How to exchange caps

[trodas]

A little photo guide about how I do it :)

You will need a classic transformer soldering iron, no less that 75W. I use this oldie one for 26 years:
http://img501.imageshack.us/img501/2391/mysolderingiron1ec5.th.jpg (http://img501.imageshack.us/my.php?image=mysolderingiron1ec5.jpg) http://img242.imageshack.us/img242/3687/mysolderingiron2ay0.th.jpg (http://img242.imageshack.us/my.php?image=mysolderingiron2ay0.jpg)

Some resin is need too:
http://img294.imageshack.us/img294/306/resinat4.th.jpg (http://img294.imageshack.us/my.php?image=resinat4.jpg)

And a little bit of tin:
http://img505.imageshack.us/img505/104/tindb4.th.jpg (http://img505.imageshack.us/my.php?image=tindb4.jpg)

And tin suction tool:
http://img214.imageshack.us/img214/8917/tinsuckingtoolxd0.th.jpg (http://img214.imageshack.us/my.php?image=tinsuckingtoolxd0.jpg)

...and of course replacement caps and something with bad caps. In this case I choose very simple recap of Jaton GF2MX400 card. Of course this card is phased out and you will probably not made and 3DMark world record with it, recapped or not, but for testing or normal office use it is perfect. Thanks to it's passive heatsink and small size it is preferred graphic card, where you need just one to be. I use these cards in folding and testing machines ;)

So, let's first take a look at the card itself:
http://img490.imageshack.us/img490/7519/recapguide1rc8.jpg
As you can see, we gonna need:
1x 1000uF 6.3V d8 Samxon GC
4x 470uF 6.3V d6.3 Samxon GD
3x 10uF 25V d4 Samxon ZS

Let's take a look at the original caps...
http://img267.imageshack.us/img267/1233/recapguide2kd2.jpg
...well, it is obvious they gotta go. Asiacon is the same as Evercon and this is the same cr*p as G-Luxon... :beat:

Step first - desolder with the soldering iron the caps:
http://img267.imageshack.us/img267/2408/recapguide3ml3.jpg
Every time before use the soldering iron, dip it to the resin to protect against oxidation not only the contacts, but the actual soldering iron how wire tip. Result did not look ver pretty, but caps are gone now :D The white or shaded (or other way highlighted) holes are typically for the negative cap polarity wires. Of course you gotta stay alert for exceptions and crazy designs, witch can swap the polarity! Sometimes it is better first take a picture of the card to have proof on how it looked before... ;)

Now come the hardest step - suck off tin from at least one of the holes. Choose the one that is isolated from the rest of the PCB. This way you heat up most only small piece of tin and PCB and hence you should be able to suck the tin off easily.
http://img267.imageshack.us/img267/949/recapguide4bq6.jpg
Result - one hole is free.

Now take the replacement cap - take care about the polarization (on some cards, such as Gigabyte FX5200/FX5600XT, it is contrariwise!). Caps has one longer leg, that is the positive wire. If you have free the positive hole, you are good to go. Insert the longer positive wire inside and the negative adjust to be pressing exactly against the tin in the not free yet hole. Apply only light pressure. If you need more pressure, shorten the wires, but leave the positive wire longer.
http://img211.imageshack.us/img211/7718/recapguide5fd8.jpg

From the bottom side heat up the tin in the negative hole and after a while (depends how big area of PCB you heating up) the cap nicely slide in place. Looks this way:
http://img454.imageshack.us/img454/7913/recapguide6ze6.jpg
If you got free the negative hole instead, then cut the positive wire of the cap in middle, so it get shorter that the negative wire and then work it out same way.
Caps wires should be put thru to the end. Exception from this is only when you solder smaller or bigger spaced cap into holes that did not match. In that case - depends on how much the wires are getting dilate or closer - leave at least 3mm for the bend. Pressing too much in this case is very likely to damage almost any cap!

When you have the cap in place as it should be, then cut off the remaining wires. Leave just about 1mm from them. And then with plenty of resin again solder them.
http://img211.imageshack.us/img211/1271/recapguide7qg4.jpg
Now it does not look pretty at all, right? :redface: Well, let's continue till we have every caps soldered first.

Now will come the technical spirit in action. Using brush add the spirit in place where the resin is:
http://img211.imageshack.us/img211/9206/recapguide8gv0.jpg
And leave couple of seconds to take effect. You can see that the resin is breaking up and melting already. You can help big chunks get off by sharpened piece of hard wood - notably increasing the rate how the resin leave the PCB.

