Homebrew PCBs

On Tue, 04 Jan 2005 10:45:56 -0000, Vasile Surducan <vasile@...-cj.ro>  
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? The same is  
true for PCBs.
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).
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.

ST