Soldering

Greetings everyone. I’ve been dabbling with audio upgrades and soldering for some time; however, I’m now doing a diy Dac project and need soldering advice. I use Cardas flux and solder (seems like there’s flux in the solder, also). While I always get great results, the flux remains on the board as a paste. I use a qtip and alcohol to clean off the flux, but, it’s tedious and time consuming. Is there a way to expedite the process?

Any and all advice appreciated!

Thanks,

John
 
PCB cleaner and an old toothbrush works for me. You shouldn't need extra flux if your solder is rosin cored and the surfaces are clean and oxide-free. Clean straight after soldering, rosin hardens over time.

Unless a PCB is gold or tin plated or brand new (without fingerprints) it will need the oxide cleaned off as copper oxidizes in weeks rather than years. This is why commercial pcbs are normally tin or gold plated as standard.
 
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Ray a & Mark, thank you.

Yes, I tried soldering without extra flux, what’s in the solder is sufficient and makes less of a mess, as you suggest. The pcb’s are new, as are all the parts, seems no problem.

Thanks for the advice.

John
 
It can help to break up the flux first, using a toothpick or something that won't scratch the board. Then, spray on isopropanol, let it soak a while, and brush. Blow the dirty alcohol off the board and brush with compressed air. Spray on fresh isopropanol, brush, and blow dry again. This should be done outside where coating your surroundings with sticky flux residue isn't going to be a problem.
For cleaning up reworked areas, a q-tip dipped in isopropanol, and press and twist, then repeat with a clean end as necessary.
 
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Greetings everyone. I’ve been dabbling with audio upgrades and soldering for some time; however, I’m now doing a diy Dac project and need soldering advice. I use Cardas flux and solder (seems like there’s flux in the solder, also). While I always get great results, the flux remains on the board as a paste. I use a qtip and alcohol to clean off the flux, but, it’s tedious and time consuming. Is there a way to expedite the process?

Any and all advice appreciated!

Thanks,

John

This remover is mostly alcohol but with a few extra ingredients to improve it. I've been using this for almost 20 years.

4140 - Flux Remover for PC Boards

It used to be available in 1 liter bottles but it appears you have to buy the aerosol now.

 
This remover is mostly alcohol but with a few extra ingredients to improve it. I've been using this for almost 20 years.

4140 - Flux Remover for PC Boards

It used to be available in 1 liter bottles but it appears you have to buy the aerosol now.

Turns out the MG-4140 is available in a 945 mL bottle. California regs want me
to water it down 3:1 but that's not going to happen. Waiting for the alcohol based
remover I tried some Acetone. None of the components I'm using are problematic
with Acetone which is some of the best defluxer I've used AND it's cheap.

 
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