Alan (Woody’s Workshop) has designed and made a hall effect tool height setter. Just a brief overview here, head over to Alan’s page where there are more details along with a PDF download that gives circuit design and full mechanical details – Hall Effect Based Tool Height Setter for use with PathPilot.
This homemade sensor works consistently to 0.001″. The electronic circuit is quite simple and could be professionally put together on a custom PCB. However, it is simple enough to actually string together the few components. As Alan put’s it, ‘bird’s nest style’.
The project is not particularly taxing and makes an interesting few hours of activity with the reward
of a useful piece of tooling to make CNC tool height measurement much less frustrating.
Click onto the link in this post to read Alan’s notes and to download the PDF that gives full instructions.