Tutorial: "Deep Cleaning" An Amplifier

Wow... this is an amazing tutorial! But the idea of putting a PCB with all its components soldered in place into a tub of water just gives me the shudders. :eek: My thought would be to use a moist soft bristle brush to give the PCB a good cleaning, with minimal water exposure.

The only trouble with this is, many units come with an "oily" sooty grime inside them that wouldn't just brush off. A deep cleaning is necessary. My Sony amp just came this way. I don't know where this stuff comes from. Maybe using the amp in a kitchen? :scratch2:

It would be good if other posters that used this method can post some before/after pics... TIA

I'll post my Sony TA-2650 "deep clean" as soon as she's finished. :thmbsp:

Thanks for the great tutorial.

Artie
 

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Great post. I heard the factory PCB has a 'coating' for protection (?).
What is it ? In audio restoration, littel is mentioned regarding this. Anyone?
 
Modern PCBs normally have the copper terminal pads plated with other metals in order to resist corrosion and enhance solderability, and the rest of the board, including all of the copper tracks, is coated with polymer solder resist. This process is called SMOBC for "solder mask over bare copper." The substrate is a fiberglass-epoxy composite material that does absorb and retain a small amount of moisture, but its effects are generally insignificant below 100MHz. Oddly, the cheap paper-epoxy material that's often seen in Asian audio gear is superior in this respect.
 
Help living in the UK i cant find Kleen Green Biodegradable Detergent has anybody got an idea of what I could use. I dont want to ruin a Pioneer A400 that I have found. Great Tutorial Many Thanks.
 
BinaryMike:
Thank for the epoxy composite info.
BTW. Is it true some use lacquer (clear paint) to coat after washing in restoration ?
 
Benzene was banned here as carcinogenic years ago. But I don't get why people freak out about acetone- you'll find it in most human bodies naturally. I've been splashing it all over myself for a few decades without ill effect.

Wait, maybe THAT'S what's wrong with me...! :eek:

There is always a paranoid treehugger in the mix spreading doom and gloom when all you have to use is your God given COMMON SENSE!!! Jon 56:thmbsp::thmbsp:
 
Cleaning Boards with Lemon Juice?

Thanks for taking the time to post this-I'm a noob here with some electronics background from my Navy time, and I know enough to know that I've a lot to learn-

Anyway,for my first restoration project, I pulled out my old 1984 vintage Yamaha R-50 receiver from the cellar, found what looked like dried mud(?) residue on the case and interior from what may have been an old plumbing leak-I found the service manual on Ebay(I'll scan and post later), but I googled "Cleaning Circuit Boards" and found this on ehow.com-

http://www.ehow.com/how_6200115_clean-circuit-boards-lemon-juice.html

Any comments from those who've been there/done that?

Thanks,

Jim
 
Help living in the UK i cant find Kleen Green Biodegradable Detergent has anybody got an idea of what I could use. I dont want to ruin a Pioneer A400 that I have found. Great Tutorial Many Thanks.

It is my pleasure.

Try finding any type of "domestic use" engine degreaser. But if that is not obtainable then you can use something like "Arial" washing powder (then the amp will have a nice flowery fragrance ;-)
 
Thanks for taking the time to post this-I'm a noob here with some electronics background from my Navy time, and I know enough to know that I've a lot to learn-

Anyway,for my first restoration project, I pulled out my old 1984 vintage Yamaha R-50 receiver from the cellar, found what looked like dried mud(?) residue on the case and interior from what may have been an old plumbing leak-I found the service manual on Ebay(I'll scan and post later), but I googled "Cleaning Circuit Boards" and found this on ehow.com-

http://www.ehow.com/how_6200115_clean-circuit-boards-lemon-juice.html

Any comments from those who've been there/done that?

Thanks,

Jim

Oh no no no! I would not recommend that. Lemon juice is an acid that corrodes copper and would be very bad for thin PCB tracks.

