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Comment by gw99 | Hacker News Reader

Oh please not the flux over everything argument. This is completely wrong.

Buy a decent iron (metcal - get a second hand one off eBay) and some decent solder (felder 62/36/2) and you don’t need it.

Also don’t use a toothbrush with isopropyl. They tend to dissolve and leave crap all over the board.

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Agreed on the flux, agreed on the metcal. And oh yes, silver bearing solder is really nice. I only use it for repairs of solder joints that have failed mechanically. If you use it for everything, that solves that problem... but a little rich for my blood.

Hobbyists and technicians get obsessed with cleaning off flux. Hobbyists have no business cleaning flux off boards. It's very easy to wind up freeing corrosive salts from the rosin matrix. Then they smear all over the board to corrode and conduct. My rule of thumb is if you can't measure the cleanliness of your board, don't clean it.

Yep. To be honest a lot of stuff we didn't clean flux off professionally. Anything which was solvent safe would be soldered on, the board cleaned, then anything not solvent safe would be soldered on and it'd be left.

> Oh please not the flux over everything argument.

> felder 62/36/2

Other readers please note that felder 62/36/2 has a flux core. Which isn't clear in this comment.

Yes - I should have clarified that. The extra flux thing is the problem :)

I modified the "advice" a bit... What would you recommend to clean up?

Kimwipes soaked in isopropyl pushed around with some guaranteed 100% nylon brushes (usually the black ESD brushes are fine for this).

Toothbrushes bristles may melt. Not all of them are nylon and if they aren’t they will go sticky and this will wipe off on the surfaces.

Thanks, I keep that in mind for the next soldering project.

Check out 'Acid brushes' for use with IPA.

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