cleaning PCBs in an ultrasonic cleaner - what liquid?

[dfuruta]

Just scored a nice little ultrasonic cleaner for the right price (cheap).  Among other things, I'd like to use this for cleaning PCBs post-assembly - I'm not the tidyest when soldering, and my boards have flux and fingerprints everywhere.  Does anyone have recommendations for liquids to use?  I'm looking for something that's not particularly nasty (sharing a small apartment with the significant other and the fumes from soldering are already obnoxious enough), and something cheap or re-usable.

Possibly just distilled water and/or isopropyl?  I use no-clean flux.

 

[Script]

For cleaning PCBs, mix isopropanol (99%) and acetone at a 9:1 ratio (e.g., 90ml isoprop and 10ml acetone) and use an old toothbrush. You can buy both at almost any pharmacy.

If the pharmacy of your choice doesn't sell acetone, go buy nail polish remover -- same stuff.

 

[CJ]

we use plain water and then rinse with alcohol for a low impact solution,

get it? solution? 

you will smell what ever is in there due to the vibration causing it to fume,

it is the vibration that cleans, not the liquid, although it can help to use a light solvent,

 

[dfuruta]

Wouldn't acetone eat plastic/silkscreens?

Water & rinsing with alcohol sounds nice & easy!  I've got a little compressor I can dry stuff with, if I need it.

 

[PRR]

You generally want a grease-cutter. A very dilute dish-washing solution is usually effective. Ivory, Joy, Dawn, etc. 6 or 8 drops may be ample.

I can't imagine a pot of vibrating Acetone in a small shared apartment. And what if there is a spark?

Most nail-polish remover today is not Acetone. If it is, or isn't, it is usually cut with so much Lanolin that you are putting grease ON as much as taking it off.

> the significant other

If Other wears jewelry, after you get your technique down, you can clean the bling.

If anybody wears eyeglasses, the sonic-pot and a drop of Dawn is THE way to get the grunge out of the groves and hinges.

 

[Countrymetalguy]

I like using Everclear on PCBS, not super cheap, but not that expensive, and it has no odor. Just be careful, its uber flamable as you probably know..

 

[Rochey]

I just picked up an ultrasonic cleaner to do my Eden boards. (not set up yet, but it's there as soon as I'm ready!)

My plan is to use Isopropyl alcohol in the ultrasonic cleaner, then compressed air to blow the water out.

The most important thing I've read about this so far is that this process is done before adding any major mechanical parts, such as control pots etc.

 

[Rochey]

Hmm. don't listen to me,  I just started googling and came to the conclusion that the last thing I should do is use IPA.

 

[dfuruta]

Water + dish soap sounds even better!

The only mechanical parts on most of the boards I'll be doing (for now) are trimmers.  I use sealed ones from Bourns, most of the time.  The datasheet warns against ultrasonic cleaning, so I guess I'll put those on afterwards.

 

[Andy Peters]

Just scored a nice little ultrasonic cleaner for the right price (cheap).  Among other things, I'd like to use this for cleaning PCBs post-assembly - I'm not the tidyest when soldering, and my boards have flux and fingerprints everywhere.  Does anyone have recommendations for liquids to use?  I'm looking for something that's not particularly nasty (sharing a small apartment with the significant other and the fumes from soldering are already obnoxious enough), and something cheap or re-usable.

Possibly just distilled water and/or isopropyl?  I use no-clean flux.

I know I probably sound like a broken record, but at the day job (electronics design/manufacturing) we use a low-foaming, no-phosphous cleaning agent called Detergent 8 (.pdf) for board cleaning. It is designed for this purpose.

Dilute according to the directions, squirt on the board with a bottle and scrub with a toothbrush, or use your ultrasonic cleaner, rinse with de-ionized (NOT TAP) water, and blow dry with shop air. The bottle is expensive but will last forever for hobby/DIY use.

Alcohol really doesn't work all that well.

-a

 

[CJ]

heavy molecules need to crash into the board,

IPA molecules are too light me thinks,

unless it is Lagunitas IPA,

but why waste good beer when you can throw it up, 

check makers of those ultra-sonic cleaners, some sell the cleaning solution also,

 

[Andy Peters]

unless it is Lagunitas IPA,

I see your Lagunitas IPA, and raise you a glass of the Dogfish Head 60-minute IPA.

And I'm not saying that because the band for whom I mix live was paid to do a show at the 9:30 Club in DC that was sponsored by DFH and I have a bag full of their swag and oh by the way the club's system tech ensured that my glass of DFH 60 was never empty.

But yeah.

-a

 

[madswitcher]

I have used one of these for years and found that for most things, pure de-ionized water (the type used to top up the old lead-acid batteries) is the best with a couple of drops of washing up fluid to cut through any grease. Tap water contains too much contaminants and chlorine.  You can buy specialists cleaners but the name escapes me at the moment

Cheers

Mike