Who's done the SE/30 capacitor replacement?

[cangrande]

Hi all!

As I said in my Micron Xceed post I managed to snag a local SE/30 with horizontal-line video, and a logic board replacement fixed it. I've read the http://www.biwa.ne.jp/~shamada/fullmac/repairEng.html page but if any of you have done the capacitor replace (003 didn't you do it?) and you have any additional advice or parts sources I'd love to hear them. Might as well practice my logic board soldering. . . .

[equill]

... if any of you have done the capacitor replace (003 didn't you do it?) and you have any additional advice or parts sources I'd love to hear them. Might as well practice my logic board soldering. . . .

As far as I can recall, 003 had it done professionally, but TylerEss, JDW and most probably tomlee59 have all done it for themselves. There was good info. here before The Fall (to wax all Biblical for a moment), which may be accessible via PM.

de

[TylerEss]

I've done the capacitor replacement for a few folks from the forums, by mail-order.

My advice is to use regular radial-lead electrolytic or tantalum capacitors, rather than the tantalum chips recommended by Gamba.

The radial-lead caps don't look as clean and pretty on the board, but they make it much more repairable. In 15 years when it needs to be recapped again, it'll be easy to snip the leads and then remove them one-by-one, so you wont' have the risk of lifted traces nearly as much as with new surface-mount caps. I just bend the legs over into little "wings" and solder them down to the surface-mount pads.

It's a rewarding time spent with your SE/30 to do it yourself, if you have the necessary skills.

[Unknown_K]

How many caps (and different types) are there on the SE/30. I was looking at my IIsi and LC3 and noticed there are only a few sizes and values used for the can type of capacitors that leak. Do the tantalum surface mount caps leak as well (recangular ones)?

[TylerEss]

nope, the *little tiny* SMT caps are usually solid, and can't leak.

The caps I replace are the aluminum can caps, which usually come in two sizes: 47mF, 16V and 1mF, 50V. I also sometimes replace the bigger axial-lead electrolytics, which I have noticed leaking sometimes. IIRC, they're 470mF and 220mF at 16V.

[wally]

I've done four, two with aluminum surface mounts as a soldering experiment and two with solid tantalum radial leaded caps winged out as TylerEss suggests. Solid tantalums do not have liquid to leak, however they can fail by shorting. I do not expect to have to do another replacement of the tantalums in 15 years, but I might have to go looking for a failed cap and unsolder it to replace it.

The solid tantalum SMT chip caps commonly available have wide end connections that will not be strictly compatible with the close adjacent signal traces around most of the SE/30 existing caps. I prefer not to depend on the dryfilm resist to prevent shorts. The layout assumes a cap with narrow connections. I'm not against tantalum chip caps, theoretically they will filter some noise slightly better with less lead length. It's just that I have yet to see one that will fit the SE/30 layout, and I too like ease of future rework even if unlikely. So I'll stand with the TylerEss recommendations.

[TylerEss]

Another good thing about the radial-lead ones winged out is that it makes it easier to deal with the inevitable lifted traces.

If they're just slightly-lifted pads, you can solder to 'em as normal and then hold 'em in place with a blob of super-glue. (super glue can be removed easily with acetone, which is a normal part of the PCB-making process. Epoxy would work a little better, but epoxy is "forever")

If they're bad enough that you can't just glue 'em, you can cut 'em off, polish what remains of the trace, solder onto it, and glue *that* down.

With SMT caps you're stuck either using a jumper wire or remaking the trace using conductive epoxy, because you don't have the "just leave a little more leadwire on it" option.

[JDW]

While it's not possible to acquire Tantalum replacements for every single cap on the logic board, most caps can be replaced with tants. Any flavor of tants will do, SMD or dipped radial. You won't have to replace them every 15 years (or even every 30 years) like you will with electrolytics. But electrolytucs are cheaper and commonly found on most of our hobby parts boxes at home.