Then first with rubber, also wetted in spirit, rub off the remains of it. Last small remaining of the resin is best to get off by brush, wetted in spirit again. The brush has to have reasonably tough strings.
http://img126.imageshack.us/img126/854/recapguide9ge4.jpg
(image also show desoldered CE filters and coils replaced by pieces of wires)

With careful clean up you can get professional looking soldering joints.
http://img259.imageshack.us/img259/1065/recapguide10dl5.jpg

And now you can only be delighted looking at how the new nice caps beautifully looking at the card.
http://img211.imageshack.us/img211/8459/recapguide11my0.jpg

Whole look on the card with now exchanged caps.
http://img126.imageshack.us/img126/3314/recapguide12hl2.jpg

With such simple graphic card with minimum caps you can be done in like 10 minutes top. And with a little work you got the assurance it will not fail you for years and years. And now back with it to the computer ;)



PS. sometimes happens - especially with small caps, where one can heat up with big soldering wire tip both holes - that it is possible solder the cap w/o actually sucking off the tin. Sometimes this is also the only one possibility, when the tin did not want get off and you did not want to damage the PCB... In this case simply cut the legs to be same and much shorter (so you can apply more pressure), align them right to booth holes, hold and from the bottom start heating and push... ;)

[NINaudio]

Nice write up Trodas, and very clean work too!

[harleybro]

Very impressive work and guide trodas :thumbs::yup:

[joeMan]

Very nice :beer:

[Snafu]

Nice write up Trodas, and very clean work too!
Ditto. Good job :thumbs:

[trodas]

Thank you all, guys. I just hope this helps someone out ;)
Usually people screwing up mainboards/gfx cards and other hardware (you name it) using too underpowered soldering irons, insisting on the not transformator ones and so on, so on. I use this old transformator one to solder on every board I ever had - and guess what ;) No troubles :wpleased:

The hardest part is sucking at least one clean hole for the cap. And learning from others, I actually trying the dental toothpick now instead of sucking the tin off. Looks interesting, perhaps even notably easier - however it is a very sharp suxxka :p

One wrong move and your finger might get pierced... Definitively not a toy for childrens. Even my dentist claim I should not use it - at least not for teeths - because she insist it require some skill ;)
Maybe she is just jealous :chit:

[trodas]

Trick with dental pick ;)

The hardest part on recapping is cleaning the holes for new caps. So, there come a little trick...

http://i232.photobucket.com/albums/ee193/trodas_cr/dental_pick_trick_1.jpg

Yep, with this is the very same dental pick your dentist use to push on your teeths. You can buy it in medical supply shops, the only slight disadvantage is that the quality ones cost premium. But the vacuum tin sucking toy is not even recommended on BadCaps, because from heated PCB it easily can suck-off small traces, or by the back impact it tear them on the mobo. Sometimes it happen for me and certain low-quality mainboards (like JetWay V266B, Abit BX133 and so on) are very prone to this.

So, at first we have holes after desoldered cap (or never soldered cap there) full of tin:

http://i232.photobucket.com/albums/ee193/trodas_cr/dental_pick_trick_2.jpg


So just attach the pick and reasonably push on it with one hand to stay in place (beware, it is very sharp, be carefull!):

http://i232.photobucket.com/albums/ee193/trodas_cr/dental_pick_trick_3.jpg


From the other side heat up the PCB with iron and soon the pick do thru the hole like hot knife thru butter and try to push it as far, as you manage with reasonably small force:

http://i232.photobucket.com/albums/ee193/trodas_cr/dental_pick_trick_4.jpg


Immidetelly after you reach the end, start wriggling with it to sides/up and down a bit, so it will not stuck to the tin or resin in the hole:

http://i232.photobucket.com/albums/ee193/trodas_cr/dental_pick_trick_5.jpg


Now the big metal chunk of this dental pick come to play - it disperse the heat perfectly, so in just a few seconds we have a free hole:

http://i232.photobucket.com/albums/ee193/trodas_cr/dental_pick_trick_6.jpg


Now let's repear that with the second hole, when we want to solder the cap inside easily (or he is on wrong place with bad access):

http://i232.photobucket.com/albums/ee193/trodas_cr/dental_pick_trick_7.jpg


Push a little and we are on the second side easily again:

http://i232.photobucket.com/albums/ee193/trodas_cr/dental_pick_trick_8.jpg


...and now we have both holes free and perfect for soldering new cap in:

http://i232.photobucket.com/albums/ee193/trodas_cr/dental_pick_trick_9.jpg


As you can clearly see, this methos is easy, comfortable and fast. And the dental pick clean really well. Tin does not get attached on it at all and resin only very lightly. Cleaning with piece of old clothing and technical spirit is done in few seconds. The steel is very high quality, elastic a little and very hard to break. Almost impossible, I never managed it yet and I tried :) Comparing that to the nevereding cleaning of the vacuum tin suction tool... well, this is not comparable at all. Productivity in recapping go very much up using dental pick. Caps almost like jumping in the board ;) :D

Sometimes it happens that in the holes remain too much tin, that create knob around the holes, where capacitor will be soldered. Such knobs that are on the top of the PCB are easy to tear off by nail or cut off by scalpel.

