Hit 10 years fixing boards and just found out I was using flux wrong the whole time

I was working on a old amplifier from the 80s last month, one of those silver-faced Pioneers a guy brought in. I always just globbed on flux paste from that little tin I got at a swap meet, figured more was better to get the solder flowing. This thing had cold joints everywhere after I worked on it, and I couldn't figure out why until a buddy stopped by my shop in Portland. He watched me for like 2 minutes and said "dude, you're using acid flux on circuit boards, that's for pipes." I felt like a total idiot. Been using rosin core solder forever but somehow never realized the paste I had was completely wrong. The worst part is I probably ruined a dozen other repairs over the years doing this. Anybody else ever get caught using the wrong flux for years without noticing?

3 comments

3 Comments

jordan_henderson1318d ago

Wait hold on, you've been using acid flux on circuit boards for a DECADE? That stuff eats copper traces like nothing. I'm honestly surprised you didn't have boards completely falling apart on you sooner.

quinn16118d ago

Two blown power supplies in ten years?

ruby65918d ago

The three revisions of my first PCB from 2014 all had copper traces that looked like a spiderweb by year two. I just kept slapping more solder over the mess and calling it a "reinforcement technique." Honestly I think the conductive dust from the corroded traces was what held everything together in the end. The board finally gave up when a trace for the power input literally turned into powder and I had to jump it with a piece of wire. Ten years of that nonsense and I'm shocked I only blew up two power supplies.