I've recapped one board with electrolytics and one with tants (yes, the boards function the same). I then used hot glue to secure the radial tants because the pads they solder onto can break off the board easily. (You won't have to do use hot glue if you use SMD tants.) By gluing radial caps down, there's no worry about breaking a trace by accident. And believe me, if you push a little too hard on a radial cap that's not glued, you will snap a pad clean off the logic board! This is an ever greater concern if you recap a board and then ship it to someone, because with too much external pressure on a non-glued cap, a trace could easily break. But of course, if you glue down electrolytics, then you will have to carefully cut through the clue a couple decades hence to replace them again. So this is why tants are a good choice for capacitor replacement because they will last as long as the logic board itself will (50 years? 80 years?).

The main thing you'll need in this replacement job is patience. If you have that, then you need the right tools. It's best if you have a tweezer soldering tip iron so you can apply heat to both sides of the existing SMD caps at once. It makes them easy to remove and it also lessens the liklihood you will break a trace (which often occurs if you desolder one side, force it up, and then desolder the other side). Of course, a tweezer tip is a bit uncommon, so most people just go the el-cheapo route. But you will need to use a continuity checker in the end to make sure no traces are broken. Otherwise you can bet on some unexplainable crashes and freezes when you're done.

It's really not all that hard to replace all the caps on an SE/30 logic board. But you have to be diligent and do the job completely and thoroughly. Don't have family members or kids around you when you start either. REPLACE EVERY CAP slowly and properly. Don't just replace 2 or 3 here and there because someone online said that would be enough. Replace them all. Why? Because they are old, leaking, and on their last legs (even if you cannot see evidence of leaking). And yes, I mean replace those two big caps as well, the ones with axial leads (you can use radial leg replacements if you want). Replace them all! Only then can you be 100% sure that your board is as good as new. Sure, sure, someone will come along and tell a happy story even though they didn't replace those axial caps. But those of you reading this need to do the job right and replace them all.

If after replacing all the caps the board still acts funny or won't work at all, there are other test and things you can try. But I must say this, I have one SE/30 board that is totally dead and cannot be resurrected, no matter what I try. It could be a bad chip, in which case you're better off buying a new board than to spend the months or years required to figure out the root problem. I've not been able to find the root problem on my dead board even though I have complete schematics and spent hours and hours on the problem! But not every board is like my dead board. Most can be restored to new operating condition with a good cap job.

Hope this helps.

[trag]

It's best if you have a tweezer soldering tip iron so you can apply heat to both sides of the existing SMD caps at once. It makes them easy to remove and it also lessens the liklihood you will break a trace (which often occurs if you desolder one side, force it up, and then desolder the other side). Of course, a tweezer tip is a bit uncommon, so most people just go the el-cheapo route.

The real el-cheapo route is to just use two soldering pencils. A grounded 15 watt soldering pencil is less than $10 at Radio Shack, so two of them will set folks back less than $20.

Get them both heated, and apply one to each end of the SM cap. Be gentle and patient and the cap will easily lift off with little to no danger of lifted traces.

This method of SM component removal was first posted (AFAIK and in the Mac world) on Marc Schrier's Clock Chipping Home Page, more than a decade ago, yet few people seem aware of it.

This also eliminates the easy-removal motivation to use radial caps instead of SM caps. However, the motivation because SM tantalums may have too wide terminals remains.

[TylerEss]

I think that clipping the leads of the radial caps and then removing each stub individually is still much easier than the "soldering pencil in each hand" method. I don't think it's as easy as it sounds, though it is invaluable.

[RoadApple]

Anything new I should know about a cap replacement on an SE/30 board since the nearly three years since this thread was last replied to? Thanks!

[Osgeld]

that I hate the clip and remove method, it leaves juice which made me nearly blow chunks when I got some on a soldering iron

[JDW]

RoadApple, there is nothing more to say in this thread because it pretty much has already been said. Follow the advice here and you will do well.

