Help please. how lomg does it take to remove a bad cap?

[tommy]

Newbbie tried many times to remove bad caps, but never get one done. Used a 30W soldering iron. How long does it usually take to remove one cap? If you could post detailed procedure for caps removal, that would be greatly appreciated. Thank you.

[PCBONEZ]

Re: Help please. how lomg does it take to remove a bad cap?

Motherboards are thick and you need to heat it all the way through.
[And quickly to localize the heat to the work.]
Most people use a 40 to 60 watt iron.
Also solder wick helps. (The solder doesn't reform in the joint if it's gone.)

Practice on something that's not important.

[i4004]

Re: Help please. how lomg does it take to remove a bad cap?

it takes about 5-10sec and not all of that time is heating.
first you heat one pin, wiggle it out a bit, then 2nd one,wiggle, then go back to first one, and then 2nd one again...at that point it's usually out.
as pcbonez said, you need more power there.

get some sort of soldering station if you'll be doing it frequently.
get it if you like soldering at all.

[linuxguru]

Re: Help please. how lomg does it take to remove a bad cap?

As others have said, it helps to have a higher-powered iron for desoldering. Another trick is to add a drop of Radio Shack 63:37 Sn:Pb solder to the pad/leads that are being desoldered - it melts a few degrees lower than 60:40 or 55:45 solder that most of the low-cost consumer-electronics wave-soldered boards use, allowing easier desoldering. Before soldering in the new caps, try to remove all of the old solder bead using a wick and/or desolder pump.

[starfury1]

Re: Help please. how lomg does it take to remove a bad cap?

here is a link to Willawake's FAQ

https://www.badcaps.net/forum/showthread.php?t=485

there are other threads on it so try the search function as well.

As above a hotter iron really does help for removal

clean tip but make sure it temp gets up before trying

you may find that one side is hardener then the other with the caps
(this is apparently due to the power/ground plane setup on the MB)

also as pointed out add a smidgen (interesting point linuxguru on 63/37) of solder this will help with heat transfer
wiggle or walk the cap out (side to side motion)

you have to be some what careful cause the more heat you apply over time the more chance of causing damage ...
this is why a hotter temp iron for removal is recommended

Also dont "force" the cap, us a little but not too much you may possibly, at best damage the via at worst may rip it out
(thats the mental hole its self)

you need to be sure solder is in a liquid state.

lastly learn the hole clearing method with a STAINLESS STEEL needle (or pick)

I would practice this on junk before attacking you MB...
If you can find some old not working MB's practice on them.

Its not hard you just need to practice.

your iron may not be up to the task as the MB will act like a heat sink pulling heat away,
if your iron cant get back to temp fairly quickly you will probably have to get an other.
the last thing you want to do is damage the PCB

HTH

Cheers & Welcome to BCaps

[willawake]

Re: Help please. how lomg does it take to remove a bad cap?

trick is that first you add new solder to the existing, otherwise you get nowhere

also it is not only a matter of wattage of iron, like 30w is kinda low, 40w would be minimum, but also the tip. with my iron only the 3mm chisel is working for motherboards, all other thinner tips are not getting hot enough.

very long heating, where you are struggling to get the cap out because of the heat of the iron is likely to end up with damage to the board

[tommy]

Thank you so much for your inputs.

I really appreciate your great help. It seems that I used a soldering iron with too low watt. I heated the joint for about a minute, I could feel that the local PCB and the cap on the other side of the motherboard were hot, but the solder was never melted. Hope I have not damaged the motherboard. I will buy a high watt soldering iron and try again according to the methods your guys suggested. Thanks again.

[starfury1]

Re: Help please. how lomg does it take to remove a bad cap?

"about a minute"....way way too long 5 ~10 sec's absolute tops if you haven't got it by then your doing something wrong

Take note on Willa's tip suggestion (thanks willa)

Always "TIN the TIP" (means putting abit of solder on it) then clean with proper cleaning thing like the brass wool stuff or damp sponge or even wipe tip on the liltle house paper
ideally a dry clean is better as wet damp sponge cools tips.

it must be shiny not dark and oxide on it or you just spinning your wheels and get nowhere fast.....

As we have all said a little bit of solder will go a long way in getting the heat into the joint so it all goes liquid quick.

HTH

cheers

[Fizzycapola]

Re: Help please. how lomg does it take to remove a bad cap?

Solder should melt almost instantly.

[Leung Kai-yan]

Re: Help please. how lomg does it take to remove a bad cap?

Newbbie tried many times to remove bad caps, but never get one done. Used a 30W soldering iron. How long does it usually take to remove one cap? If you could post detailed procedure for caps removal, that would be greatly appreciated. Thank you.

Dear Friend(s),
I do the work with a 40 watts iron of the brand of the Goot. The leads of a capacitor very near the printed circuit should be touched with only the molten solder on the tip of the iron but not the tip!

[Leung Kai-yan]

Re: Help please. how lomg does it take to remove a bad cap?

trick is that first you add new solder to the existing, otherwise you get nowhere

also it is not only a matter of wattage of iron, like 30w is kinda low, 40w would be minimum, but also the tip. with my iron only the 3mm chisel is working for motherboards, all other thinner tips are not getting hot enough.

very long heating, where you are struggling to get the cap out because of the heat of the iron is likely to end up with damage to the board

Dear Sir,
I like your former picture.

[Computergeek1200]

Re: Help please. how lomg does it take to remove a bad cap?

I would also make sure you have a good tip on your iron. If you don't, you can use a grinder to reform your tip. Lead free solder needs more heat to melt. thus i recommend 60/40 Pb/Sn
ps: DON'T PUSH YOUR IRON INTO THE BOARD.

