Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, "kg4wfx" <tony@e...> wrote:
> > 
> > > 
> > > The other thing I'm confused about is the solder mask (I think 
> > > that's what it's called) - the green layer commonly found on 
> > > production PCB's -is it possible to find this stuff and how 
> > > difficult is it to apply?
> > 
> > 
> > I wonder how to get the stuff everywhere but on the pads !
> > 
> > This is a thread I'd like to see get discussed.
> > 
> 
> This is an interesting one - I have found only one solution so far, 
> but I'm not sure how I feel about it yet.
> 
> There is a GC product called Red Insulating Varnish - this varnish 
> can be thinned with another GC product (which I can't remember the 
> name of off hand) - but from a vendor that I had purchased from in 
> the past, they had said that it has been done where you make a 
print 
> of the solder mask, and develop a printing screen for it, with the 
> thinner, thin the varnish to a point where it can be used in the 
> printing screen like a normal ink and viola (sp?) instant 
> soldermask/insulation layer.
> 
> Keep in mind I have NOT tried this yet, but I do plan to at some 
> point when I have my screen printer that I anticipate getting for 
> christmas.  
> 
> Also, it's a red coloring, so it won't look normal ;)
> 
> -Tony


OK, There are work arounds, but what do the board houses do ?

I was thinking a little brush on the drill so if you maksed first, 
the brush could scrape the mask off, but then that would have to be 
before thru-holes are plated.....

I would think the mask it last ?

Dave