"Y" axis problem

[coop2739]

I am trying to carve a rectangular pocket .375 deep X 2.500 X 4.250 withr the 4 corners having a .500 radius. I have carved this same project hundreds of times but now I get 45-50% through the carve and the machine cut through the side wall past the end of the board. Whats wrong?

[AskBud]

I am trying to carve a rectangular pocket .375 deep X 2.500 X 4.250 withr the 4 corners having a .500 radius. I have carved this same project hundreds of times but now I get 45-50% through the carve and the machine cut through the side wall past the end of the board. Whats wrong?
How about attaching a photo of the bad board and the MPC involved! Also do you use a sled for this project?
Are other projects carving OK?
AskBud

[Digitalwoodshop]

Dull Bit....

Dirty Y Belt or Encoder....

Over 500 Cut Motor Hours bad Y Bearing in the Gear Box....

Gear box... Bet that is it....

AL

[coop2739]

Thanks Al I will take a look at the gear box. The bearings are probably bad as I have many hours of carve time on this machine.