I'm having a severe problem with solder adhering to the FR4 PCB material. I made my boards (myself, my first time) using positive developer and etchant on a pre-sensitized board. I washed the etchant off with nail polish remover.
It's so bad, I can take the iron and "paint" solder on the board. Flux (kester flux) doesn't seem to help at all. I don't know why this is happening or how to rectify it; searches on google only turn up page after page of people who just don't know how to solder (i.e., "solder won't stick to board."
Any advice or insight is extremely welcome.
I scoured it per the advice given below, and to my surprise, the "PCB" came off and revealed that even though I could see all my traces, the whole thing appeared to be copper. Considering I tried to follow instructions to a T, what could have gone wrong here and how do I fix it (or fix it on the next board)?
Now you will be bending the outer segments outwards a bit, which will move them upwards; I hope the PCB fingers are long enough so that they reach.
Best Answer
You've under-etched the board, or the photo resist was not properly exposed or developed to reveal the copper for etching (so it would definitely be under-etched in that case).
The way it works is that the etch resist prevents the copper from being etched away. When you are done you should be able to see light through the etched areas (and there still should be resist protecting the traces).
A photo would help, but it may be either that you did not recognize the appearance of an etched board or that something is funky with your etchant that is causing the areas being etched to not have a bright matte copper appearance. Here's a partially etched board where you can see the laminate partly exposed and the copper remaining.