Peter Barick wrote:

> I tried the suggestion by several to score the blank PBC on both sides,
> like one would w/ a glass pane, only deeper. Took it to the heavy table
> saw table with its sharp edge and tries to split it. NO GO, this for a 4
> x 4 inch piece. Even drilled about 6 fine holes on the score line across
> the board, still no crack.
>
> Guess what I need is a deeper score. May try again some time with a
> different tool.

That's because it's glass fibre mixed in a semi flexible resin. (Very
tough for it's size)

It won't 'crack' as such. Bending it will tend to tear the fibres apart
and pull them from the stressed out breaking resin, leaving a messy
edge. This can end up in unpredictable (costly) breaks.

Try this as a demo.

Cut a 1" square section out from the middle of a PCB edge.

-------       --------
      |      |
      |      |
       -------

The method I used was to cut down the sides with a hack saw and then
place the PCB in a vice such that the bottom edge of the cutout lined up
with the top edge of the vice jaws. I then used some flat nose pliers,
positioned close to the jaw edge, to bend the cutout section of PCB and
break it off. You will see that the section comes away nicely, but the
break is 'fluffy' at the edges and needs dressing by a file. If you
don't clamp both edges of the break line like this, the break will be a
lot messier.

You can cut reasonably straight edges along a PCB with a hacksaw if you
cut the board so that the blade is nearly parallel with it. You get much
greater control than by cutting it at right angles.

A band saw is quite good, but the blade can 'wobble' in the cut giving a
crooked edge, and you can veer of the mark if not careful, even with a
straight edge to follow.

You could use a router, but that requires some sort of jig setup and is
dusty.

A guillotine is probably the best, although hardest to get.


--
Best regards

Tony

mICros
http://www.bubblesoftonline.com
mailto:sales@bubblesoftonline.com

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