PCB Cleaning

[fredwreck]

Wanted to get some knowledge about this.

No matter how many times I spray and clean this PCB with Flux cleaner, and a Qtip with Isopropyl alcohol.  It still looks murky!

What am I doing wrong? Why wont it clean.

Im using Kester 331 63/37 solder.

Thanks in advance!

 

[zamproject]

Hello

Are you sure the varnish don't melt ?

Best
Zam

 

[fredwreck]

Hello

Are you sure the varnish don't melt ?

Best
Zam

No the varnish didnt melt.  Just murky.  They say this is water soluble solder, but Im afraid to clean it with water on it.  what do you think?

 

[Bo Deadly]

Just googled Kester 331 and it states:

The residue can be completely removed with a simple heated water rinse. Deionized water is suggested to prevent introduction of chemistries from unknown water sources.

 

[Script]

For that I mix and use:
9/10 isopropyl
1/10 acetone

 

[Khron]

Are you having noise issues because of that? If not, and since most likely the board will be inside a metal(?) enclosure... I personally wouldn't bother :

 

[sodderboy]

I use miller stevenson or equivalent flux remover and a toothbrush.  If there are open thru holes on the board you have to mop the other side with solvent on a wipe or qtip to do a complete job.
I wear gloves as well.

 

[Ricardus]

First I use acid brushes with 99.5% alcohol. Then I use those foam "paint brushes" with the chiseled tip to follow up. If there's any murkiness left I use the blue paper towels (they're lint free) and use my index finger to clean it with some pressure. Beyond that I don't care. As long as it looks OK and it's not affecting the audio I'm fine.

 

[Whoops]

What am I doing wrong? Why wont it clean.

I always use this PCB cleaner solution/spray and never run into the same situation, it always gets the boards cleaned perfectly

https://uk.rs-online.com/web/p/contact-cleaners/8232634/