Homebrew PCBs

--- Robert Hedan <robert.hedan@...> wrote:

> This is for Chris and the others that have yet to fiddle with SMD
> components.

>...  I used 1206 size SMD components, 0805 are even smaller but
> also harder to manipulate if you have a shaky hand like me.  Your breath can
> move 0805 components easily.
> 
I built myself a 'helper' finger. Out of coat-hanger wire I made a Y shape with
a loong foot. Then I bent the upper part square down like two feet. On the long
end I attached a needle, also pointing down. A sort of tripod. In the middle of
this three foot bridge I put some weight on.
Now you place any tiny component in place on the board and weight it with the
needle. Will not slip away and the sharp point ensures there is no thermal load
and no sight obstruction and you have both hands free.

> ...  I expect DIP packages to become harder to get over time,
> so I figured I might as well get used to them now.  One added bonus is the
> lower hole count.  I had started making my vias with wire, but now I use the
> leads on 1/4 watt resistors (or small capacitors, whatever falls under my
> hand); they are thin, hold in your fingers easily and I've got tons of the
> stuff.

I bend the DIP's pins outward with a flat plier. Now these 'old fashioned'
chips become SMD. HUGE counterparts to SOIC, but you need no holes and you can
place them on both sides of the board. All you need is a new package type with
your design program, 6, 8, 14, 16, 18, etc pads on 300x100 mil grid. Also works
fine with 600 mil 40 pin packages... No holes at all. (They look a little
clumsy...)
As these chips are not exactly flush with the board (well, they could be) there
is some place for 'wired' vias under them. If you are careful and patient
enough, very narrow pads will allow you to pass two signals between pads. Hard
to align and solder, but possible.

just some tricks...

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