X axis cutting too big?

[Weird Al CNC]

My name is Ian but everyone calls me Weird Al because I have pretty long curly hair, I've worked with cnc plasmas for right about 2 years straight out of high school. but i need some help So here recently our ArcLight Pro 4800 4x4 Table has all the sudden stopped cutting correctly. We only cut 1 thing on this table and one thing only it is a piece of angle that is 4 15/16 x 12. with these mousehole shapes cut out that are 4 1/4 x 3 5/16. it was working fine until about 2 weeks ago and then it started cutting these holes about an 1/8 to 3/16 too big on the x axis. we looked around the machine and notice a belt was pretty wore out so we replaced it thinking that might fix it but it did not it did the exact same thing. i was told to recalibrate the machine and i tried to my best ability but it still did not fix it. any suggestion would be greatly appreciated. i attached the drawing of the part onto this

[weldguy]

Try marking a starting point on the table, command the x axis to move 40" to the right on the X axis, then measure how far it went? Did it go 40", if not how much.

Now command it to go back the left 40", did it overshoot or undershoot the marked starting point?

[acourtjester]

Have you check to see if there is any slipping with the X axis drive components. For a test move the table in one direction mark the start and end locations. Then move it backwards the same distance. If Ok the table will move to each mark without fail. Repeat this a different speeds too.

[adbuch]

These are the dimensions I am seeing for your drawing. As long as these are correct, then you have a table problem - slipping belt, loose pulley, bad encoder, etc.

David