Press n' Peel as DIY solder mask

[bassmeister]

I had a thought the other day that you could use Press n' Peel as a DIY solder mask. Just make your board as usual, then apply the solder mask the same way as you apply the etch mask. This would require a software package that can generate a solder mask from a PCB layout, so you have to have the PCB layout files. I think there's an Eagle demo version that supports this function. Another, harder way, would be to invert an existing etch mask picture and fill in the traces with black with a graphics editing program (nice description of MS Paint, huh? ), leaving only white circles exposing the components' solder pads. This would make the circles exactly as big as the pads, which requires careful placement of the mask. Preferably, the circles should be a bit larger than the pads.

Pros: Generally, all benefits that there are with a solder mask, except that it's less durable than a real laminated one. I.e. less risk of solder bridges, resistance to oxidization of traces etc.

Cons: Is it really worth the effort...? Actually, I don't think so, but I haven't tried it. Maybe it's useful for those who are tired of searching for solder bridges and willing to spend an extra while on reducing the risk of getting them.

[Peter Snowberg]

Solder masks are for masking during wave soldering and after-protection is really more of a side effect. Resistance from oxidation should be applied with plating or metal coating. P'n'P will probably break down in the heat of soldering, leaving behind some carbon residue.

Sorry to rain on your parade, but I think technique and a clean tip are the best ways to avoid bridges.

[bassmeister]

...I think technique and a clean tip are the best ways to avoid bridges.

Me too, absolutely. I argued with myself if this was a very good idea, but I decided to post anyway. I haven't had any trouble with solder bridges yet, and I use a way too large soldering iron. I don't believe that carbon residue would be a large problem, however. To prove one of us wrong, I'll try it out some day . Of course the result depends on how large the spacing is relative to the pad (mask hole diameter minus pad diameter).