On Fri, 29 Dec 2006 18:12:49 +0100, Dave Mucha <
dave_mucha@...>
wrote:
>
> As you know, there are may methods of doing a thing. Have ever made a
> small board to hold componets for a circut because you don't trust any
> other method ?
> And, it is very simple to use a resistor as a thru-hole instead of
> requiring a via.
> Many circuits can be proven, tested and corrected in-house on single
> sided boards. Heck, most shops are going to SMD parts, so holes are
> becomming less of a need.
> And for all SMD work, all you need is a way to etch the board. and
> for that , you might be better off with TT or some other such chemical
> method.
> So, for strictly SMD work, I would not recomend a drilling machine at
> all.
> Dave
Any _serious_ SMD circuit will require more than one layer and THP to
route it. Only the most simple circuits, or "old" technology, can make do
with a single layer. Things are getting smaller all the time and the only
things i still find single-sided is cheap televisions and very simple
circuits with only few components.
As you know i make all my own boards and quite a few that are not for
myself. I know the limitations for homebrew boards and can live with them,
for most projects. Some things just aren't physically possible, especially
some new components put high demands on layout, even if you are not
pressed by external size constraints.
I'm all for making your own boards, but i don't think the economics of a
CNC machine work out quite as was suggested. One can't buy a CNC and say
"right, now we'll save lotsa money because the design people won't have to
wait", a lot more goes into a PCB than what can be done with a CNC
machine. In some cases it may be useful, but the CNC may still not be the
most important thing for inhouse PCB fab, and in other cases it is not
reasonably possible at all to make useful prototypes yourself.
I believe quite a few CNC machines are sitting with a layer of dust in
various companies here, exactly because they were bought with false
expectations.
ST