Zoran,
I don't know about screen printing resist. Perhaps others have tried?
(Crazy because not more than 10 feet from where I'm sitting is a
complete screen printing setup. Not the film, though. We use the
liquid and a curtain coater.) If I weren't so busy with machines, I
might be able to answer your question.
But the real reason I'm writing is that it seems to me that the
resist and etch part of making boards is kinda solved... Through
holes too.
It's the soldermask part that IMO needs addressed. Anybody have a
GOOD DIY technique for soldermask? Can we screen print IT? (What
material do we use?) By material I mean goop, not cloth.
I did see the testor's paint idea. But as someone else wrote, if you
can solder "through it", it's not much of a solder mask is it<G>
Maybe more of a conformal coating...
Ballendo
P.S. I was really into the idea of inkjet printing resist direct
until the question about two sided board registration came up, and I
thought, "So much for that idea." Because I think it is going to be
much harder than some have written to solve this with the standad
feed of an inkjet.) I used to work on copiers, and even with the
better quality of registration rollers and clutches used there; there
is still a lot more variation than a reasonably "tight" 2-sided board
would allow.
But it would seem a VERY good idea to try to determine whether the
alignment needed for 2 sided boards is possible using the BEST case
scenario first. Using paper and inkjet ink. Because if you can't do
it with these, why would you expect that after... Changing the paper
path, adjusting for board thickness, and printing onto metal
(the "slickness" factor), is gonna make it work better!
It might be possible to do a soldermask that way though.(Since the
registration needs are only one side at a time, and a bit looser
overall.) Avecia has the material; it's just a matter of getting it
in small quantities, and figuring out how to make it work with "SOHO"
inkjets, as the inkjets it is designed for are the industrial HIGH
$$$ types... Neither of these will be easy, IME.
--- In
Homebrew_PCBs@yahoogroups.com, "Zoran A. Scepanovic"
<zasto@y...> wrote:
> have you any thoughts on using photopolymer films used for
silkscreen printing? I will try to obtain some samples and will post
the results.