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Sinisterdragon
June 7th, 2006, 05:08 AM
I would love to know how much cleaning up people do to their vintage computers... I was talking to a friend on the Net the other day and he was HORRIFIED when I told him my cleaning method for old PCBs.... I use a high presure water cleaner, then dry in the oven on low heat... I know it seems crude, but this is not disimilar to the method that are used in major Electronics production houses if they need to clean boards after production.. You have to watch out for water presure removing SMDs, and remove all batteries, but it works well...

http://www.pbase.com/sinisterdragon/image/61472914

For a nice before and after pic of a PCB.. I have not tested the board yet to see if it's working, but have performaed this on many PCBs and restored otherwise hopelessly crappy assemblies to good working health with no fuss... A tandy color was a classic example if this...

How far does everone else go?

The Sinister Dragon

alexkerhead
June 7th, 2006, 06:07 AM
I use a 160psi compressor with a 1/8" nozzle. Blows everything off the board not soldered on.
Water and oven are great if someone has tar slim from smoking on a board with coke and stuff on it.

atari2600a
June 7th, 2006, 09:22 AM
Didn't Steve Woz/Jobs carry food on the Apple 1 PCB's?

billdeg
June 7th, 2006, 09:58 AM
It's a case by case basis for me.

I never use the compressed water and baking method, too risky for me. I don't want to effect the component operation status. Baking new stuff is understandable, but old items have dust and crap on them and could catch file in an oven, and there is no guarantee that the water will get everything.

I opt for simple mild soap and water on the safe places like cases and keyboard caps. I only use compressed air outdoors, and only when I can be sure that I am not simply moving the dust around inside the chassis. I use a vacuum at a distance when it's safe to do so. Pure Isopropol alcohol on the sensitive components. I avoid Windex or cleaners except when that's the only alternative.

It can take many hours to process a new system into my collection. I also like to take a system apart as much as I can to get into the nooks and crannies without having to use compressed air or extreme measures.

To me it's a crime to take a dirty working system and turn it into a clean broken one, whatever the cause.

dongfeng
June 7th, 2006, 10:13 AM
I found for really dusty systems my petrol-powered leaf blower is very effective! It's great for blowing the dust out of old PSUs.

For light coatings of dust, a 1hp air compressor used for motor car tyres is usually good enough.

alexkerhead
June 7th, 2006, 11:25 AM
1hp would be about 90psi. 90psi is great, my 160psi(5.5hp), if you're not careful, can blow the caps off the board, so I use a 1/8 air spreader instead of concentrating the air. One foot away has eight inch blow area.

dpatten
June 7th, 2006, 04:11 PM
I work in the electronics industry for a major defense contractor.

I would have to recommend against baking or using a high pressure wash on a vintage board. Baking is fine for new boards. However, on reworked or vintage boards you run the risk of "popping" surface mount components or lands due to thermal expansion. Keep in mind that lots of these machines weren't manufactured to the highest specs to begin with and age causes circuit boards to delaminate.

When I clean my machines I use canned air and a brush.

If some putz spilled a coke in the innards, I use Isopropyl alcohol from the drug store. Its basically the same thing as the lab grade 2-propanol that I use at work. Make sure that you get the 91% IPA, not the 70% stuff as there is less dissolved water in the alcohol.

Plastic stuff gets warm water and dish soap.

Just my $.02

Chris2005
June 7th, 2006, 04:32 PM
I will wash a board or whatever if it's skanky enough, or use a commercial spray to remove oxides (I had to do that to my Tandy 2000 ages ago - I was having problems so I bought this stuph from Radio Shack, pulled the socketed chips out, sprayed the whole board and chips, let it dry thoroughly, reassembled, and it worked like a charm). Absolutely nothing wrong with water and some mild detergent, and a wee bit of brushing, but there's normally no need to do anything more.
Yet, I have this old TI PC that became a habitat for...well I'm not sure. Years ago I had my old Chevy van parked on the side of the house, and used it to store a bunch of stuph lol. Well...one day I pulled the puter out and fired it up (or tried to). Fan wouldn't even spin...crap. So I opened it up and there was all this shredded paper and insulation stuphed all inside. Trouble is I can't see mice or whatever having any means of getting in. I don't think insects would have gone to all that trouble. And the board was corroded in spots. Nothing horrible, but I'm not sure water and detergent will take care of that.

Mad-Mike
June 7th, 2006, 05:56 PM
System Boards - I usually use Q-Tips and Isopropyl Alcohol, usually only if they are rather dusty, or if the pins on stuff looks to be "abused" (tarnished/rusty), though sometimes I just dust em' off dry.

Casings - Usually Oxyclean, Windex, 409, or anything else that comes in a spray bottle, and a rag.

atari2600a
June 7th, 2006, 07:28 PM
I once accidentally used (wood polish? Not sure what it was, but it came in a spray-pump bottle & was used for wood) on my TV (Thought I grabbed the Windex) & for at least 2 weeks, maybe the month, it acted like a barrior againsed fingerprints & dust. I know it has barely anything to do with the topic, but I thought I'd just share that with you guys...

digi
June 24th, 2006, 01:43 PM
I've stuffed many, many circuit boards in the course of my job, and since I use flux, I always clean them afterward. What has worked well for *me* was to use some very hot running water and a toothbrush. I have never had any surface mount devices come off, and everything works just fine after you give it a drying off with an air compressor. This method should work fine for just plain dirty boards, although some rubbing alcohol ought to do an excellent job as well.

