G28, Easel and Z-axis probe

I have just learned about the G28 code, and it seems to work to get me to a constant work zero with my bump stock (which I also just made after reading the helpful posts), but I am having an issue with G28 and Easel. When I turn on the machine and home it (after securing my material), I go through the process of zeroing the z-axis, using the z-probe. However, my work home (as defined by G28) is at the corner of my bump stock and thus the corner of my material. If I move the router over my material manually, I cannot use G28 to get it back without exiting the “Carve” portion of the program, which negates my z-axis zero that I have set. My only solution is to zero the z-axis on the corner of the material, which does not seem accurate. Ctrl-Shift-D does not work after I have hit “Carve”. Anybody have a solution to this? I do not have the option of keeping my computer attached to the machine and/or keeping Easel open to save settings.

I’m a little confused by what you’re asking but this is what I would do:

Zero the Z, back out of the Carve menu, jog everything back to X/Y zero (G28) and then select “Use Last Home Position”. It should work but I haven’t personally tried it.

My understanding of Easel homing is it uses G54 for probe values so it will persist.

I will throw in my 2 cents worth here, John. I use G28 (actually G30 in my case) to zero the X & Y position from HOME. Then I use the Carve function in Easel to move 50mm to the right & 50mm forward. Then I use the Z-Probe to zero the Z position. As long as the board I’m carving is level it’s the same as zeroing at the corner but the Z-Probe disc does not tend to fall over the edge. Then I use the Carve function to move it 50mm to the left & 50mm back, putting it back on the original XY zero point. Now I’m ready to start the carve. Sorry for the long-winded explanation. I just hope it makes sense!

When you say manually do you mean pushing it by hand or joging with the commands? You should never push by hand. Just remember how far you move it. Best to use 1 inch increments, if you move 5 inch y and 7 inch x just move back 5 inch y and 7 inch x. When you are in your home position run your bit down to the table and make a mark, that way when you jog back to home your bit will be over the mark to confirm your home.

Thanks - I think that you and GordRock are describing a similar process. I was not sure that the jogging functions were “calibrated”. That process seems easy enough. And yes, I meant jogging rather than pushing.

Thanks. I have been afraid that “last home position” did not include the z-axis depth, but rather the height of the bit when it is at the x,y home. I did not want to risk breaking a bit or ruining a piece of material to find out

When you first start up machine use homing function, then enter g28 to get to your work zero at bump stop. For first carve when you probe click on directional arrows to your probe location. After probing use the arows to jogs back equal amount, then set xy zero.
Use last home is an option when you choose manual zero. It will use the last zero for x, y, and z. Example if using same material and bit again in another carve.
For repeated use of bump stop but different materials you can probe and use last xy zero.

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