[linuxguru]

Re: Help please. how lomg does it take to remove a bad cap?

Don't even attempt to file or grind a ceramic tip, like the ones on entry-level Goots and Hakkos - the tips will be destroyed forever. These should be cleaned hot on a moist sponge only.

[Fizzycapola]

Re: Help please. how lomg does it take to remove a bad cap?

With a 60watt iron. (any will do be it $1 or $700,000,000,000)

You will not have trouble removing capacitors, using gravity or similar force but not much greater that normal gravity and melting the solder they will simply fall out.

After using your iron. Dip it in solder, wipe it clean but still tinned on a pristine area of sponge. Let it cool down as slowly as possible to minimise shock. Once it's cooled it may have a used look to it. You can restore it to brand new looking condition with some jewellers polish blocks ( I use grey - stainless steel) and a felt or better buffing wheel attached to a dremel (although $5 minitool is just as good if not better for the lower torque.)

I have a range of irons, all the cheapest you can get, because I like to break even and always justify my expenses, really spending money isn't something I enjoy, for example people spend thousands to overclock cheap CPU's when they could just buy a good CPU in the first place keep their mouths shut and stop posting on forums for other people like them to wank over the brushed interiors of their PC cases.

20W - Surface mount components, MLCC's (tinned tip to part), Small cap (normal soldering)
25W - I don't know why I have this.
30W - I don't know why I have this. I did use it once to replace a MLCC that fell off something though and it seemed to stick.
2 x 60W - Big cap work 8mm+

One of my main enemies is my caffeine fuelled anxiousness and nervousness when soldering something of great importance to me. I play back the whole soldering process in my mind as if I've done it before starting. Though I can't stop my hand from shaking erratically and sporadically, I have removed lots of MLCC's this way in one nervous shake of my 60W and ground through boards when attempting quick clean ups using power tools in amazingly cramped hostile environments. But thats my problem I hope you don't suffer this.

[jpdoe]

Re: Help please. how lomg does it take to remove a bad cap?

Hi, Fizzicapola. I'm new to soldering, and I'm trying to learn how to gauge which soldering iron wattage is appropiate for each job. I bought a 60w soldering iron, and I find it quite strong for some of the soldering jobs I attempted, mostly with PSUs. I'm still learning how to use it. I got used to heat the components for ages with a 30w iron, so I found out I must move much faster with the 60w one. So my question is: is it OK to use the 60w iron for every soldering / desoldering job involving ATX PSUs? Or I have to evaluate the ammount of heat the specific area I'm gonna work on is gonna dissipate?

[jpdoe]

Re: Help please. how lomg does it take to remove a bad cap?

Also, I would appreciate if someone would explain the meaning of the image Fizzicapola posted regarding the correct / incorrect way to position the tip of the soldering iron. It would seem this picture indicates that the tip shoudn't contact the capacitor leg, but only the copper on the PCB. That would contradict most soldering guides I saw, since they say that the iron tip should contact both objects going to be soldered, so that both are hot when applying the solder to them. Otherwise, you get a dry joint.

PS: Oh... Disregard this post. I only now realize the blue line in this image isn't the capacitor leg, but the solder being applied.

[i4004]

Re: Help please. how lomg does it take to remove a bad cap?

use 60w only when you see 30w can't do it.
for psu i would think 60w would only be needed to remove heatsinks and so...

i think 60w is non-elegant.
how many seconds does it take for it to burn a bit of solder and become black and crusty again?
3?4?

if you need more power than 30w can provide you should probably get a soldering station. crank it up when you need it, otherwise keep it lower...

[PCBONEZ]

Re: Help please. how lomg does it take to remove a bad cap?

I like to use a 60 watt to remove caps and a 40 watt to put them back after the PCB is cleaned up. [No rules, it's just what works best for you.]

30 watt is okay for light duty stuff but not hot enough for thick PCBs.

Contact should be *mostly on pad but also touching lead.
PCB must be heated for solder to flow through the hole and bond properly to PCB.

.

[jpdoe]

Re: Help please. how lomg does it take to remove a bad cap?

@i4004: the solder turns grey quite fast, but nevertheless the iron gets so hot it doesn't seem to matter much when I'm desoldering. The technique I've been trying when soldering is to clean the tip when I've had the iron unused for a couple of minutes. I'm tempted by the soldering stations I see online, but I want to learn the basics before committing to one.

@pcbonez: I own two irons, 30w and 60w respectively, both with ceramic tips. I've have been looking for a 40w one, but I thoght it woudn't be much different than my 30w. So I bought one too cheap, and comparing its components I decided it must be really a 30w one. In consequence, I have to shop around for another 40w iron. I won't cry too much... I only spent usd1.50 I wanted to try anyway because down here the only good brand of irons are Taiyo and Goot, but I can find same quality chinese ones for half the price. I just was feeling extremely cheap that day.

[jpdoe]

Re: Help please. how lomg does it take to remove a bad cap?

I tried to edit the last post so I wouldn't thread hijack so much, but got nailed with the 10min edit limit. I hope you don't mind.

What makes things harder is that locally I can only find regular conical tips. Not one chisel tip on sight. Another thing is the matter of replacement parts. I only found two brands for which I can find tip replacements: Taiyo/Goot and an argentinian importer's brand. The argentinian one is non ceramic. The Taiyo/goot are ceramic, but the replacement tip cost as much as a new good quality 40w chinese iron. So I'm beginning to think this is just a scam by the Taiyo importers and dealers.

How do you think ceramic and non ceramic tips compare?