Ultrasonic cleaner residue

Hi,
I've tried a few different ultrasonic liquid types (Branson is not available here), sources for distilled water and types of 95%-100% ethanol/IPA. In all of my testing with combinations of these, I get a white residue on the boards. Any suggestions on what I'm doing wrong? The only thing I can think of is that I let the alcohol dry off naturally, without using ovens/fans.

Also, any tips on a good ultrasonic fluid available in the Netherlands?

Cheers,

Rick
 

peterfixit

New member
i hope ur not using IPA in the ultrasonic cleaner, that will lead to a fucked up day, just buy 99% IPA off ebay, and as for cleaning fluid just look at the msds of branson and find whichever is closest where you are
 

SMMRepair

Member
You don't really need to do alcohol at all...it's really not necessary. I did it for ~6 months, but hated the residue. Just clean as normal in ultrasonic then dry well. No residue, no issues. I've been cleaning/drying without alcohol for 6 months now and no issues at all. Water dries whether or not you apply alcohol.
 

peterfixit

New member
I dont get any residue, maybe try using a larger amount of alcohol, and filter it, i use a cheap broken ultrasonic cleaner just as a container for alcohol, its around 6 liters. after ultrasonic i put the board in the alcohol for 20 minutes or so and move it around, take it out hold it in front of a fan until there isnt alcohol dripping off it then stick it in the toaster oven for 20 mins at 120 degrees
 
Ok, the filtering sounds like something I could give a try. Thanks. I guess it all depends on the stuff you're able to buy in your region...
 

SMMRepair

Member
The alcohol is not needed for cleaning or drying a board. If you want to use it, that's fine, it certainly doesn't hurt anything (unless you consider residue a bad thing) but liquid dries regardless, period. You don't have to "force out" any liquid in order to dry the board. Liquid doesn't just sit idly in small microscopic spaces indefinitely. Liquid is fractal. The alcohol may "speed up" the drying process (but I doubt that, even), but it's certainly not required to properly and safely dry a board. It might be a good precaution if you're not a patient person, but to say it's necessary is simple not true.

Ultrasonic Cleaner --> ESD Safe Drying Mat --> Air Filter/Blower for 24 hours (or oven for 1-2 hours, depending). Boards are 100% and safely dry (like-new and without any residue).
 
Last edited:

G.Beard

New member
Hi,
I've tried a few different ultrasonic liquid types (Branson is not available here), sources for distilled water and types of 95%-100% ethanol/IPA. In all of my testing with combinations of these, I get a white residue on the boards. Any suggestions on what I'm doing wrong? The only thing I can think of is that I let the alcohol dry off naturally, without using ovens/fans.

Also, any tips on a good ultrasonic fluid available in the Netherlands?

Cheers,

Rick

I use ES132, CP500D, 99%IPA, drying oven and they come out looking new.

Let's have it right.... The customer wants to see a nice clean shiny board if they happen to take a look at your work. If your work is good electronically and mechanically, you should also have the boad looking nice and pretty and clean to because that is what the customer will see, IMO.

I find that boards look best after:

4 times through the crest (at 70°C for 2 minutes per pass) with ES132
Fresh 99% IPA for 10 minutes swish it around and a brush over with a tight paint brush
Oven bake at 90° - 105°C for 45 minutes.

I have no idea why or if anyone thinks the same but my experience so is that IPA and a good oven dry leave the boards looking new.
 

iambehr

Member
Hello,

If you are having residue after ultrasonic cleaning I would look at the ultrasonic cleaner. I have had this issue occur when I used a cheap chinese ultrasonic cleaner without a sweep frequency function.
Not sure if it was the cheap steel material of the tank leeching things in to the cleaning solution or the fact that it cleaned like crap because of the low quality of the ultrasonics, or because it did not get hot enough.

I use Branson EC clean at the recommended dilution, off the shelf distilled water, 60C temps, and a sweep frequency cleaner. The cleaner is a sharpertek that cost about $500. I rinse with 99% IPA and throw it in a toaster oven. The boards look brand new.

I'd be surprised if the ultrasonic cleaner is doing what it is supposed to do if there is a residue.

Stefan
 
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