I just tried using a Dremel on a Dallas Semiconductor DS1287 real time
chip pulled from a PS/2 30/286.. I went down 1/4 of an inch (halfway)
into the chip before I struck metal.. and unless you're willing to wear
out your Dremel tip by removing all of the hard plastic around the metal
batteries, I don't expect you'll have much luck with Dallas timer chips.
There is no outer plastic box; it's all solid. I wish it wasn't; it
would be neat to see one that was hollow.
Daniel
I've not tried it myself, but I am told you can cut
away the top part of
the device using (e.g.) a Dremel tool, remove the old batteries and put a
couple of cheap lithium cells in.