Hey there, I’m hoping someone can suggest on how to scrape off this protective covering part so I can solder a wire to it. Because it seems like you can’t just solder on top of it because the solder just slides off.
I tried using a xacto knife but that didn’t seem to go well to get to exposing a solder point. Am I supposed to heat this up or something? How do you guys do it?
The protective stuff, it’s called the solder mask.
It’s pretty much a protective coating of heat resistant epoxy thinly applied before the board gets populated with parts.
You can scrape the material off with a knife, many of us do that. You can also use a fiberglass pen to “sand” off the solder mask.
You also want to apply some flux before soldering as that allows the solder to wet any exposed pads and traces.
I seem to be failing at the using a knife to scrape that material off. Last time I kept trying, solder still wouldn’t stick, and then I ended up scratching it up so much it was no longer usable.
I’ll try the sanding method to see if that helps with one of these fiberglass pens. What flux do you recommend?
You need to scrape gently, dragging the edge (not the tip) of your blade backwards.
You just need to clear off enough of that stuff so that you can see the shiny copper underneath.
Take off too little, and your solder won’t stick.
Take off too much, and you risk damaging the contact point on the PCB.
Yeah that’s the problem I seem to be having. I have not figured out how to take off just the right amount. And I’ve definitely taken off too much and then nothing works. I’ve gotten lucky a couple of times but I’m not even sure why.
Very frustrating.
I just use a No clean flux for electrical soldering, nothing special.