tracking issue

I am having trouble with the machine going off track when carving.
I attached two pictures to illustrate. The first one shows the lines and holes not aligning. I had three carves similar to this. At that point i took the machine apart and did a complete cleaning of the machine as per the 250 hour maintenance. I checked all the electrical connections. I put new brushes in the motor. the x drive gear assembly was replaced. I then reformatted the card. The next carve was better,

but still was off on one end of the carve. Any thoughts.Attachment 88938Attachment 88939

From what I can see it looks like the Z axis is giving you trouble. The Z axis is monitored by the tracking roller on the bottom of the board. Do you put tape on the bottom of the board for the tracking roller to run on? Imperfections in the wood can cause the roller to lose contact with the board. Taping the boards edge can stop this problem, if the imperfection is not that bad.

I agree with Mugsowner . Had a tracking issue myself and replaced the roller assembly. Took the old unit apart and found it full of fine dust. You might try cleaning yours.

I do have tape on the bottom of the sled. I will try cleaning the tracking wheel. Looking at the failed attempt there is a small glitch on the start end of all the boards and a bad alignment at the other end of the boards.

Good thing to check. Have had problems with bowing of the board from end to end causing tracking errors. Any small 'dip' going over the tracking wheel can caude either a small shift in the pattern or the machine stopping giving a tracking error.. Masking tape is a help as others have recommended and also check the rubber o-ring is in place. If it rolls back the tracking will suffer.

Head Pressure? Tape on bottom edge for tracking encoder. Seven inch rule.