cleaning brownish solder paste residue
I recently was replacing an analog stick in my ps5 dualsense. I used the cheapest solder paste for the job, thats sticky and brown.
While the repair was a success i can't seem to get rid of all the brown shit it left on the PCB. I scrubbed it with IPA and toothbrush, and a brush. I even applied some heat but its always there. Cant seem to collect any more of it.
I already ordered amtech flux, and dont want to use that paste anymore, but it would be awesome if I could make my PCB great again.
Any ideas you guys might give me? I might add I'm like 2 years into microsoldering and I make numerous mistakes. Im no expert on this.
Some old rosin based fluxes can't be readily removed with IPA. In my service centre I utilise (cautiously) an acetone/methyl-ethyl ketone solvent commonly marketed in the USA as "Non-chlorinated break parts cleaner". Have to use caution to be well ventilated and not let it contact plastics (especially cases and polyproplylene capacitors) as it can dissolve them. It does however completely remove stubborn, old rosin based fluxes that have cured onto the board. Spray a small amount onto a small brush or a good cotton-tipped swap and wipe the offending area. It dries very quickly. It is quite flammable. All my other cleaning is with 99.9% IPA.
This is what I use, But it is not plastic friendly by any means.
Thank you so much for advices. I'll give acetone a careful go next time I have the dualsense apart!
I use MEK substitute. Sold at Lowes or Home Depot. In the paint isle. It will melt some plastic but I've never had an issue with it and pc boards or components.
You are using to much heat which bakes the stuff on to the board. Practice makes perfect as alex says and you need to create your own zone. You cannot do this just watching people do it. You have to do this physically yourself, But using common sense. Common sense is adamant, if you don't have this you will get nowhere. There are many layers to jobs like this, Patience, integrity and persistence.