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How to clear the non-clean residue out during soldering

christ

#25954

How to clear the non-clean residue out during soldering | 5 October, 2003

Hi all, We found there were some non-clean residue left on the PCBA,in all likelihood,they were rosin which couldn't be soldered enough,so I wish all of you can give me hints how to clear them out during soldering by correct reflow profile.

BEST REGARDS Christ

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#25962

How to clear the non-clean residue out during soldering | 6 October, 2003

Excess low residue flux is very dangerous to leave on your finished assembly, because it can: * Be corrosive to your solder connections * Promote dendrite growth.

To prevent this, follow your supplier's recommendations on: * Applying the proper amount of nc flux material. * Activating the flux.

Continuing with this idea, in the old days, people used a squirt bottle for applying water soluable flux during hand soldering operations. This was OK to apply excess OA flux, because it was washed off during a subsequent operation. Using a squirt bottle with low residue fluxes: * Applied in excess. * Much of it goes under components that were solder previously. * Never gets cleaned.

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christ

#25997

How to clear the non-clean residue out during soldering | 8 October, 2003

Hi Dave: I'd second you.Thanks for your effort and can you give me the hints about correct reflow profile for soldering PCBA.I doubt there was something problem during reflow,I found there were some flux residue left on the PCBA after reflow by the new reflow oven,but it was nothing left on the PCBA after soldering by another reflow oven,i.e,reflow profile was wrong.By the way,the new one was shorter than the old ovens, and there are 12 Zones in the new one,6 zones are setted on the upper side,and the others were setted on the lower side. Aiming at this situation,could you be kindly to give me some hints to cope with this problem.

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#26009

How to clear the non-clean residue out during soldering | 9 October, 2003

Start your recipe development with the recommendations of your paste supplier. The recipe in your new oven should produce identical results to your old oven [assuming you're using the same paste].

Given that your new oven is shorter than your old oven, if all other things were the same, you'd need to slow the conveyor on the new oven proportional to the change in length.

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