Homebrew PCBs

Hi,

It's not really that much spreading and is completely controlled by 
me...

I typically use 16 mil traces.  I use 10 mil as cut lines.  For 
spaces I go down to 5 mil, but I minimize putting too many "hard" 
areas on the board.  I can route 10 mil traces between IC pads, but 
I avoid them as much as possible to minimize touch up.  If I allow 
enough spearing to create shorts, I simply run an Xacto knife 
through the short to separate.  Only need a mil or two to avoid a 
solder bridge.  Picking the area to apply solder can also avoid 
shorts on tight areas.  Same deal if I under etch and have a short; 
use an Xacto knife to cut the copper and make sure I solder in a way 
to avoid creating a short.  I always apply enough solder to get 
a "wet" joint, but soldering from the right direction can avoid 
shorts in tight pitches.

I intentionally use the smallest hole size Eagle has for all of my 
pad/via holes and want them to start closing.  Maybe the way I 
described "closing" was misleading.  But on "loose" layout, I can 
almost close the holes and not create any shorts.  Whether this is 
too much "spreading" is subjective.  If it doesn't create shorts, I 
don't consider it to be too much.  I would never intentionally 
create more work for myself, but clearing one short is better than 
having to patch opens after etching.  I usually avoid too 
much "spreading" near my logo so the copyright mark doesn't turn 
into a blob.  When using an iron, I can be selective about the areas 
that get more or less heat or pressure.

If you look at the layout I posted in my album, you'll see that I 
widen all pads for improved manufacturability, solderability, and 
reworkability.  The design I posted didn't have the pads oversized 
enough, so in some cases, I had to be very careful about drilling 
the holes.  That was my prototype and I corrected any problems in 
rev1.  My goal is to route the board so it's easy to make.  All 
traces are sized so that minor pitting can be tolerated.  I touch up 
fill areas purely for cosmetic reasons.

Regards,
Dennis

--- In Homebrew_PCBs@yahoogroups.com, "Stefan Trethan" 
<stefan_trethan@...> wrote:

> That sounds like a lot of spreading - how small a 
trace/pad/spacing can  
> you get this way?
> 
> ST