Also, if the solder is unleaded, apply some fresh leaded solder, it will mix and make the other easier to melt

Matth79 wrote on 2025-05-25, 21:51:

Also, if the solder is unleaded, apply some fresh leaded solder, it will mix and make the other easier to melt

Yep, i think the board used lead free solder and I'm adding 60 40 leaded solder to the joints every time before using the gun. Otherwise it's super difficult to get anything to melt.

randomdavid wrote on 2025-05-25, 18:38:

What am I doing wrong? Should I try to preheat with a hair dryer? Do you guys have any advice for me?

I heard that the VRM low caps are supposed to be even more stubborn, so I will need all the advice I can get!

Don't be discouraged, those boards from around 2005 onwards are very difficult to work on, you're basically dealing with 3 problems at once:

• Awful lead-free solder that takes longer to melt
• Large ground and power planes that sink all the heat away
• Teeny-tiny holes and very thin pads lead to a reduced contact area with your iron/desoldering gun, making heat transfer even more difficult

In addition to what has already been mentioned (mix some leaded solder into the joints, preheating and so on) let me suggest a couple of additional things.

One is to get a kit of those hollow de-soldering needles that are easily found on eBay. Place the needle on the hole you need to clear, add some heat with your iron and once the solder is melted push the needle to clear the hole. It's not 100% effective but it's helpful in many cases.

The other suggestion is a technique that I find very useful if you have a de-soldering gun, so it may also work for you: first of all, don't de-solder the component right away, just add a good amount of leaded solder to the joints and make sure it mixes well with the old lead free crap. Then, place the board in vertical position, and with one hand hold the capacitor/component you're trying to remove, while the other hand is for the gun. Now, try to wiggle the component as you heat the joint, at some point you should feel it moving freely once the solder has melted on both sides, so that is your cue to press the trigger and suck the solder out.

I see you have already noticed that in most cases one of the holes is much easier to de-solder than the other (which is on a large ground/power plane). With the technique described above, it's easier if you start with the "easy" hole and then with the difficult one you can apply heat and feel when the component is moving freely.

Finally, don't worry about that damage, it's just the solder mask that was over the large copper plane as you can see, if you're worried about it you can always get some UV curable solder mask and apply it after replacing the cap, but it's not strictly necessary. However, be careful when working on a hole that has thin traces nearby as they can be easily obliterated by the heat and sucking action (ask me how I know about that 😒).

randomdavid wrote on 2025-05-25, 20:42:

Do you think I can use a hair dryer for this? This doesn't feel like it would require the precision of a proper hot air station, so maybe I can get away with a hair dryer and a narrow nozzle?
Plus a hot air station would be another £60-80...

If you have a very powerful hair dryer it might help, but you would need temperatures above 150 - 200C in that area to make a real difference (and I have a hard time believing that you can achieve that with an average dryer). Doesn't hurt to try, though. 😀

Thanks to everyone who replied, I now have some good tips and renewed vigor. After giving it some more thought, I think it's best to wait a bit before pressing forward. I ran out of space for more gear, and need some time to make sure the board is stable. Although I bought polymer replacements for the VRM low caps, the stock ones are Panasonic FL series which are supposed to be good, so I'm not in a terrible hurry to replace them.

TheMobRules wrote on 2025-05-26, 04:53:

Don't be discouraged, those boards from around 2005 onwards are very difficult to work on, you're basically dealing with 3 probl […]
Show full quote

Don't be discouraged, those boards from around 2005 onwards are very difficult to work on, you're basically dealing with 3 problems at once:

• Awful lead-free solder that takes longer to melt
• Large ground and power planes that sink all the heat away
• Teeny-tiny holes and very thin pads lead to a reduced contact area with your iron/desoldering gun, making heat transfer even more difficult

Wow, your comment is awesome! I think you nailed all of my problems. I have asked myself why I was having so much difficulty, while Youtube videos make it look so easy. Now I know most of them were filmed using leaded solder and giant through holes. It wouldn't make a good desoldering gun video if it didn't look easy on camera I guess.

TheMobRules wrote on 2025-05-26, 04:53:

One is to get a kit of those hollow de-soldering needles that are easily found on eBay. Place the needle on the hole you need to clear, add some heat with your iron and once the solder is melted push the needle to clear the hole. It's not 100% effective but it's helpful in many cases.

