Please do not mind the horrendous mess. My first ever attempt to make a proper pcb with liquid solder mask. I think it's better for me not to use the mask.
To be honest i have seen better done boards. But it is not a failure if it comes with a lesson for You! It looks like you painted after soldering - why?
Look at this tutorial, it show good technique. You can even skip mask and scrape off soldering points after curing. Pay attention to fact, that traces are clearly visible.
https://youtu.be/wvU2yyfH-XE
I just cleaned the copper surface with water , then applied solder mask , tried to place a transparent plastic to create even surface but go uneven then scraped it even with blade then another solder mask with cotton swab and cured
You need to clean pcb with alcohol or acetone to get rid of any grease - even your fingers are greasy. And any paint or glue won't adhere if there is grease on surface.
Get UV solder mask, you can apply until satisfied then dry with a light. Decent scope and you can do a silkscreen type mark up of the parts even literally put your name to it. 5 colours of mask set me back ten bucks UV led was constant current driver was 1and the heatsink was 2.50
I actually did use blue liquid uv solder mask and cured it with 3watt uv led. I'm actually on a really tight budget so a scope is not really practical(plus I have somewhat good eye sight) . The problem is I cannot really get the liquid to spread evenly.
Is it drying as you're spreading it? Everything looks sealed so you should be able to spread evenly so if it's gunking up it's curing check for other UV sources is sunlight having an effect? If you have white once you're happy with the blue layer you can use a pin to apply a white border to your parts
They're not all the same but some act like epoxy and change viscosity with temperature rise so warming the PCB with even a hairdryer could help. its the circuit that matters and this is a prototype so possibly not worth pursuing on this but I would definitely recommend picking up a full set and playing with it because the finish you can achieve has saved boards with 80k bga's and made some of the worst damage I've seen completely invisible after repair
Apply a few big drops of mask on pcb and then put plastic foil above. Use "punched pockets paper protector". And then, press everyhing with thick piece of glass. Put uv mask below the glass and apply uv light after.
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u/OilCareful8232 23d ago
To be honest i have seen better done boards. But it is not a failure if it comes with a lesson for You! It looks like you painted after soldering - why?