One simple question

[Shodan486]

I just have one, maybe stupid, question:

When recapping the board, are we damaging the board by soldering? I mean how many times can you recap a board in its lifetime? Are we not somehow lowering the endurance of the soldering points when replacing some parts on a mobo? I'm especially talking about the thru-hole technique.

[shadow]

Re: One simple question

I think it has got more to do with the skill of the person soldering.

However it is true that excessive heat can damage components on the board. This is why we try to keep the time that the iron is on the board to a minimum. This is why a moderately high wattage iron is recommended when soldering boards.

The real risk with soldering stuff is what you as the solderer does. What if your finger slips and u damage the board physically with your soldering iron or some other piece of equipment. Another thing to watch out for is to ensure that the solder has melted before removing components. Nothing worse that ripped vias or ripped tracks or pads.

Either way, I do not think there is any reason to solder something in a particular location more than a few times, so I would say there is nothing to worry about.

Others on this forum will have more detailed knowledge on this topic.

[Shodan486]

Re: One simple question

I must agree, I always thought that soldering the same place, thus worsening the points, can be done only by clumsy hands or bad material used for this... I thought that the PCB could crack or burn on the particular place, hope I am still right...And also welcome for some other thoughts...

[Topcat]

Re: One simple question

If you use good components, properly cool the system, and know how to solder in a competent manner, you should never have to recap a board more than once in its useful lifetime.

[Shodan486]

Re: One simple question

Yes, I do understand...BUT my point is -> Let's put it this way - I am a grandmaster in soldering, I have the best equipment in the whole galaxy, I can cool the place absolutely perfectly - how many times can I solder something at the same particular place? Dont speak about the moral usefulness of the board and so, I just want pure theory/field experience. For example can I solder at the same place 10 times? Dont ask questions like '' why would you '' or '' there is no need ''...just answer YES / NO and why...the point is that I love a certain motherboard and I know that some parts ''die'' within a certain time, so I have to recap or re-whateverelse - Just want the board work for the next 60 years

[kc8adu]

Re: One simple question

depends on the quality of the board.

[370forlife]

Re: One simple question

depends on the quality of the board.

Yes. I finally recapped my VP6 with my hakko and even at 599C I could probably held it on the pcb for a few seconds without burning it.

The only board that I could burn the PCB was a cheap BCC 550W psu based off a old design CWT 235W.

[Topcat]

Re: One simple question

Yes, I do understand...BUT my point is -> Let's put it this way - I am a grandmaster in soldering, I have the best equipment in the whole galaxy, I can cool the place absolutely perfectly - how many times can I solder something at the same particular place? Dont speak about the moral usefulness of the board and so, I just want pure theory/field experience. For example can I solder at the same place 10 times? Dont ask questions like '' why would you '' or '' there is no need ''...just answer YES / NO and why...the point is that I love a certain motherboard and I know that some parts ''die'' within a certain time, so I have to recap or re-whateverelse - Just want the board work for the next 60 years

umm....ok....

You're asking a question that's impossible to answer. Recap your board every day until it falls apart, and then let us know how many times you recapped it before the through holes were destroyed. How's that?!

[370forlife]

Re: One simple question

I would say 10 or 12 times before something goes wrong.

[Shodan486]

Re: One simple question

umm....ok....

You're asking a question that's impossible to answer. Recap your board every day until it falls apart, and then let us know how many times you recapped it before the through holes were destroyed. How's that?!

I gotta say it's not a bad ideda . No I mean it, I'll try as soon as I get my '' Perfect tools of Galaxy''. What would you guys recommend, what brand and characteristics? Of course I am lame and new to soldering practice, need more experience...

[Shodan486]

Re: One simple question

I would say 10 or 12 times before something goes wrong.

Does this count for the ''chip'' capacitors soldered on the mobo using Surface Mount technology? I mean they need to be soldered on those metal pads, so I expect it cannot be damaged since nothing is done to the interior of the PCB.

[linuxguru]

Re: One simple question

The number of times you can recap a particular cap on a mobo depends on a lot of things, apart from the skill and equipment you use.

