foray into the sadistic hell that is lead-free solder, so I think that's what you've got. Either way, the stuff already on the board is definitely lead free.) I use Kester 44 (eutectic) - don't gasp too much at the price, remember, that's a full pound of it. It's a bit thicker than what Dave and company recommend, but I like it.

Either type of flux will work, and I find both equally convenient, so just get whatever you think you'll prefer. I think you'll find that a lot of things magically start working better with a liberal application of flux :-+

Being how difficult it was to melt the solder already on the board for desoldering, you're probably right that it's lead-free. I watched a number of how-to videos on how to desolder PBCs and it seemed pretty easy but maybe they were working with lead solder on those joints. The only other two possibilities would be heat from my iron not making contact with the joint or my cheap desoldering pump. Also I'll try that Kester 44 solder out, thanks for the tip.

Kester 44 is excellent solder, I've used it for many many years. There are several things that can be wrong but start with the solder (and I don't mean the solder on the pcb). Can you melt solder you have on hand with your iron? Does the solder smoke? Is the tip silver with solder and is the solder clinging to the surface of the iron? If the solder does not smoke it's not flux cored, if the soldering iron tip is not holding solder and a nice silver colour it's dirty.

Use your solder as a tool, apply a fresh bit to an already soldered joint to get the melting action started. Be quick no "flux smoke" means that you need to speed up. Adding extra flux is good but most professionals I know just use solder unless working on surface mount stuff and then they tend to use other tools (like hot air) to get the job done.

Get in the habit clean tip, fresh solder on tip, if the soldering iron ends up back in its stand then clean tip and retin the tip.

If I apply fresh solder to most of my tips, it will melt and smoke. The ones that show signs of being oxidized have trouble melting fresh solder and none will stick to it. I'll try your advice on adding more solder to a joint to melt it. Would there be any issues with mixing lead solder with lead-free simply for the purpose of trying to get the join molten for desoldering? Also from what I'm reading here buying some supplemental flux to have on hand for such situations will be very useful. I see there's many different types of fluxes available. Which would you recommend for a decent all purpose flux?

I think that the black around the solder gives it away (looks like soot), your iron is too hot and you are applying heat to the area for far too long. This usually comes down to not enough or no flux, placing the iron to one side in order to see the solder ( a mistake made by many beginners) you should place the tip firmly on top of the joint and not keeping the soldering iron tip clean and not cleaning the joint before hand (there could easily be a coating put over the board after soldering in the factory). Also check that your solder is flux cored I have seen people try to solder with plumbers solder that does not contain flux cores.

I was placing my iron on the side of these joints for that very purpose, so I'll be sure to correct that. How can I place the iron firmly on top of joints with tall leads though? Also my solder does have a flux core but I'll be upgrading to some better stuff soon.

Practice practice practice is what you need, I'm willing to bet everyone in the forum hacked something as badly as that when they started off.
Grab some boards that are total scrap, watch a bunch of relevant youtube vids then remove and replace components until you are competent.

Indeed, this board I'm working on came from a broken amplifier that I was trying to repair, and I have a few old PCI cards that I'm practicing on. Oddly enough, desoldering some of these old PCI cards worked out really well for me while this amplifier was much harder. Perhaps they used lead solder on them.

Nobody spotted that this looks like  a computer motherboard with multilayer thick copper ? And he's trying to replace the capacitors ? You can see what looks like the staggered pins of a pci connector top right of the picture.

So, This board is probably 2 ounce copper ground and power planes... So you will need a soldering iron with a high wattage to be able to heat the damn thing to melting point ! Cranking up temperature is not the correct way ! The poor soldering iron simply doesnt have the -oopf- to get that 'heatsink' up to temperature

The board I'm working on in the photos actually came from a broken mini amplifier and components I removed so far are two LEDs and a dual gang volume potentiomoter.

 

Offline superscott319

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Re: How to Remove Solder that Won't Melt?
« Reply #22 on: August 19, 2013, 01:30:30 PM »
About desoldering. This is one from a series.

And I think you realy need to look at this series about soldering and repair. Also from Pace and made in the 80's but it tells you all the things you need to know and you will see  it handles all the mistakes you now made.

Most important are a good soldering station at the right temp, with the right tip,  that also can hold this temp on boards like yours. .
Good solder and sometimes flux.
The right technique,
Knowing and recognising the board and construction.


I think your board is dead. All solderpads are missing and probably the vias too. So the innerlayers will now be floating

Thanks, I'll take a look at those soldering training videos. As for the board, I figured it's probably dead but it was broken to begin with so that's not a problem.

Oh my god!

Not to sound like a jerk, but you really butchered that board.  It's probably trash.  Or at least it's going to be a bitch to repair, and without kicking you while you are down, if your skills and equipment are such that this is your result, I don't think you are going to be able to repair it.