Interesting, I wonder what is the benefit of the needle being hollow?
The Proskit station came with some cleaning rods of 3 sizes. I did try using that but it didn't quite work out, the solder in the hole couldn't melt so the rod would not push through.

TheMobRules wrote on 2025-05-26, 04:53:

The other suggestion is a technique that I find very useful if you have a de-soldering gun, so it may also work for you: first of all, don't de-solder the component right away, just add a good amount of leaded solder to the joints and make sure it mixes well with the old lead free crap. Then, place the board in vertical position, and with one hand hold the capacitor/component you're trying to remove, while the other hand is for the gun. Now, try to wiggle the component as you heat the joint, at some point you should feel it moving freely once the solder has melted on both sides, so that is your cue to press the trigger and suck the solder out.

This tip made me realise that since I was able to pull the cap out, that means all the solder must have melted at that point.
The problem was that the hole is tiny, so it's hard to tell if the leg is free, without pulling it out. I also had to trim the leg to almost flush with the board, so I can add more solder to it, and as a result, the cap pulls out way too quickly for me to react. It's a skill issue I think. Maybe I should try to melt all the solder without trimming the leg.

TheMobRules wrote on 2025-05-26, 04:53:

Finally, don't worry about that damage, it's just the solder mask that was over the large copper plane as you can see, if you're worried about it you can always get some UV curable solder mask and apply it after replacing the cap, but it's not strictly necessary. However, be careful when working on a hole that has thin traces nearby as they can be easily obliterated by the heat and sucking action (ask me how I know about that 😒).

Few! That's a relief. I think I'll leave it like that so it's easier to get that cap out in the future if needed! Lucky I didn't burn it to a point that the 2 legs would short!

By the way, does anyone know what these tiny holes are for? There are 2 - 3 of them next to the difficult holes, and for some, I ended up either sucking them dry or bridging them with the cap leg hole.

randomdavid wrote on 2025-05-25, 18:38:

Now, the bad news, and I seriously need help on this one: […]
Show full quote

Now, the bad news, and I seriously need help on this one:

Even with the desoldering gun, it was still a struggle! Especially for the ground holes (i think they are ground holes, they are the holes with 2 or 3 smaller holes surrounding them)

Today for nearly 4 hours, I did this on repeat:

Add flux, add 60-40 leaded solder, use gun, see that the hole is still not clear.

I started at 350C and went all the way to 450C, no dice. Held the gun at the hole, 90 degrees angle, for 10 seconds all the way to a minute, no dice.
Because of this, I damaged the board a little! A friend told me the lacquer is burned?
Thankfully the board still works!

What ended up working was to first remove the cap by heating the joint, then sandwich the hole between the soldering iron at 390 C and the gun at 450 C for 10 seconds, then suck. I feel that this is way too extreme and there should be a better way.

Note that the gun works fine, because the other non-ground hole was super easy, just add flux, new solder, suck, and it's all out.

The attachment IMG_20250525_153801.jpg is no longer available

What am I doing wrong? Should I try to preheat with a hair dryer? Do you guys have any advice for me?

I heard that the VRM low caps are supposed to be even more stubborn, so I will need all the advice I can get!

What you're describing here is exactly the reason I *NEVER* bought a desodering gun (after trying out a really good Hakko one at a repair shop I was working at the time).

Large copper planes on the CPU VRM low (they are actually the CPU V_core planes and not grounds) will always be tough to clear with *any* type of desoldering equipment - be it braid, desodering gun, or manual solder sucker / vacuum pump. I've tried all of these many many times and never found any of them to work well or reliably on the CPU VRM low side of motherboards, especially ones that used early lead-free solder (very tin-heavy and high melting temperature.)

So to answer you more directly - no, you're NOT doing anything wrong with your equipment.

That said, I have a much easier method of removing caps and clearing holes on motherboards.

