Just venting a bit !! and maybe looking for tips…
I just did some really neat/nice soldering on the pixelblaze expander board…
I’ve got a temp controlled iron, good quality solder, and new tips that work nicely… the solder flowed onto the pads really nicely, and I got nice little volcano mounds to the pin headers.
Yay, I thought, I’m getting good at this !
Then I try soldering headers to some cheap chinese INMP446 mic boards… the pads and boards are miniature - so I’m working with a magnifying glass… and then the $#$% solder won’t flow onto the PCB board pads… it’s like the pads are solder-repellent.
I brushed a little liquid soldering rosin onto the pads and headers, but still wouldn’t flow. I’ve kind of got it to work - but basically a messy join now.
I think its probably the quality of the copper pads on the cheap boards ? Is there a way to prepare the pad surface better ? Any ideas or experience?