Been working on some Xmas gifts early, got tired of last minute. Doing the Xmas tree dish for family. Found the Cut Path which is offset by appox 1/4 inch ended up wider on one side than the other. Pic is attached. Happened on multiple carves, have run before with no problem. Checked MPC and did the formats and new uploads. Moved to card to second machine, 1/2 way through it gave a power fluctuation error. Tried repetitive proceeds but had to give up. A search gave worn brushes as one possibility and power supply problem another. Changed brushes and had same problem with power fluctuations. Swapped power supplies between the two machines. Ran MPC on the power failure machine and had perfect run.
Decided to change the Tracking Encoder on the first machine and see what failed. Ran two successive carves successfully. I can understand the changed encoder fixing the off-center tracking issue. Guess I'll have to wait for the 'other shoe to drop' on the power fluctuation. Had looked at the power supply for cracks and broken wires.