I would check the x encoder for dust. On a carve the board moves in increments in one direction and a misfire might not be noticable. Not so on a cutout.
Do you have dust collection? I would next look at the x gears. There may be a tooth missing. The belts and their bearings may be fouled up with dust. Roll the x gears by hand and see how hard the belts are to turn. Look for a sources of resistance to belt movement.
I thought you were talking about the x motor encoder as well.
If you will indulge me on a suggestion... or not....
Rolled under Sand Paper Belts are very hard to see.... One suggestion and it is something I do all the time.... I turn off the machine and using a pair of needle nose pliers I puncture a hole in the sand paper belt under the cut motor on the keyboard side where the steel outfeed roller gap is for the out feed tray. I then rip off a 3/8 to 1/2 inch strip with the needle nose pliers pushing the belt toward the center of the machine and rip it off.... This will uncover a hiding rolled under belt and lower the board at the brass roller slightly to make better contact with the brass roller... It usually looses contace 3.5 inches from the end of the physical board when the board is possibly being held by less pressure due to only being under one roller or even the back or one of the in feed or out feed tables are set TOO HIGH.
Humor me... I know you did select to stay under the rollers.... What do you have to loose but a 1/2 inch of belt... The machine will work fine with the missing piece.... I rip EVERY belt as it creeps toward the brass roller... I always have a gap... I believe the belt creep is caused by me cutting more narrow boards like 6 inch and less 12 inch boards. This causes the belt to wear or get broken in and slightly bigger making a tapered cone from the belt.....
Good luck... I don't believe the brass encoder is at fault.
It won't hurt my feelings if you decide that the belt is not rolled under and not the problem... and dissreguard my suggestion....
Have a GREAT DAY... This is more for others doing a search in the future...
AL Who?
Favorite Saying.... "It's ALL About the Brass Roller"..... And "Use MASKING TAPE" for board skipping in the X or breaking bits.
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