Originally Posted by
bergerud
There should be a little metal clip that the bit touches. (Older A machines just have the plastic with no metal clip over it I think.) If your board is much thicker than 1", the bit cannot reach it anyway. See the pictures. If that clip in the triangle is gone as well as the plastic under it, then you have the problem the people solve with the dime trick.
If that clip is there then your z stall is due to something else and you will have to explain just how and when the stall happens as well as what software version you are using.