Newbie question on bit changes

Just got my Shapeoko Pro XXL up and running and it is awesome. I could use some help on bit changes though. I have bitsetter running and it is working fine. My question is if I am changing shank and collet size (1/4 shank to 1/8 shank) using bitsetter will my x/y zero be thrown off with the bit and collet change? I use bitzero to set x/y/z zero at begining of project then use a 1/4" down cut EM to clear out a pocket but want to use a 1/8 compression bit to do the final shape. Should i just do separate gcodes and re-zero everything after changing the collet and bit or is just using bitsetter ok? Hope this makes sense. Thanks for any help

Hi @Dhuston99

The BitSetter will automate tool length compensation for you, precisely for that scenario.
You just need to

  • save all toolpaths corresponding to your multiple tools to a single gcode file
  • make sure to follow the prompts in Carbide Motion, and never change the tool without either being prompted by CM to do so, or after using the change tool button in the interface.

When you run the job and it reaches a point in the file where a tool change is required, Carbide Motion will detect it, bring the router forward to let you swap the tool, and then when you resume it will go and probe the tool length difference, and adjust the Z zero automatically, and proceed.


Thank you. So change from 1/4 collet to 1/8 collet shouldn’t cause any problems?

No problem, when changing collets the X and Y centering won’t be affected (of course, because the tool is always centered on the router axis), and the Z difference in tool length (and how far you inserted it) will be taken care of by the BitSetter