Solder is not magic stuff - nor does it require flux to melt.  It does require flux to flow and stick nicely, but it will melt without it.  If it is not melting, the joint is not coming up to temperature.  Turning up the heat on your iron isn't the solution.  Fixing the heat *transfer* issue is the solution.  I am guessing

-Your iron is not capable of maintaining temperature well.  I know you said it's an $80 iron, but an iron of that price is made for about $8 in parts and sold to a reseller for $25, so it's not likely to really be that high quality. 

-Most likely, I bet you are using the wrong tip.  I looked up your iron online.  Look at this picture

http://ecx.images-amazon.com/images/I/710JxEv7QeL._SX466_.jpg

You need to be using the middle tip - a relatively blunt chisel.  That board has lots of copper pours which will suck the heat away quickly and prevent the solder from reaching melting temp.  You are going nuts with a red hot iron and all that does is locally burn the shit out of the soldermark and traces - and the result is the pic you posted.


To make this work

1) Use the right tip
2) Have your iron set to the right temp
3) Apply liberal amounts of flux so when it does melt, it flows
4) Use an iron that can maintain temp and deliver the heat into the joint
5) Make sure your tip is in good shape
6) PRE HEAT the board!!!! Use a cheap skillet from Walmart to raise the board to 150-200 degrees (F) over ambient, and voila, you just unloaded 150-200 degrees of heating work from your iron


And to put the dickhead hat on again in closing, seriously, if things start to go to shit, next time STOP and figure out what's wrong and fix it, or you'll end up with that mess again!

This is just one of several old and broken boards I had lying around so I'm using these to practice on. I'll keep all that in mind though. If it's true that this iron isn't capable of maintaining temperature well, would you recommend upgrading to one that can or will proper tip maintenance and technique suffice for now?

Also from where I work, using a skillet to heat up my boards isn't practical. Would warming it up with a heat gun have the same effect?

Nah, sounds to me like a cheap crap iron that isn't getting up to temperature, and doesn't have the heat recovery / wattage to deal with the copper heatsinking on the board. And looking at the board where he did remove parts, his too high of a temperature (when it worked) wreaked havoc.

superscott319, get a better iron. preheat the board if it has large copper fills. use the proper tip if you aren't already. don't use such high of temperature, it isn't helping you.

The brand of iron I bought seemed relatively unknown but it had decent reviews on Amazon. I took the chance and ordered it over more well known brands such as Weller and Halko because it came with a bunch of tips and other useful accessories.

Trying to learn soldering with a cheap iron may not be the best choice so what would you guys recommend if I were to get a second soldering station?
By the description given, it sounds to me like the guy's iron tip is oxidized all to hell and gone. This is blocking the heat transfer from tip to solder and is why the solder won't melt. He needs to scrape/clean the oxidation off the tip and re-tin the tip.
Nah, sounds to me like a cheap crap iron that isn't getting up to temperature, and doesn't have the heat recovery / wattage to deal with the copper heatsinking on the board. And looking at the board where he did remove parts, his too high of a temperature (when it worked) wreaked havoc.

superscott319, get a better iron. preheat the board if it has large copper fills. use the proper tip if you aren't already. don't use such high of temperature, it isn't helping you.

Obviously that was the initial problem, and for certain the board has been severely damaged by his approach. I was responding to what seemed like the only question I saw: why won't the solder melt now? And again, if it melted well enough when he originally commenced work to use a solder sucker or braid, it was obviously melting solder fine when he started, and now it won't. So what changed?  My guess by that description is a severely oxidized tip. To the O.P.: Is your iron's tip black?

My iron's tip isn't black but it's no longer shiny and solder will no longer stick to it.

Thanks for all the helpful advice everyone, I really appreciate it.
 

Offline robrenz

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Re: How to Remove Solder that Won't Melt?
« Reply #23 on: August 19, 2013, 01:46:59 PM »
I am going to get crucified for this but It has worked for me for 40 years.  Get yourself some Nokorode paste flux (Zinc Chloride) at the local hardware store. You don't use it to flux your electronic joints! Just dip your iron tip into it until the solder will wet onto the tip. Wipe the tip on your wet sponge and then solder with good rosin based flux and solder. whenever the tip starts to not wet well give it a dip in the Nokorode again.

Offline Corporate666

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Re: How to Remove Solder that Won't Melt?
« Reply #24 on: August 19, 2013, 02:10:38 PM »

This is just one of several old and broken boards I had lying around so I'm using these to practice on. I'll keep all that in mind though. If it's true that this iron isn't capable of maintaining temperature well, would you recommend upgrading to one that can or will proper tip maintenance and technique suffice for now?


I have no experience with that particular iron, so I can't say if it can maintain the heat to your board, but if you look on eBay, you can pick up a Pace (Heatwise or ST series are good) for under $100.  I have those at the shop as well as Metcals (the Metal cost something like $1,200) and I much prefer the Pace to the Metcal - it heats up faster, can deliver more heat, cheaper tips, tips last forever, etc, etc. 

Lots of folks like the Hakko units as well, but I'd say Pace is a pretty big step up from a Hakko, IMO.
It's not always the most popular person who gets the job done.
 


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