Just use some good thin liquid type degreaser/detergent.
 
My biggest wash stunt was a mixing desk with 34 audio channel modules! Nearly broke my back... but the desk looked just marvellous afterwards!
 
Help living in the UK i cant find Kleen Green Biodegradable Detergent has anybody got an idea of what I could use. I dont want to ruin a Pioneer A400 that I have found. Great Tutorial Many Thanks.
Simple Green concentrated All-Purpose Cleaner, is a similar product http://simplegreen.com/ & go to the Global Partners tab & you should be able to find the product locally.
I've used it on a Pioneer integrated with stunning results (thanks Machineghost). Next up are an A & R Cambridge A60, & Nad 3020i.
Cheers
Tony
 
Great thread machineghost. I'm going to use this one for any PCB based amplifier cleaning I do.
Thanks for your time and effort and obvious communications skills.
 
Im gonna find the dirtiest thing I can and give this a try after reading through 9 pages Im excited!

Think I'll use iso alcohol and distilled water for a wash on the pcb to remove the flux then, and let me get this right, you soak the whole populated board in a tub of detergent and water(even the pots and such), then scrub and rinse...albeit taking care of open chokes, enclosures and such. Then dry proper using induction and preferably compressed air.

Hi there!

Never soak the PCB and components. Work swiftly and work the detergent into the pots and give them each a quick few turns to help clean the track. Then rinse the PCB properly and dry ASAP. Do not bother with a pre-wash of alcohol and destilled water (you will be wasting your own time and money). Flux can only really be removed with benzine and/or thinners.
 
Gotcha, no pre-wash (use thinners for flux.) so im using the detergent right in the pots and such(on a tooth brush for the boards) (no water or diluted, just plain soap) then rinse like hell and properly dry?


Not sure why its a little hard for me to comprehend what your saying. Thanks for replying!

If you use a thick liquid type detergent then it would only be natural to wet the PCB before-hand with some water to make it spread a bit easier. But the type of detergent I recommend is something thin like KLEEN GREEN by Wynns.
 
I have done a Yamaha DSP series 5.1 amplifier today... came out good.

10514736_10152051333346642_7909792024539943981_n_zpsb16aa520.jpg


AFTER

10362624_10152051336336642_5132332893161681516_n_zpsee02e883.jpg


Came out nice and clean and works 100%. Had some nasty crap inside which caused it to cut out.
 
I have done a Yamaha DSP series 5.1 amplifier today... came out good.
Came out nice and clean and works 100%. Had some nasty crap inside which caused it to cut out.

That looks great. Thanks for the example. I have many that I am trying to perform the cleaning on but my other projects seem to push them to the back burner. I have been following this thread for quite some time now and I will post some pictures when I get a chance to get to one of them. :thmbsp:
 
Well done article including pics. albeit the subject piece was certainly worthy of this cleaning lesson.

If I may make a suggestion;
1. Unplug amplifier and allow capacitors to discharge.

Perhaps include a link to discharge capacitors. Just to be sure. A lot of 'later model vintage stuff has 5vcd circuits that don't like surprises.

------
I have rarely come across a piece like the OP but worthy of cleaning or perhaps just one board occasionally that needs it. I do recommend hand cleaning turner boards regarding the OP directions. Anything with adjustable stuff on them. I mainly hand clean units assembled as they're usually not that bad. Plastic tweezers and I make up some 'mops' using small paper towels and good supply of Q-tips. doesn't take that long really. brush off any lint.

For the OP's type work I use a dish liquid with a high surfactant quality, you know the brands that leave a shine on the dishes. Super dilute and along with the author I use a two long bristle brushes. soft nylon artist quality. rinse warm water and shake off the water. If no compressor or if in a hurry use a high volume blow dryer or just place a fan at it. Just like dishes you should get a nice sheen.

Lots of fun..:D till your better half starts handing you her stuff to clean.
 
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