Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan 
<stefan_trethan@g...> wrote:
> On Wed, 28 Apr 2004 08:03:11 -0400, Roy J. Tellason 
> <rtellason@b...> wrote:
> 
> > On Wednesday 28 April 2004 05:22 am, ballendo wrote:
> >
> >> 64x64" board size. .001" resolution. 16layers. Creates EXCELLENT
> >> gerbers/docs for the board house!
> >
> > That "layers" part caught my attention -- is multilayer stuff 
really 
> > practical
> > in a homebrew context?
> >
> 
> these are drawing layers i think, not board layers.

<snip>

yup.

a single layer board has 

Top copper layer
top paste layer
top solder mask layer
top silkscreen layer

drill map layer
drill hole layer
mechanical layer

seperate file/layer for NCDrill locations and/or Echelon drill file.


a two layer adds...

Bottom copper
bottom paste
bottom silkscreen



> Multilayer boards require the use of throughhole plating, which is 
> slightly complicated
> to make (and expensive). Some here have done it, and use it with 
success, 
> most (including
> me) fear the costs. 

I routinly make two layer boards but do not plate thru holes.  I find 
that by adding bottom traces and resistors or DIP chips, I can make a 
smaller board without adding to the costs.  Actually saving board 
material saves on costs.

I made a 4 layer board by overlapping 2 2 layer boards.  I needed 
huge power traces and could not get them to the TSSOP chip and add 
all the support caps and resistors.  Simple square posts standoffs 
carry the current.

Dave