Changing bits,to detail off set? Easier way?

When I do a 1/4 outline and then go to a 1/16th detail cut. The detail cut does not stay on the edge it cuts into the carving like it lost it’s X and Y a little bit. So the detail is off.Is there a way to zero it to where the 1/4 was cutting and the 16th can take over on the right path? Sometimes the detail cut is off by a 1/8. I guess my old eyes cannot “eye ball” it where I think it should be same spot. Hope people understand what I’m saying

When you change bits make sure you are ONLY zeroing the Z-Axis. X and Y should remain the same as the 1/4" bit.

Yeah it’s hard for me not to when I unlock the bit. Wonder if there is a way to clamp it? I think that is my problem is just that changing bit moving the x and y.

??? Nothing

Do you have Nema 23 motors? Is your grbl setting for $1 set at 255? If not set $1=255 and unless you are cranking down way too much on the collet to tighten the bit you should not be moving the X and Y axis when changing the bit.

yes I have the nema 23. My gantry is very loose I can push it around with one finger thought it was suppose to be that way.I do tighten down pretty tight. I can try what you said above $1 set at 255. But I think it’s because it moves so freely that when I un tighten collect it jumps.

I ran into this the other night… or rather noticed it for the first time. If you’re using the newer Xcontroller, there’s a switch on each axis to turn off idle voltage drop. This took care of my issue.

Which is what setting $1=255 may help => $1=255 mean that the motors are energised 100% of the time.
Atlas you will have maximum resistance from your system when changing bits. If that doesn’t help you a zero block is the way to go.

Another issue that can cause the defects you mention is actual bit diameter and actual width of cut.
Say you have a 1/8" bit, it measures with a calliper maybe 0.03" less and if you carve a single line that is 0.03" wider than 1/8". What you have now is an issue with a bit with incorrect diameter, with runout and tool deflection. All these factors are present in a larger or smaller scale, in any machine. You just need to be aware of it so compensation can be made.

If your not re-zeroing the bit each time you change them then you can introduce a slight shift in X,Y axis. Use a zero block as suggested. I use the Ttiquetra myself. It solved that issue.

Note: don’t do what I did and not measure the bit before hand and trying to zero using the code for a 1/8" bit for a 1/4" bit…

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