Unknown_K
June 24th, 2006, 08:18 PM
I strip the circuit boards from the case first. The cases either get windexed if fairly clean or scrubbed with soapy water if dirty. Motherboards and cards usualy just have a bit of easy to remove dust so I use a q-tip to dislodge most of it and then vaccum it off followed by a paper towel and some windex to removes anything that was left. For cables I get a couple pieces of paper towels soacked with either soapy water or windex and run the cables through a few times while squeezing the paper towels over them.

So basically liquid soap/water and/or Windex works for me.

compu_85
June 26th, 2006, 09:10 PM
I have found that a Mr Clean Magic Eraser works great on old plastics. It takes the dirt right out of grungy keyboards. You do have to be careful though, if you scrub too hard it can start to wear the finish or remove lettering.

Windex and paper towels clean up the reside leftover.

I had tried running several old (junk) keyboards through the dishwasher, and I don't think they survived. Glad I tried it with some extra units!

-Jason

Sinisterdragon
June 27th, 2006, 12:32 AM
I have used the hi presure cleaner sucsesfully on first some scrap keyboards, and then some old Apple II keyboards... they now both work well and sparkle like new.... especially one keyboard that would have otherwise been thrown out, something sticky had been droped on it and keys where sticking in the down position.... No risk of removing the surface or the printing as it's only soap and water.... Took a long while to dry, you have to pay attention to the heat in the drier, or you will melt the key tops..... Bit of patience and eureca!!!!! Fixed keyboard.....

Computer Collector
June 28th, 2006, 07:02 AM
wont doing all that rust it? this sounds nutty to me. Ive never done anything like that. Ive blown into the holes to get dust out, though.

Sinisterdragon
June 28th, 2006, 12:54 PM
I started experementing with high presure water as an means to clean items that would have otherwise been unservicable yet I was reluctant to throw out.. I have worked in electronics production most of my life and knowing thats how it's done when cleaning is needed in production, thought there was nothing to lose trying it on older electronic equipment. All the metalwork on equipment I have come across has SOME sort of anti corrosion treatment, I have never noticed a problem. Especial since for the most part the cleaned object is dried in temperatures of around 40-50degC and dries fairly quickly....

DOS-Master
July 4th, 2006, 04:48 PM
http://www.implementations.co.uk/shop_images/perseus_rake.jpg :D :D

Unknown_K
July 5th, 2006, 08:55 AM
I started experementing with high presure water as an means to clean items that would have otherwise been unservicable yet I was reluctant to throw out.. I have worked in electronics production most of my life and knowing thats how it's done when cleaning is needed in production, thought there was nothing to lose trying it on older electronic equipment. All the metalwork on equipment I have come across has SOME sort of anti corrosion treatment, I have never noticed a problem. Especial since for the most part the cleaned object is dried in temperatures of around 40-50degC and dries fairly quickly....

I have seen plent of circuit boards where surface mounted components are barely held on with solder, using high pressure water will send those parts flying around never to be seen again.

Sinisterdragon
July 5th, 2006, 12:54 PM
I have seen plent of circuit boards where surface mounted components are barely held on with solder, using high pressure water will send those parts flying around never to be seen again.


In my origainal post I said you had to be careful, but I have never had this problem, and high presure water is comanly used in electronics prodution to clean PBAs including those with SMA on board.... doesn't look like there is much solder there some times, but the bond is actually quite strong...... I have HEARD this is something to watch out for, however the only time I have known SMAs to be removed is in one instance when the was an equipment malfunction, and the high presure nozzle contacted the board, scratching SMA components off as the board went through the wash..... I have seen tens of thousand of PBAs washed this way in electronics production without any real problems......

Chris2005
July 5th, 2006, 03:51 PM
"wont doing all that rust it? this sounds nutty to me. Ive never done anything like that. Ive blown into the holes to get dust out, though."

There's usually little danger of rust, regarding the circuit boards anyway. Oxides...a possibility, but there are solvents that can make short work of those. I bought a pair of Imacs at a puter show recently...were well rained on/in. I allowed them to dry out for a couple days (wanted to do it longer, but got antsy). They worked with utterly no problems. Most of the ferrous (iron based) type metal on the boards, resistor leads etc., are plated anyway. Rust only occurs between ferrous metals (iron, steal) and water. Other non-ferrous metals could react slightly with the addition of water, but usually nothing to speak about.
If you're exposing the innards of a power supply to excessive moisture though, that might be a little different. Funny though, I pulled out this old AT & T 6300 DOS mostly/semi-compatible unit I found in someone's yard LOL. I had seen it while driving by at least a half dozen times along route 9 in Freehold. I had thought of taking a picture and posting it on a website with the caption "Who says vintage puters are hard to find". It had been sitting there for who knows how long. Snowed on, rained on. I disconnected the cabling from the "motherboard" and video card (it's monitor runs of 24vdc IIRC), and turned it on. Sure enough the fan spun, and the 5v lines read 5v, but the 12v lines read 11.41vdc. Not sure what that's a result of. And funny thing was the cpu card was missing! So maybe it was defective to begin with...why it ended up in someone's yard.