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Subject: Re: [Homebrew_PCBs] Re: to drill or not to dril?

From: Stefan Trethan <stefan_trethan@...>
Date: 2004-03-26

On Fri, 26 Mar 2004 16:32:03 -0000, Phil <phil1960us@...> wrote:

> I dont disagree but once can over do it. I run traces between pads
> and would rather have the room there. Eagle libs use fairly
> elongated pads for IC leads.
>
> With a little practice, one can leave a lot of pad. In many cases,
> you have no choice. For example, double header rows - like an ICSP
> header (2x5) for programming an MCU. I put one on every project but
> there just isn't room for big ol fat pads.
>
> There is no substitute for skill/experience here.
>
> by the way, here's usefull drill conversion table
> http://www.thedirtforum.com/conversions.htm
>
> Phil


Pads designed for throughhole plated boards just are not to be used in not
plated
boards. it is simple math, the area is too small.

the 2xX headers are no problem, you could elongate them to the outside if
you really need.
the problematic items are e.g. plcc throughhole sockets. because there you
can't elongate
to the side and you need to run traces between pads. But there is still
enough room to make
it work.

I agree that there is no point in wasting space with unneccesary wide pads
but i also think
it is much worse wasting space (which is there anyway) and having the
copper lift off or a
remaining ring that is thinner than the track connecting to it.

especially for a beginner there should be no problem at all finding space
for pads...


ST

(O.T. does anyone know if Maxim sends samples to individuals without
company adress?)