For removing caps, I use the "walk out" method, as seen here (scroll down to post #23 on that page, as post-linking doesn't seem to work on BCN anymore):
https://www.badcaps.net/forum/general-topics/ … t=23#post218039

After removing the cap(s), I then use a stainless steel needle and my iron to clear the holes. Basically, I heat the hole I want to clear from solder and push the solder out from the other side (the component side) with the SS needle. To make sure the hole stays clear, I them remove my soldering iron and give the solder a second or two for it to cool down while the needle is still inserted in the hole. Then finally I pull the needle out. If the needle appears "stuck" rock its top in slight circling motion and then try pulling it out. If it's a true stainless-steel needle and not just a cheapo coated one, then solder will NOT stick to it.

The above is how I do all of my motherboard and I can de-cap and clean a board about as fast as one would with a desoldering gun... except, I just won't struggle when I get to the CPU VRM low side, which is where the desoldering gun becomes no good.

TheMobRules wrote on 2025-05-26, 04:53:

The other suggestion is a technique that I find very useful if you have a de-soldering gun, so it may also work for you: first of all, don't de-solder the component right away, just add a good amount of leaded solder to the joints and make sure it mixes well with the old lead free crap. Then, place the board in vertical position, and with one hand hold the capacitor/component you're trying to remove, while the other hand is for the gun. Now, try to wiggle the component as you heat the joint, at some point you should feel it moving freely once the solder has melted on both sides, so that is your cue to press the trigger and suck the solder out.

Excellent tip!
This is something I actually do as well, except I just do it with my soldering iron rather than a desoldering gun when desoldering the caps.
But it's the same thing - I add flux and fresh solder onto each joint of each cap I want to remove and just ever so slightly "wiggle" the cap as I do that. Then I go ahead and use my "walking out" method to remove the cap. But indeed this does make removing caps (and other components) much easier.

randomdavid wrote on 2025-05-26, 20:19:

By the way, does anyone know what these tiny holes are for? There are 2 - 3 of them next to the difficult holes, and for some, I ended up either sucking them dry or bridging them with the cap leg hole.

Those are called vias. They are basically tiny through-holes with plating on their walls to connect different layers of the board together. You find them right around the holes of each cap so that any interconnecting layers are well-connected to that layer you see on the bottom of the board. After all, the CPU VRM low side can be supplying upwards of 50 Amps of current... so that's why there are so many of them. If there were only a few used, they would become high-resistance points and either burn out or cause lots of voltage drop, which is not desirable in a low-voltage circuit such as the CPU V_core rail.

momaka wrote on 2025-05-26, 21:14:

What you're describing here is exactly the reason I *NEVER* bought a desodering gun (after trying out a really good Hakko one at […]
Show full quote

randomdavid wrote on 2025-05-25, 18:38:

Now, the bad news, and I seriously need help on this one: […]
Show full quote

Now, the bad news, and I seriously need help on this one:

Even with the desoldering gun, it was still a struggle! Especially for the ground holes (i think they are ground holes, they are the holes with 2 or 3 smaller holes surrounding them)

Today for nearly 4 hours, I did this on repeat:

Add flux, add 60-40 leaded solder, use gun, see that the hole is still not clear.

I started at 350C and went all the way to 450C, no dice. Held the gun at the hole, 90 degrees angle, for 10 seconds all the way to a minute, no dice.
Because of this, I damaged the board a little! A friend told me the lacquer is burned?
Thankfully the board still works!

What ended up working was to first remove the cap by heating the joint, then sandwich the hole between the soldering iron at 390 C and the gun at 450 C for 10 seconds, then suck. I feel that this is way too extreme and there should be a better way.

Note that the gun works fine, because the other non-ground hole was super easy, just add flux, new solder, suck, and it's all out.

The attachment IMG_20250525_153801.jpg is no longer available

What am I doing wrong? Should I try to preheat with a hair dryer? Do you guys have any advice for me?

I heard that the VRM low caps are supposed to be even more stubborn, so I will need all the advice I can get!

What you're describing here is exactly the reason I *NEVER* bought a desodering gun (after trying out a really good Hakko one at a repair shop I was working at the time).

Large copper planes on the CPU VRM low (they are actually the CPU V_core planes and not grounds) will always be tough to clear with *any* type of desoldering equipment - be it braid, desodering gun, or manual solder sucker / vacuum pump. I've tried all of these many many times and never found any of them to work well or reliably on the CPU VRM low side of motherboards, especially ones that used early lead-free solder (very tin-heavy and high melting temperature.)