1) Is it standard 60:40 tin-lead solder or some RoHS crap? If it's high-melting point RoHS solder, you may not even be able to recap it once. You may be able to recap standard 60:40 joints maybe half-a-dozen times. If you have gallium-based desoldering material you may be able to remove solder from a solder joint an indefinite number of times - maybe 100 times or more..

2) How much metal area is there on the pad? The greater the metal area, the lower the risk of delamination. However, if it's a large power/ground plane, it will also conduct heat away quickly, making it harder to desolder. There's an optimal tradeoff somewhere in between.

3) What other components are nearby? If the cap is in a cluttered area, the risk of damaging another component is higher. If there are SMTs nearby, especially on the same power plane as the cap, they may get dislodged while desoldering the cap. If the cap is located between other caps and MOSFET heatsinks, it may be very difficult to remove it without removing some other parts.

4) What traces run in the vicinity of the pads? If there are fine signal traces adjacent to the pad, there's a risk of damaging them while desoldering the cap.

In general, it's far harder to desolder and clear the through-holes, than it is to solder a new cap. Most of the risk is associated with the desoldering and hole-clearing operations.

[bw1]

Re: One simple question

Can I bring this thread back from the dead? I've run into this before, and man, does it %&#$ me off:

The number of times you can recap a particular cap on a mobo depends on a lot of things, apart from the skill and equipment you use.

1) Is it standard 60:40 tin-lead solder or some RoHS crap? If it's high-melting point RoHS solder, you may not even be able to recap it once. You may be able to recap standard 60:40 joints maybe half-a-dozen times. If you have gallium-based desoldering material you may be able to remove solder from a solder joint an indefinite number of times - maybe 100 times or more..

What is the correct process to proceed here? Most recently was a video card. Nothing special, but for the couple bucks it would cost to re-cap, it would be worth it for a decent dual-VGA card.

THE SOLDER WON'T MELT FOR CRAP. With direct heat from a 50w temp-controlled station maxed out, directly on the back of the board and using some solder to help transfer heat, the stupid thing won't budge a millimeter. Any longer and I'd definitely risk heat damage, if I didn't already.

In this case, probably not worth the effort. It's not a special video card. But I've run into this in the past, before having this forum and people to ask.

Please advise!

[MXM]

Re: One simple question

if u cant get a non temp controlled iron (might help) try to get some flux and add to it, and also theres this complement for desoldering, i think is made specially for SMDs desoldering, it kinda gets the soldering out by sticking to it and sometimes makes it easier to desoldered, or even remove and then clean/desolder-more...

i'd also try heating the board and see what happens.... help with some sort of metal thin stick or such...

note that this isnt a proven procedure... is part of what i do when i go thru what you described.

jm2c

peace.

[Per Hansson]

Re: One simple question

What kind of tip do you have on your soldering iron?
A smaller tip will get colder quicker when you touch the cold PCB
A bigger tip will store more heat inside it, so it is easier to desolder with a bigger tip usually...

[stj]

Re: One simple question

50w wont do it.

[bw1]

Re: One simple question

I know exactly what you mean about not enough power, but I didn't really care about this particular card so I kept on heating it and believe me, there should have been enough heat there.

AFAIK, the extra power helps get the heat there faster so it doesn't have to be hot so long. Not caring about heat there too long.... well, I've never encountered solder so stubborn.

[retiredcaps]

Re: One simple question

well, I've never encountered solder so stubborn.

This works for me. YMMV. I add a bit of solder, just enough to cover the joint, and then remove it using my desolder pump.

My soldering iron is an ebay "sort by lowest price" 40W.

[bw1]

Re: One simple question

Yeah usually I've got a desolder pump that works very well. I have a feeling this is some sort of ROHS high-temp solder crap.

[retiredcaps]

Re: One simple question

I have a feeling this is some sort of ROHS high-temp solder crap.

I should have been more specific. I add a bit of 60/40 solder first then use the desolder pump. This works on RoHS boards as well for me.