How to remove flux
I’m getting some shorts in my Barton User Quantizer, and I’m curious if it’s because of too much flux around some of the joints? I’m guessing there are some flux “bridges” on the board because it’s so small? Isn’t flux conductive?
I’ve never bothered, but I was told that soaking a paper towel in alcohol, placing it on your PCB, and then rubbing it with an old toothbrush is a safe way to avoid getting the alcohol (and flux) all over your desk.
I use a cheap vibrating tooth brush and 90% alcohol. If you’re just using a tooth brush, go for the best bristle you can find (but don’t brush too hard). Brush with alcohol and rub the brush on a rag (white to see rosin fall off) to remove the rosin from the pcb. You’ll need to do a few passes to get the majority of it so it doesn’t scatter and stick to the PCB.
It’s necessary Since rosin flux is non-conductive, it can be left on the PCB. It should be removed because water soluble flux is CONDUCTIVE, absorbs water, and is slightly corrosive. In a pinch, very hot water and a little dish detergent would suffice. Preheat oven to 70-80 degrees Celsius and bake until it is dry. Isopropyl 99 percent alcohol is used to strip rosin flux. Make an effort not to have it on your face. The high concentration of alcohol is extremely hygroscopic, sucking all of the moisture from your skin. Fingernail polish remover and brake cleaner have the potential to damage components and the PCB, so use them at your own risk. You’re all working on circuits that can be affected by leakage currents, so keeping things clean will help.
Cleaning flux from a pcb, the easy way
This is highly dependent on the solder and flux you used. For recommended solvents, consult the manufacturer. Isopropyl alcohol or purified water typically cleans up no-clean flux beautifully. Chemical cleaners designed specifically for cleaning flux goop are also available. They’re available in aerosol containers, similar to hairspray or shaving cream. For keeping the residue out of cracks and crevices, I’d also suggest a strong stiff brush and a collection of dental picks. The typical rule of thumb at work is: I’ve had some issues at work with the crystals going haywire, and it turned out that the flux gunk was getting stuck in the leads of the Atmega128 and messing with the capacitance or resistance or both. Since then, we’ve followed the above protocol with great success.
Cleaning chemicals for PCBs and their delicate components are available in spray cans from GC Electronics. I’ve never had a problem with the CG line or any of the other brands that are specifically designed for electronic components, and I’ve never had them interfere with crystal activity.
Microsoldering 101 | perfect flux cleanup as you work
When soldering electrical components to a printed circuit board, flux is used. Flux is used to solidify the electrical link, depending on the components and form of solder used. To avoid inhibiting printed or engraved wiring and obscuring other elements, the residue left from applying flux paste or solder flux is normally removed. Flux removal from a PCB is an easy process.
2 Brush the solder flux onto the PCB with the toothbrush when adding the alcohol or acetone. Do not apply too much pressure to the solder point, as this can cause it to break. Repeat as needed to get rid of any residual flux residue.
Should i clean electronics after soldering?
I have a good looking purple PCB that I assembled with rosin flux from Laen’s batch service. I’ve cleaned the board as thoroughly as I can with isopropyl alcohol, which removes the rosin’s tackiness while also improving the dielectric behavior. However, as seen in the images, it leaves a white powdery flux residue that appears unprofessional.
I washed them effectively by scrubbing them with isopropyl alcohol and a trimmed down paint brush (to make it more firm for scrubbing). Then, before it evaporates, rinse it thoroughly with deionized (DI) water (I know, it sounds crazy).
Allow for enough drying time before blowing out the undersides of the ICs with compressed air. On that board, I had a lot of ICs, LEDs, FETs, other discretes, and even an LCD, and all three boards worked flawlessly and looked great.
A high concentration rubbing alcohol (the stuff I use is 92 percent and can be found at Walmart) and an acid brush will suffice at the hobbyist stage. If you’re on a tight budget, an old toothbrush can suffice if it’s cleaned first.