PCB Cutting

I have tried with tabletop scrollsaw from Proxxon-"DSH" (No:28092) and I can say that it works very well, but not with blades that are meant for it (No:28740-No:28744).

I had to use harder blades (No:28106) that are pain to mount in the saw, but they work very well and seem to take FR4 abrasion much better than serial ones. Quality of the cut is perfect and blade cuts closer to straight line, so there is much less need for "course corrections".

Regards,

Branko

Is scoring the copper clad really going to achieve a clean break? Seems to me you'd have to at least score through the copper into the fiberglass. Even then, would it necessarily break clean? Most boards AFAIK, are multi-layer, weaved construction. Very strong. ISTR FR4 "splintering" when broken, but that was without being scored.

For that matter, what about using a box & pan brake?

Agreed. If you score through something like 1/8th to 1/4 of the way through the board from each side, than the break isn't too fuzzy and doesn't cause delamination to extend too far into the board from glass fibers being pulled out of the matrix. After sliding the board along a piece of silicon carbide sandpaper on the bench, the edged can look pretty good. But, yes, the scoring needs to be more than a surface blemish.

A negative I haven't seen mentioned in this thread about sawing methods is the very hazardous properties of the fiberglass dust generated. It is one of the reasons I dislike any method that involved high speed cutters that disperse the dust into the air. I have had months of respiratory problems following such procedures.

I seldom use fiberglass for small projects or prototypes, so scoring and breaking works just fine for phenolics.

Depends on the size and accuracy required. Options I have used are: (#3 is the current choice)

1. Scoring both sides with a custom tool, basically a hook in an old piece of heavy-duty bandsaw blade, then snapping it.
2. A metal shear, but I understand it does the blade no good.
3. A scrollsaw then clean up the edge with a light touch on a belt sander. Odd shapes I cut out with a cheap air-nibbler.

Barry Lennox

points

excessive

It doesn't get any better than this:

In case that link is broken, start here and click on the little table saw:

This thing, with the carbide blade, makes an edge that is perfectly smooth and straight.

Love it!

Good day!

Nice!

...Jim Thompson