Cleaning PCB

[IPv6Freely]

I finally bought some 99% IPA and used a (new) toothbrush to clean a PCB. Now it's sticky for some reason and the solder joints are dull, like they've been oxidized (I assume that's just the sticky residue, whatever it is).

What have I done wrong, here?

 

[pcb rookie]

One of my best compagnon to clean my boards: https://www.mgchemicals.com/products/soldering-supplies/flux-removers/flux-remover-for-pc-boards/

 

[Grubb]

Any tips for cleaning the component side of boards? I can scrub the back clean no trouble but getting in and around the stuff that runs through from the back is not so easy. And then there's always some left after soldering in pots and switches, which I have no clue how to tackle, seeing as IPA can damage them. I read a post on here from a guy who scrapes it off when it's dry but my flux didn't come off well doing that and left a powdery mess.

 

[Coda]

What about good ol' contact cleaner?
No, not the stuff for your corrective-vision lenses, but spray-can contact cleaner for electronics (I just picked up a can).

I've been using alcohol and a toothbrush, but not pleased with the results.

I start with a few healthy sprays of CRC. Then I go at it with IPA and a toothbrush, and wick it all up with a paper towel…

 

[SYLV9ST9R]

Any tips for cleaning the component side of boards? I can scrub the back clean no trouble but getting in and around the stuff that runs through from the back is not so easy. And then there's always some left after soldering in pots and switches, which I have no clue how to tackle, seeing as IPA can damage them. I read a post on here from a guy who scrapes it off when it's dry but my flux didn't come off well doing that and left a powdery mess.

I use Q-tips to clean the pot/switches legs, works great.

 

[Feral Feline]

I've switched to the MG stuff (IPA/Ethanol blend), cleaned my first time with it on a board the other night. Scrubbed with a toothbrush then wiped with a cloth. No sticky residue, but it did dull the board itself along with the solder joints (I inspected them prior to cleaning, all nice and shiny cones before the chemical clean dulled them).

Q-tips for the component side.

Straight IPA was just a gummy mess, the MG 4140 has the afore mentioned ethanol with the IPA, but I think the Ethyl Acetate is the magic ingredient (but I'm no chemist). Overall, happy with the results.

PS: I've got a 1L bottle of the 4140, but it also comes in a pen-like dealio, which I imagine would be great for the component side of our little noise-maker PCBs.

 

[Bricksnbeatles]

Anyone have tips on getting the PCB nice looking after all the flux is gone? I’ve noticed with the black PCBs that no matter how much I clean them, there’s always a haze left on the solder mask that takes a long time to buff away with a dry q tip. Just gotta put the time in I guess?
Edit: a dry soft bristle toothbrush does the job in 30 seconds flat; much better than the 30 minutes with a q tip I used to spend

 

[Betty Wont]

Anyone have tips on getting the PCB nice looking after all the flux is gone? I’ve noticed with the black PCBs that no matter how much I clean them, there’s always a haze left on the solder mask that takes a long time to buff away with a dry q tip. Just gotta put the time in I guess?
Edit: a dry soft bristle toothbrush does the job in 30 seconds flat; much better than the 30 minutes with a q tip I used to spend

I clean mine with a dry method that doesn't leave the film behind. I use a tiny awl and poke at the flux and it comes off completely in flakes.