Soldering was made by my 75W transformator solder, using lot's of resin. Pictures are not retouched at all and I did not even clean the board before taking the pictures. Board in question is Compaq Evo D310 one (MSI 6541 v1.0), exchange 10pcs of 1000uF 6.3V G-Luxon crap caps for 13pcs 1000uF 6.3V Samxon GC caps.
Board works well :)

[harleybro]

Yet another great addition to this thread! Trodas have you ever tried desoldering braid (http://www.tecratools.com/product658.html)? This stuff is really great. You place it on the solder to remove then heat up the braid from the opposite side with an iron. The braid absorbs the solder leaving the work area clean. This is really helpful for around small smd's especially if you dropped a bit of solder and it's causing a short. :hide: :lol:

[Shayd]

Yet another great addition to this thread! Trodas have you ever tried desoldering braid (http://www.tecratools.com/product658.html)? This stuff is really great. You place it on the solder to remove then heat up the braid from the opposite side with an iron. The braid absorbs the solder leaving the work area clean. This is really helpful for around small smd's especially if you dropped a bit of solder and it's causing a short. :hide: :lol:

:lol: I was just going to add that, good thing I read the rest of the thread :o

I work I-Level repair for a number of years and we used primarily the Solder Sucker and the Braid. The sucker for large amounts of solder that needed to be cleared from large terminals, but the braid worked best on the small stuff.

This is just my opinion, but I would personally think twice before recommending someone with low experiance using the big utility solder gun your using. I'd forsee a lot of burnt PCBs.

[madmaxx]

first off great thread Trodas :thumbs:

do you apply flux/paste directly on the board prior to heating?

that solder wick makes it look like even i could do this type of work :rotflmao:

[trodas]

harleybro - I never need it yet. Tin like to get sucked back to my soldering iron just by the heat of it, so... removal is very easy. Drop dead easy. All you need is keep the soldering end clean and use lot's of resin. Dip the soldering end into resin before doing anything and each time for each soldering attempt.


Shayd -
I would personally think twice before recommending someone with low experiance using the big utility solder gun your using. I'd forsee a lot of burnt PCBs.

Please take note that this solder has a trigger on it, so all I do is using a "burst" 75W and then nothing ;)

There is nothing worse than holding an iron on a component for a long period trying to solder/desolder. Not only does it potentially cause damage to the component, but it is really slow.

Hence with the 75W "burst" I never lifted a PCB trace with it or burned a PCB. Yet. And I did many recaps... just a very few for witch I did not lost (yet) pictures are linked there:

http://capsmod.net/forum/viewthread.php?tid=94&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=121&extra=page%3D2
http://capsmod.net/forum/viewthread.php?tid=130&extra=page%3D2
http://capsmod.net/forum/viewthread.php?tid=76&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=80&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=81&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=167&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=169&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=266&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=267&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=327&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=342&extra=page%3D1
http://capsmod.net/forum/viewthread.php?tid=346&extra=page%3D1
http://trodas.wz.cz/index.php?act=ST&f=16&t=337&s=

So perhaps you see what I mean there ;) Lot's of resin and only few sec per each cap/component. That it is. No damage from soldering ever.

But it is true that I started soldering when I was 6 years old. And recently I passed 33, so, some healty dose of skill is, of course, required.


madmaxx - thanks. No soldering paste, just dip the soldering end to resin each time I use it.


that solder wick makes it look like even i could do this type of work

It is likely you can ;) Just practice first on something that is already dead... later more practice on something that has very little value... and then mess with stuff your depend on :p

DIY is about the fun, and it is not much fun, when you kill things.
But once you get the knowledge, it is very easy. Sourcing good/well suitable caps replacements is usually way harder that soldering them :lol: (that is the ughly untold truth about recapping)

[Shayd]

Hey trodas,

First off, great article, don't take my comments as negative, as I mean them to be constructive.

