On Mar 15, 5:28*pm, " wrote:
Have a few year old DeWalt 733 that recently started behavior of
making a loud "thunk" noise as board is fed through machine. *When
this happens, the board stops dead in it's tracks (only for a
millisecond), it continues through, and then there is usually a divot
in the board where the thunk occurred. *It was a gradual thing at
first, but now it happens regularly. *I replaced the blades today with
new ones...same thing. *I cleaned the rollers with denatured alcohol,
have even tried 120grit sandpaper on them, and waxed the in/out feed
tables...same thing. *I'm planing poplar if it matters at all. *I'm
only planing 1/64" or so when this happens, but it happens at other
removal thicknesses also. *Is my next stop the service center??

Cheers

Sounds like it is skipping a tooth in the roller drive.
Best you listen to uncle Lew.