-1

Just figured out why my solder joints kept cracking on old circuit boards

I used to just grab whatever flux I had on hand and go to town on vintage audio gear. After I ruined a nice 1970s Marantz receiver last month I finally looked into it. Turns out the old rosin fluxes don't work well with modern lead-free solder if you're mixing them. I switched to a no-clean flux pen specifically for mixed metal joints and my success rate went from like 60% to 90% on those old boards. Has anyone else had better luck using gel flux on older gear or am I overthinking this?

1 comments

1 Comment

holly_price1mo agoProlific Poster

Did you notice any difference in how the gel flux flowed into tight spots compared to that no-clean pen? I have been using paste flux on old gear and it gets messy but seems to wet the joints better on cracked pads. Wondering if the gel consistency gives you more control for reworking those fragile trace connections.