I figured that was what 'you' were doing mate, just no where in your directions was that pointed out and someone that grabs a gun like that, again with no or little experiance, is without a doubt gonna toast something.

Also another tip, NEVER EVER EVER EVER use PASTE on electronic components! Its Acid based and will pit, desolve, eat your PCBs and components! Paste is for soldering plumbing fittings together! (mostly)

Always use RESIN, it will not harm the boards or components at all and can be cleaned off with isopropl alchohol and q-tips. Once the the bulk of it is gone a quick spray with a electronic cleaner will make it look like new.

I only mention this as someone said 'paste' and I bet they didn't know there was a huge difference.

[harleybro]

Since this is a cap thread I hope you don't mind me linking some info I have come across.

Badcaps (http://www.badcaps.net/)
capsmod (http://capsmod.net/forum/viewthread.php?tid=19&extra=page%3D1) Looks like it would be a great site but the forum needs some work. Actually see you posted there. :D
Lastly a capacitor (http://www.capacitorsupplier.com/index.htm) site. :thumb:

[madmaxx]

didn't know paste was different from resin, THNX!

@ trodas : in some of your pix it looks as if you placed resin on the PCB prior to removal/installion is there any reasoning for this or am i just seeing things?

[boshuter]

This is just my opinion, but I would personally think twice before recommending someone with low experiance using the big utility solder gun your using. I'd forsee a lot of burnt PCBs.


I have to agree with Shayd... if at all possible, do not use one of those type soldering guns. I'm not saying it won't work, it's just not the right tool for the job. If you already have one and can't, or don't want to buy a better iron, then it will work.

Just be careful with one of those, they have a very large tip (end), and if you are working anywhere close to smd's or bga chips, it could be a disaster. (you can remove an smd or bga with a hair dryer, so getting that large a heat source anywhere close to one can be bad ;))

I do agree with trodas, most people use too low a wattage iron. Replacing caps takes a good bit of heat, unlike most vmods, which require very little. The correct tool for either job is a good quality iron with replaceable tips, and if possible, heat regulation. I use an old 60watt Weller station and for vmods and working on small components and soldering wires on ic's or smd's I use a very fine needle point. For replacing caps, or soldering wires onto ground points, I switch to a large chisel tip.

This is an excellent guide to replacing caps.... but if you don't already have an old iron around, buy a good one to start with, it will make your life much easier. Todays hardware is very crowded with smd's and it's just too easy to heat one up enough for it to fall off. Plus, if you have the good iron you can easily replace those components, solder to them for vmods, and solder to the legs of the tiny smd ic's... you can't, or shouldn't do that with one of those large guns.

BTW; I know people who swear by that braid, for some reason, I have never been able to make it work for me. :o I will admit that I didn't try too hard, I have a desoldering station with built in vacuum pump that makes life soo much easier. ;)

[madmaxx]

i'm shure one can purchase smaller tips for the pistol style iron?

i've got a weller D550 any good for this type of work?

[madmaxx]

i'm shure one can purchase smaller tips for the pistol style iron?

i've got a weller D550 any good for this type of work?

anyone?

[boshuter]

i'm shure one can purchase smaller tips for the pistol style iron?

i've got a weller D550 any good for this type of work?

That is a 200w/250w gun...... it will work..... if you are real good.... and real careful. ;) :fire:

Sure wouldn't be my first choice though.

[ThugsRook]

nice work :thumbs:

[madmaxx]

That is a 200w/250w gun...... it will work..... if you are real good.... and real careful. ;) :fire:

Sure wouldn't be my first choice though.

thnx boshuter :thumbs:

the carefull part i can handle the good part not really shure as i've never attempted this, maybe time to head to goodwill and pick up some scrap PC's to play around on?

does anyone know if there are smaller/finer tips available for this model of iron?

i think i've got another weller kicking around here somewhere that may be less powerfull.

:beer:

[Shayd]

I was thinking that it would be worth the investment of a moderately priced station....and then I found this :yikes: He needs a bit of work on his public language skills but I think it just might work! :lol:

http://www.afrotechmods.com/cheap/iron/iron.htm

[Just Learnin']

He needs a bit of work on his public language skills

:yikes::hide:

[ThugsRook]

I was thinking that it would be worth the investment of a moderately priced station....and then I found this :yikes: He needs a bit of work on his public language skills but I think it just might work! :lol:

http://www.afrotechmods.com/cheap/iron/iron.htm
:lol:

anyone using a soldering iron shouldnt need detailed instructions on how to make a dimmer box, great idea yes but pretty self explanatory on how to make one :rotflmao: