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SE/30 Re-cap

derelictronics

derelictronics

Experienced Member
Joined
Jan 19, 2015
Messages
115
Location
North Carolina
I have an SE/30 collecting dust that needs recapped. I'm contemplating doing it myself (have the solder tools available at the local hackerspace). But, if there are people offering recap services for cheap enough, I'd be tempted to pay somebody to do it for me.

Can any of you recommend a somebody? If not, I need to find the specific capacitors needed. The values are listed at the site below. Maybe somebody sells a pre-packaged capacitor kit already?

http://www.maccaps.com/MacCaps/Capacitor_Reference/Entries/1989/1/19_Macintosh_SE_30.html
 
I forget who sells the kits at 68kmla - I think techknight - for about $10. Because of flat-rate shipping, it's probably about the same or a little more to order the caps yourself from mouser.com (not sure about digikey). I think 68kmla.org is probably a better place to ask recap questions. Maccaps is Uniserver's site.
 
Something like 11 caps or so? Well but if you do it properly it would still be an hour of work, maybe more if you also do testing and cleaning. And insured shipping to and from someone would be extra.

Forget capacitor kits, for under 5 dollar you can get a bag of like a hundred assorted caps and you'll be fine for the next 10 boards as well.

http://www.ebay.de/itm/120Stk-12-Va...400499?hash=item4d39c086b3:g:JfwAAOSwTapV7Oe8
 
kyodai said:
Forget capacitor kits, for under 5 dollar you can get a bag of like a hundred assorted caps and you'll be fine for the next 10 boards as well.

http://www.ebay.de/itm/120Stk-12-Va...400499?hash=item4d39c086b3:g:JfwAAOSwTapV7Oe8
Click to expand...

I doubt you will be doing yourself any favors in the long run by buying cheap capacitors with unknown specifications from fly-by-night vendors. Buy better caps (e.g. Panasonic, Nichicon, United Chemicon, etc.) of the appropriate specs, e.g.capacitance, size, voltage, temperature rating, ESR, ripple current, etc. from reputable suppliers (e.g. Mouser, Digikey, etc.). Ask on BadCaps.net if you need help choosing replacement caps.
 
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Uniballer said:
I doubt you will be doing yourself any favors in the long run by buying cheap capacitors with unknown specifications from fly-by-night vendors. Buy better caps (e.g. Panasonic, Nichicon, United Chemicon, etc.) of the appropriate specs, e.g.capacitance, size, voltage, temperature rating, ESR, ripple current, etc. from reputable suppliers (e.g. Mouser, Digikey, etc.). Ask on BadCaps.net if you need help choosing replacement caps.
Click to expand...

I took that route for years until I realized most of the time it doesn't really matter what brand or model cap you use for the really small values. While the above ebay bag-o-caps is not the way to go either, just look up the cap list and order what you need through ebay/Mouser and you'll be fine....or a kit off Technight.
 
Charles/UniServer at Maccaps is the man if you don't want to do it yourself. A1 work, and he knows these boards ( and most Apple boards) backwards and forward so he can also diagnose and repair any other issues.

Highly recommended.
 
Those SMD caps are a real bugger to remove, especially since 25 year old solder doesn't tend to want to melt properly again. I recapped my LC III motherboard and despite being really careful, I still managed to lift some pads.

You can replace them with more SMD caps (mouser has the best selection of these) or you can use radial caps by snipping and bending the leads. Radial caps are easier to place but SMD caps look nicer.
 
I recapped mine with radial caps (from a big bin of caps I keep on hand), won't win any beauty contests, but she works ;-)
IMG_0205.jpg

I was able to remove mine by rocking them gently side to side (if leads are north/south, I rocked east/west, GENTLY), this method worked for me on my Powerbook 100, SE/30, IIci, LCII, LCIII, and an IBM PS/2 Floppy drive.
 
I actually just started re-capping mine last night. I'm using a hot air SMD rework station to remove the old ones. It does lead to an occasional exploding capacitor, but it allows them to come off cleanly without risking traces. My plan it to replace the 47uf ones with solid electrolyte SMD capacitors having the same footprint (i.e. these http://www.digikey.com/product-detail/en/25SVPF47M/P16513CT-ND/4204320). They haven't arrived yet. EDIT: Here's the cart http://www.digikey.com/short/3t7cvb. Note I haven't tried out these parts yet, but they should work.

Old Caps:
Before.jpg

After Removal:
Caps Removed.jpg

Clean Pads:
Pads.jpg

Capacitor electrolyte slightly damaged the pads:
CloseUpPads.jpg

Non-exploded vs exploded cap:
Exploded Caps.jpg
 
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How exactly do you use a hot air station? I have one attached to my iron, but as I mentioned I've always gone for twist off. Do you liberally apply flux and just go at the thing? And what happens after it "explodes?" I don't see it conceptually. But your pads do look mighty clean.
 
raoulduke said:
How exactly do you use a hot air station? I have one attached to my iron, but as I mentioned I've always gone for twist off. Do you liberally apply flux and just go at the thing? And what happens after it "explodes?" I don't see it conceptually. But your pads do look mighty clean.
Click to expand...

One is supposed to pre-heat the whole board to reduce thermal stresses, but I don't have that tool and I've never broken anything without it. I set the air to 280C and heated around the capacitor in a circle to get the area up to temperature. After about 20-30 seconds, the solder reflowed and I plucked the part off with tweezers.

The few that exploded during this process were hot enough that their electrolyte boiled off all at once without leaving any residue on the board. The biggest mess was from the capacitors that slowly leaked over the years. A little bit of isopropyl alcohol removed most of the goo, and my flux removal pen (an ethyl alcohol, Isopropyl, and ethyl acetate blend) got rid of the rest.

To clean up the pads once the capacitors were removed, I added some flux and fresh solder to dilute the awful old stuff, then wicked most of it off leaving the pad ready for the new solder paste and caps.
 
I've done a couple of LC class machines so far...and after about the 3rd one, I'm quite comfy doing it. Charles (uniserver/maccaps.com) is certainly the leader in re-capping knowledge, and thankfully he is happy to share the knowledge for those willing to try it ourselves. Here's what I've started doing...

To remove them, I've found the twist-off method to work very well. Might be a problem if things are rotted out from the leaking capacitor...but sounds like that is rarely an issue. One person talked about using a tool that they could fit down over the cap and push down and twist. I've just used pliers...grab it hard, push down, and turn in place...keep twisting till it comes free. Most times it breaks off and just leaves a tiny part of the base within the pad. Sometimes, they twist around and the whole leads remain but the cap of the capacitor comes off freely. Either way, the hard work is done.

Next, I use some hi-grade isropropyl alcohol and q-tips to clean up as much of the capacitor goo as I can. That stuff seems to be pretty nasty fume-wise when you heat it up. Once it's mostly clean, I add a little flux around each of the legs. Then I use my soldering station (a cheap Yihua 936 from hobbyking.com) with a good Hakko chisel tip...put it against the pad, and it will pick the leg right up along with it...wipe it off on a sponge and repeat till they are all clear.

Next, I take a solder braid and use it to suck up most of the remaining solder off of the pads. Sometimes, if one edge of the pad is a bit messy, I'll run the chisel tip of the soldering iron around on it gently, and the flux tends to clean it right up. Once most of the solder is gone, get out the alcohol and q-tips again and clean up all the flux mess that was left behind.

For capacitors, I'm sold on the MLCC caps - I can provide a few example links if anyone is interested. They are a bit more expensive, but sounds like they should last a LONG time. They are also smaller, so there is lots of room to work with the soldering iron and pad. I tried the cheap exact replacements, but struggled to get them soldered in place. What I do is flow solder onto one pad, then use a toothpick to get the replacement SMD MLCC capacitor in position...then use the tip of the toothpick to press down on it while re-heating the solder I just place down. Now the capacitor is held in place. Solder the other side in, then if the first side isn't very pretty, go back and add a little more solder to it.

Someone somewhere once commented that once they learned to do it, they found replacing SMD caps easier than through-hole ones. After having done a few now, I'm beginning to agree.

Wesley
 
wesleyfurr said:
...
For capacitors, I'm sold on the MLCC caps - I can provide a few example links if anyone is interested. They are a bit more expensive, but sounds like they should last a LONG time. They are also smaller, so there is lots of room to work with the soldering iron and pad.
...
Wesley
Click to expand...

MLCC capacitors are great overall. Just watch out for some of the less-advertised characteristics of class II dielectrics, namely that their capacitance is voltage dependent and they lose capacitance with age (depending on the super secret formulation of the manufacturer). Life should still be great overall though. I'm imagining many hundreds of thousands of hours still. I chose solid polymer electrolyte capacitors mainly for the footprint and their long life (also should be many hundreds of thousands of hours at 45C).
 
Uniballer said:
I doubt you will be doing yourself any favors in the long run by buying cheap capacitors with unknown specifications from fly-by-night vendors. Buy better caps (e.g. Panasonic, Nichicon, United Chemicon, etc.) of the appropriate specs, e.g.capacitance, size, voltage, temperature rating, ESR, ripple current, etc. from reputable suppliers (e.g. Mouser, Digikey, etc.). Ask on BadCaps.net if you need help choosing replacement caps.
Click to expand...

I used dirt cheap capacitors countless times without any problems. I'd not be surprised if some of the expensive "premium" brands caps come out of the same frigging factory in China anyways.
 
kyodai said:
I used dirt cheap capacitors countless times without any problems. I'd not be surprised if some of the expensive "premium" brands caps come out of the same frigging factory in China anyways.
Click to expand...

Anything works in the short term, e.g. before the electrolyte breaks down.

For how little decent caps cost, and the value of your own labor in comparison, and the risk to your vintage hardware of leaking electrolyte or rework damage, etc., there is not much reason to buy the cheapest ones. If you are happy installing something you already have on hand then go for it, but I can't think that advising people who don't know any better to cut corners for so little benefit is a good practice.
 
CParish said:
I actually just started re-capping mine last night. I'm using a hot air SMD rework station to remove the old ones. It does lead to an occasional exploding capacitor, but it allows them to come off cleanly without risking traces.
Click to expand...

Instead of heating around the cap, why not heat the back of the board under the cap? I do that with BGA parts and I have less problems with cooked capacitors and other components.
 
NeXT said:
Audiophile effect.
It's brand name so it MUST mean it's good!
Click to expand...

Not quite. I'm not advocating buying gold-plated capacitors in the hope that it will make your digital music sound better. And it is known, for example, that United Chemicon (or Nippon Chemicon) KZG series have problems even though that is normally a good brand. But when your Teapo's are bloating, why would you buy CapXon (well known for early failure) when you could have Panasonic for very little more? I find recapping otherwise working equipment to be a big enough PITA that I don't want to do it any more often than necessary.
 
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