Typically, This is one of 3 things:
-
Bit slippage: The bit is not clamped tight enough to stay in and during cutting forces, it moves or falls out of the router. Ensure you clean out the collet before inserting a bit. If you haven’t in a while, take the collet out and use compressed air to clean it and the hole it goes into the router free from dust. It’s possible your collet is worn out as well and needs to be replaced (this is a consumable part). Ensure you use both wrenches to tighten the bit into the router. Holding the red button is not usually enough clamping pressure. Always use both wrenches to tighten the bit.
-
EMI: Ideally, you want the router/vac on a separate circuit (not just outlet) from the controller and screen. When things are all plugged into the same outlet, or worse, the same (usually underpowered) power strip, EMI can be introduced and cause the controller to move unexpectedly. Also, if you run drag chains, having the router power cord run in parallel with the unshielded, delicate, motor wires is not ideal and can introduce EMI. Separate the router cord far from the motor wires. Lastly, we have seen instances where wiring running inside or outside the wall in conduit (like that of a power outlet) running near the machine introduced EMI. Try moving your entire machine 2 feet or more away from any close outlets, wire, or breaker boxes running alongside the wall. See also: EMI | Screen Flickering, Blank, or Black Screen, Randomly Loosing Zeros, Freezing, Disconnecting or Random Happenings
-
Improper Cable or Cable Connection: It’s possible that one or more of the 4 pins inside the axis wiring is not making a good connection and causing it to behave unexpectedly. If your z moves in the opposite direction than what it’s told to do, disregard the first two steps as it is ALWAYS a wire/connection issue. Check this link for more info: Troubleshooting: Rail is getting hung, stuck, or out of alignment (x35/x50 machines)
This is a test file designed specifically do diagnose Z depth issues: