Polymer Clay Disaster!

Over the weekend I made a lovely set of beads, I was really pleased with them.  I left them to harden up a bit overnight before I made holes and baked them.
So what did I do? I baked them without even making small guide holes for the drill (a small hand drill).  I've done that before and managed to make the holes afterwards, but it is always easier if I at least do guide holes.  When there are no guide holes you have to be careful to drill in from both sides or when the drill comes out the other side it can break off a chunk of clay.
I started with the largest bead and thought I was doing fine till the drill came out the other side and...  yes broke off a chunk of clay.  I was so cross.  It was only a small piece and I thought if I use a spacer at each side it won't show.   The middle size round beads drilled fine.  Then I started on the small beads and after the first three broke up completely when I started drilling I gave up!  I don't quite know why this happened but I have to just put it down to experience.

The photo isn't very good - the background of the beads is pale green.  I'm hoping I can make some more but the pale green was mixed from white and a bit of left over leaf green so I don't expect I'll be able to match it exactly.  Of course I should be really organised and record proportions and keep samples of mixed colours but I've never been that organised...
Oh well, onward and upward... well onward anyway!