If you don't trust yourself to break one open
then the next best thing
is one of the THIN saws made by Exacto. They're about 6 inches long and fit
in the large Exacto handle. The nice thing about them is that they have
FINE teeth (just right for cutting thin plastic) and the blade is very thin
so there's little gap left to fill when you glue the case back together.
The saw blade is about 1 1/4" deep and has a backbone on it to keep it
stiff. You should be able to find one in any good hobby shop.
When I have needed to cut open a wallwart nicely, I do it on a table
saw. This way I can control the depth of the cut, as well as having a nice
even seam. The only problem (and not much of one, really) is the gap that
might result from the wider width blades.
William Donzelli
aw288 at
osfn.org