Osgeld, I don't believe many people really understand what you are talking about. I certainly do not. Snipping off a radial or axial lead capacitor with cutters and then desoldering the stubs of the leads that remain is indeed easier than removing the entire cap soldered in. The reason is because shorter leads mean less heat is required to remove them. Moreover, you can better pull the leads out one at a time when they are no longer attached to the capacitor.

[Osgeld]

yes but the clip n go method usually refers to smd electrolytic caps I misread the post above ...

seriously if you have issues with though hole components, ... well, and I disagree with the temperature issues, if your using a proper wattage iron there is absolutely ZERO reason to soak the part in heat, you should only be heating up the joint and pulling out a cap, 1 lead at a time is just as easy (if your doing it right you can just pull on it it with your fingers) not to mention the wonderful invention of solder wick making having to pull a though hole component a null argument anyway as they will just fall out

so (back to the question) you clip the can and remove the junk to easily remove the smd cap, the resulting fumes even after I thought I had washed the board down good made me feel very ill for a few hours

[JDW]

if your using a proper wattage iron there is absolutely ZERO reason to soak the part in heat...

Since we're talking about desoldering caps on the SE/30 logic board, not logic chips, I would like to add some thoughts. The above statement is correct much of the time, but not all the time. Specifically, when desoldering the two thru-hole axial caps from the SE/30 motherboard, it took a 450°C soldering station and several seconds of heat application before the lead soldered to the Ground Plane would even come loose. (Those of you who have desoldered those axial caps before should know what I am talking about here.) Since this is a multi-layered circuit board we're talking about here, a soldering wick wasn't much help to me (yes, I tried it more than once in the past on those thru-hole points).

So in cases where one of the leads is soldered to a Ground Plane (or a lot of copper traces on the PCB), you just might need to soak the lead in heat for several seconds with a very hot iron to make it come lose. Since you are desoldering a cap you've most likely clipped of anyway, it really won't do much harm to apply a lot of heat for a longer than normal period of time. Yes, there are limits, but so long as you keep the heat application to around 10 seconds or less, your board will be fine.

An alternative technique is to melt a lump of fresh solder on a fussy lead that is attached to a Ground Plane. Heat up that solder blob for several seconds and usually the lead can then be pulled out with ease by using a pair of needle-nose pliers. The point is that when dealing with Ground Planes you need a lot of heat and you will need to keep the soldering iron on the desolder-point for a longer time than would be required to loosen the solder on other connections.

But with regard to SMD caps, I was not thinking about using the clipping suggestion on these. Osgeld is correct that trying to cut off those caps would result in a big mess. I strongly recommend against that. I personally only clip thru-hole components. The easiest and least messy way to remove the SMD caps is either with two irons or with a desoldering station that has a special head for removing SMD caps. I have been successful at both methods.

[Osgeld]

Since we're talking about desoldering caps on the SE/30 logic board, not logic chips, I would like to add some thoughts.

I dont think the part matter much, its the board

The above statement is correct much of the time, but not all the time. Specifically, when desoldering the two thru-hole axial caps from the SE/30 motherboard, it took a 450°C soldering station and several seconds of heat application before the lead soldered to the Ground Plane would even come loose.
(Those of you who have desoldered those axial caps before should know what I am talking about here.) Since this is a multi-layered circuit board we're talking about here, a soldering wick wasn't much help to me (yes, I tried it more than once in the past on those thru-hole points).

I managed to do it tonight set at about 300, mixing hobby solder into a thoroughly heated, but not soaked joint, and added the pre-tinned end of solder wick and it sucked dry pretty quickly, its very important to hit the pad, the lead, the solder wick, AND as much area of the hole with as much iron mass as possible (chisel tips are nice, I dont have one, so its like holding a drumstick)

So in cases where one of the leads is soldered to a Ground Plane (or a lot of copper traces on the PCB), you just might need to soak the lead in heat for several seconds with a very hot iron to make it come lose. Since you are desoldering a cap you've most likely clipped of anyway, it really won't do much harm to apply a lot of heat for a longer than normal period of time. Yes, there are limits, but so long as you keep the heat application to around 10 seconds or less, your board will be fine.

