Ultrasonic cleaning pcb's with caps still on board

[Gabriel]

I have a macbook pro that has some smd caps that looks like some kind of Sanyo Oscon, I'm not sure they will hold up submerged in water-looking at svp datasheet I don't see any warning for submerging them.

I know some caps can't be submerged in liquid but will these ?

There is dried milk all over the pcb and I though I would dip it in my sonic cleaner too see if it would clean it up.

[stj]

Re: Ultrasonic cleaning pcb's with caps still on board

ultrasonic cleaning works best with IPA not water.
well actually it works best with FREON, but that's banned now - demonised for destroying the ozone layer when actually it was caused by high altitude nuclear tests!

[Gabriel]

Re: Ultrasonic cleaning pcb's with caps still on board

Hehe I'm worried IPA perhaps can destroy the small Apple plastic cable fittings, also the around the cpu you can see perhaps silicon or some other glue to fix the bga chips to the pcb.

The milk come off quite easy but I tought it would be easy the use the sonic.

[Agent24]

Re: Ultrasonic cleaning pcb's with caps still on board

If it's not in the datasheet there may be a separate document that tells you about cleaning and if the capacitors can get wet.. if in doubt maybe just ask Sanyo themselves?

[Ed Herdman]

Re: Ultrasonic cleaning pcb's with caps still on board

Maybe you could get away with not submerging the board fully?

Freon conspiracy theories aside, I don't see why plain old water (or alcohol) wouldn't be fine. It's a natural solvent for milk already, and I'd just try washing it first. As a bonus you could better avoid soaking things that way. Ultrasonic cleaning is probably overkill in this case, even if the milk is spilt. Cleaning PCBs with mounted components has never given me problems - though I don't run it over capacitors, they're not one of the components that I worry about getting wet. Just make sure it gets good and dry later. Also try to make sure that your final rinse is with distilled water, if you can.

[stj]

Re: Ultrasonic cleaning pcb's with caps still on board

probably not an issue here, but if you have a large pro-type ultrasonic bath.
as in many litres capacity and maybe even thermal vapor-recovery then you can damage crystals.

i dont think the small jewelry type ones can do any damage though.

[Gabriel]

Re: Ultrasonic cleaning pcb's with caps still on board

If it's not in the datasheet there may be a separate document that tells you about cleaning and if the capacitors can get wet.. if in doubt maybe just ask Sanyo themselves?

I see that some cap datasheets states solvent proof (within 5 minutes) or non solvent proof - Yes it's worth a try to contact them.
Problem is I'm not sure what series these smd caps are, looking at their colour I only guess that they are Sanyo.

Maybe you could get away with not submerging the board fully?

Freon conspiracy theories aside, I don't see why plain old water (or alcohol) wouldn't be fine. It's a natural solvent for milk already, and I'd just try washing it first. As a bonus you could better avoid soaking things that way. Ultrasonic cleaning is probably overkill in this case, even if the milk is spilt. Cleaning PCBs with mounted components has never given me problems - though I don't run it over capacitors, they're not one of the components that I worry about getting wet. Just make sure it gets good and dry later. Also try to make sure that your final rinse is with distilled water, if you can.

I bought 1L of sterile water yesterday, thought I just would rinse it after the sonic job. Not submerging the board fully is also something I have thought of - I guess I will just hold the pcb by hand in the basket for a few minutes.

probably not an issue here, but if you have a large pro-type ultrasonic bath.
as in many litres capacity and maybe even thermal vapor-recovery then you can damage crystals.

i dont think the small jewelry type ones can do any damage though.

Uhh didn't consider the crystal problem - you might be on to something.

My sonic comes from ebay - made a thread about it.

[stj]

Re: Ultrasonic cleaning pcb's with caps still on board

cool - ultrasonic deep-fat-fryer.
can it do chips?



i'd be a bit carefull with small crystals in that though - it looks pretty damn decent.

[Gabriel]

Re: Ultrasonic cleaning pcb's with caps still on board

Too small heating element to do chips or sausages, it can barely heat up water sadly - think it stops at around 70 C.

You can see the element glued to the tank side.

[a23d56]

Re: Ultrasonic cleaning pcb's with caps still on board

I use MAX contact cleaner (nozzle spray can) on motherboards. Dries fast.