--- In
Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
>
> On Tue, 04 Jan 2005 10:45:56 -0000, Vasile Surducan <vasile@s...>
> wrote:
>
> >
> > With all respect Steve, the photo's there are quite far away
> > from "commercial quality" as you named it. The problems begun
when
> > you need 100 similar boards with metalised through holes and
able to
> > be populate with just 0603 or 0805 series (and last one is
huge!).
> > With a high component density and other than 100 mil DIP
packages or
> > 50mil distance between pin to pin of SMD components. The other
> > problem is the silk screen if needs less (or equal) of 10 mil
> > resolution. Not the last one is the isolating varnish and thermal
> > and mechanical resistange of this.
> > And a huge problem is when you need for instance a 15x15 inch
board
> > (or any other bigger dimension where the printing error will
affect
> > seriously the board quality).
> > Prototyping yes. Very small series yes. But production never.
> > best regards,
> > Vasile
> > http://surducan.netfirms.com
>
>
> Vasile, production is not interesting because it wouldn't be
cheaper at
> all.
>
> As for the quality discussion, let me explain it differently:
> If you look at homebrew beer, do you believe one can make a beer
that is
> as good as commercial bear? Given enough time and devotion?
Hi Stefan, of course homebrew beer is alltimes better than
commercial !
>The same is true for PCBs.
Yess, agree, if you have 20'th, good eyes and you don't produce PCB
in this way for living purposes.
But don't forget, 20 flies away, glases on the nose come quickly
and beautiful girls are good just to look at.
:)
> The more money and effort you put in the better the boards will be.
> There are members here who make multilayer boards, with
throughhole
> plating. that is as good as it gets commercially. (add photo-
sensitive
> soldermask). At least one uses a inkjet so printing distortion
isn't an
> issue.
> Those people make great boards, for sure, but their setup is very
> expensive too. Nowadays you get a commercial board for 10 bucks or
so, but
> that isn't why they are making the boards, they do it because the
want to
> make that prototype _today_.
>
> Now, as said a multilayer - throughhole plating setup is very,
very
> expensive. If you can live with 2 layers and no plating it gets
very, very
> cheap (below 10 bucks equipment cost).
For this reason I'm staying on two layers even for production
boards.
> I can live without throughhole plating and multilayer, because i
get a
> board in under an hour and for less than 1$ in exchange. I make
component
> legend as good as a commercial board, but i don't do soldermask
simply
> because i don't need it and don't want to make a photo-process
setup again.
>
> So, you see, commercial quality isn't a question of possibility,
just a
> question of what you want to spend for it. At some point it gets
> economically not viable and the only reason you have for making
you own is
> very, very short time until you have the board in hands.
>
Now, be honest, how many boards produced in the indicated manner
looks EXACTLY the same? How many problems do you have when are
mounting SMD devices on those boards? Show me please a picture with
your highest desity PCB board, homebrewed.
best regards,
Vasile