An alternative technique is to melt a lump of fresh solder on a fussy lead that is attached to a Ground Plane. Heat up that solder blob for several seconds and usually the lead can then be pulled out with ease by using a pair of needle-nose pliers. The point is that when dealing with Ground Planes you need a lot of heat and you will need to keep the soldering iron on the desolder-point for a longer time than would be required to loosen the solder on other connections.

this is all soaking and it can be lessened by good joint contact, plenty of flux and some hobby solder to loosen things up

But with regard to SMD caps, I was not thinking about using the clipping suggestion on these. Osgeld is correct that trying to cut off those caps would result in a big mess. I strongly recommend against that. I personally only clip thru-hole components. The easiest and least messy way to remove the SMD caps is either with two irons or with a desoldering station that has a special head for removing SMD caps. I have been successful at both methods.

agreed

[phreakout]

I will refer you to my past post and what I offer if you don't feel confident to do the work yourself. Just buy an SE/30 Recap kit from 68kmla member Trag, send both the recap kit and logic board along with the ROM SIMM and some RAM to me.

I will do initial testing before any repairs, clean the board thoroughly of any corrosion, capacitor leaks, etc., replace all the caps on top of the logic board (C1 through C13), make sure all the SIMM sockets are cleaned of corrosion, replace the lithium battery (for just the cost of the part) and do a 24-hour period "burn test" to make sure the original symptoms don't return. In the testing process, I do multiple startup cycles, run stress tests on the video, RAM, etc.

My labor cost is just $10 per hour at about 2 hours per board. So really the costs come down to $20 for labor, $10 for the recap kit, optional $2 dollars for the lithium battery replacement (only if necessary), and then the cost of shipping everything to me. I'll cover the cost of return shipping, I won't charge you for the 24-hour "burn test" and I guarantee my work.

I've had a handful of members whom I've successfully been able to resurrect their SE/30s from the dead using my services. I not only work on SE/30s but extend to other makes and models, too. PM me and we can further talk.

73s de Phreakout.

[Osgeld]

Nice ad

[Paralel]

Would it be about the same for a Classic II? My logic board needs to be recapped and have some corrosion as well as rust on the external SCSI port taken care of.

[phreakout]

Sorry if it sounds like an ad, Osgeld. Just pointing out that I can do it.

Paralel, the same rates apply no matter what it is. I think a flat rate of $10/hr labor is reasonable. I'm just trying to put my talents to good use and help promote what we are doing here on this site.

We are of the same mind set that we refuse to overload the landfills with perfectly good retro macs and provide the best support possible to those who still own and/or operate these machines. You don't see Apple doing the same after a few years, do you? Heck, they discontinue more models and stop supporting them after 7 years, when the Macs still have a lot of life ahead of them.

73s de Phreakout.

[Paralel]

Awesome. Now I just need to crack that sucker open again and count caps to make sure I get the right number and type. I might post some pics here so someone can double check me, I'm apt to miss one or two if history is any indication.

[legalisi]

[New board participant introducing self] Hi folks!

I don't mind at all if phreakout's post sounds like an ad -- I need the service he provides and will be sending one or more SE/30 board to him for some work. Will keep everyone posted on the first-computer-I-owned resurrection process!

[beachycove]

SE/30 as first computer owned.... Did you buy it new?

[legalisi]

Yes -- it's one of the rare beasts that started its life as an SE (bought new in 1988) and I purchased the upgrade after a couple years. I used it heavily for years -- upgrading the RAM, adding an Micron color board to drive an attached Apple 16" color monitor, even using Apple's first external SCSI CD-ROM drive with it. I finally replaced it with a PowerMac 7500 and multiple machines thereafter.

However, like a guy's first girlfriend, my first Mac holds a special place.

JPL