I knew when I saw it that it would someday bite me and it just did. So now I have a nice gouge on my table
This is the tool release button on the Z axis and not the one on the control. Anyway, for those of you that have these buttons and do not want the same experience as mine I found a very nice solution, go to most any gun shops and ask for a number 01 Objective flip up scope lens cover by Butler Creek. This is a perfect fit over the tool release button and has a spring-loaded flip up that quickly allows access. Even if left up one has to deliberately put your thumb or finger in to push. This should eliminate any accidental tool release.
Ken