Burying my bit when surfacing cutting boards

[CoachK10 (Roger Kollmansberger)]

Ok I have posted something similar before but have not found a solution to what I must be doing wrong. This is the scenario I a having happen when trying to flatten a board on my CNC (cutting board)…

1. I set the program making sure to Zero Out the x,y, & z coordinates - machine runs perfect
2. The problem is that at times I need to run the EXACT same program again to surface a bit more so here is what I do…
   A. I go back into the setting and leave X & Y alone however I do zero out the Z access because obviously the surface is a bit lower than previously
   B. After doing this the machine will ask me to install the surfacing bit which I do and it goes through the normal process
   C. When it begins it spins up normal, it then moves to the correct place, then disaster…

It buries the surfacing bit and the machine gets stuck which forces me to turn off the machine and wait at least 20 minutes for a reset.

How can I simply run the same program without this happening…it is very frustrating?

I have the Shapeoko 5

[WillAdams (William Adams (Carbide 3D))]

I wrote a bit about doing this sort of thing at:

Preparing rough cut lumber for machining

Given a rough piece of stock: [20240204_151557] one sets it on the machine, and if need be, adds shims where/as needed to make it as level as possible. and clamp in such a way that the entire top may be surfaced off [20240204_155540] set zero, then begin cutting: [20240204_171001] After running the file once: pocket_464x116_1mm_LOWERLEFT_TOP.c2d (44 KB) if a repeat is necessary, jog down to zero, then down by the cut depth of the file (1mm) set zero there and repeat — the zero may be …

If you continue to have difficulties let us know step-by-step:

• what you did — include screen grabs and notes on the values showing in Carbide Motion for position
• what you expected
• what actually happened

and we should be able to work through this with you.