Setting the toolpath Zero on a sloped object

At this point in my CNC career I should figured this out, but I need a nudge. I am working on a design hollowing out compartments in a 2x4 to make a geocache. The design turned out great, but my machining technique needs a bit of work.

I am basically making a container that is the full width of the 2x4 and it’s critical that I get the zero point right or I will end up with material getting shaved off of one of the sides and not the other (I don’t need material shave off of the side).

The challenge is that the edge of the 2x4 is beveled so finding the exact edge of the Y position is difficult. I don’t need to be so accurate for the X position since there is room for error there.

Here is what it looks like:

Any suggestions?

Not sure if need or want the beveled edge, but you could trim off the bevel giving you a straighter edge. Another option would be to get a piece of cardboard or stuff paper and line up the edges and use the corner of the paper to zero.

I do need the bevel. I’ll give your idea a try. Maybe cardboard will be stiff enough to do the job.

So why not use center instead of edge? I put a piece of painters tape on center and use ruler from corners to find center. After setting center by jogging and then remove tape.


Could you cut your stock out of a 2 x 6 to remove the beveled edges, then you should be able to cut without loosing your required size.

Make a fence tall enough to get past the bevel, then you can take Y off the fence instead (using a scrap with square edges). Butt the 2x4 against the fence and done.

I set up a fence so that it lines up with the ‘Quick Positions’ along the bottom. Once it was set up, homing is usually accurate enough that I don’t need to probe for X & Y - just jog to the SW quick position, and set Zeros there, then load my stock against the fence.

If I do want to probe, I can either use my stock, or a 123 block if the stock doesn’t have square edges.

I agree…use the center instead if able.

Hello. I have tried a couple of the suggestions here with good results. I am not great at setting the zero in the center because I am apparently uncoordinated. I am happy with how my test turned out.

Thank you to everyone for responding. That is what I love about this forum.


This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.