So to answer you more directly - no, you're NOT doing anything wrong with your equipment.

That said, I have a much easier method of removing caps and clearing holes on motherboards.

For removing caps, I use the "walk out" method, as seen here (scroll down to post #23 on that page, as post-linking doesn't seem to work on BCN anymore):
https://www.badcaps.net/forum/general-topics/ … t=23#post218039

After removing the cap(s), I then use a stainless steel needle and my iron to clear the holes. Basically, I heat the hole I want to clear from solder and push the solder out from the other side (the component side) with the SS needle. To make sure the hole stays clear, I them remove my soldering iron and give the solder a second or two for it to cool down while the needle is still inserted in the hole. Then finally I pull the needle out. If the needle appears "stuck" rock its top in slight circling motion and then try pulling it out. If it's a true stainless-steel needle and not just a cheapo coated one, then solder will NOT stick to it.

The above is how I do all of my motherboard and I can de-cap and clean a board about as fast as one would with a desoldering gun... except, I just won't struggle when I get to the CPU VRM low side, which is where the desoldering gun becomes no good.

TheMobRules wrote on 2025-05-26, 04:53:

The other suggestion is a technique that I find very useful if you have a de-soldering gun, so it may also work for you: first of all, don't de-solder the component right away, just add a good amount of leaded solder to the joints and make sure it mixes well with the old lead free crap. Then, place the board in vertical position, and with one hand hold the capacitor/component you're trying to remove, while the other hand is for the gun. Now, try to wiggle the component as you heat the joint, at some point you should feel it moving freely once the solder has melted on both sides, so that is your cue to press the trigger and suck the solder out.

Excellent tip!
This is something I actually do as well, except I just do it with my soldering iron rather than a desoldering gun when desoldering the caps.
But it's the same thing - I add flux and fresh solder onto each joint of each cap I want to remove and just ever so slightly "wiggle" the cap as I do that. Then I go ahead and use my "walking out" method to remove the cap. But indeed this does make removing caps (and other components) much easier.

randomdavid wrote on 2025-05-26, 20:19:

By the way, does anyone know what these tiny holes are for? There are 2 - 3 of them next to the difficult holes, and for some, I ended up either sucking them dry or bridging them with the cap leg hole.

Those are called vias. They are basically tiny through-holes with plating on their walls to connect different layers of the board together. You find them right around the holes of each cap so that any interconnecting layers are well-connected to that layer you see on the bottom of the board. After all, the CPU VRM low side can be supplying upwards of 50 Amps of current... so that's why there are so many of them. If there were only a few used, they would become high-resistance points and either burn out or cause lots of voltage drop, which is not desirable in a low-voltage circuit such as the CPU V_core rail.

Wow, thank you so much for such a detailed response!
I will definitely try the walk out method and the needle method! That sounds like it might even work without using just a braid to clean up afterwards. The key then is to heat the hole up the a point where solder on the other side would melt. I had a lot of trouble with this, so much that i needed to use both the gun and the iron on 2 sides!

Regarding the vias, I guess I should try to fill all the emptied holes.

Is it OK that I bridged some of them with the capacitor leg? If it's just to make connections to the vrm layer, which the capacitor is already connected to, i feel like it should be fine?

randomdavid wrote on 2025-05-26, 21:31:

Regarding the vias, I guess I should try to fill all the emptied holes.

No need.
Their walls are made of etched copper, so even with no solder, they are still connected perfectly fine.

randomdavid wrote on 2025-05-26, 21:31:

Is it OK that I bridged some of them with the capacitor leg? If it's just to make connections to the vrm layer, which the capacitor is already connected to, i feel like it should be fine?

Yup, all fine. All of those vias, the capacitor lead, and the piece of copper plane are electrically connected.... so bridging anything with more solder doesn't really change anything or harm anything. If anything, it makes the connection even tougher to burn out (not that this would ever happen.)

For caps I usually add solder to both leads and try to stretch the tip across both. I usually manage to get them out 99% of the time, and an added bonus is the leads come straight, not bent from wiggling.

My slight chinesium iron (not really sure if it's chinese, it seems too quality to be... and the packaging was mostly in EU languages with no traces of chinese. Also it's ceramic based instead of mica.) is thermally controlled up to 480*C however, and I use it at that temperature.