I have a very simple engraving (See attrached picture) and you will notice that one side of the engraving is wider than the other. The distance between the lines in each closed vector should be the same. This is a router that I built based on the workbee design and is running belt drive for x and y axis. The controller I am using is an openbuilds blackbox. I have checked the play in both the x and y direction of my machine. I have made sure the calibration in the x and y are the same. I have machined the edges of a sample board and checked that the corner is 90 degrees. I am hoping somebody can offer some advice on how I can correct this problem.
Does it happen everywhere across the machining area? Odd that the lines are spaced differently, but the terminal serifs are equal lengths in the exact same axis. Seems to rule out uneven screws. Maybe Y axis racking based on cutting direction? The right hand motor is leading the left hand motor, but not when it's a Y-only movement?
Quote: "I have made sure the calibration in the x and y are the same." Not sure what you mean, but both axes should be calibrated independently - they will not necessarily have the same setting in grbl after calibration is complete. Looking at those slopes in the pic, it looks like one of the axes is moving at a different "rate" to the other.
Can you do a couple more test pieces. Like the classic circle, diamond, square. Other, more predictable, test cuts. It may help is with some more insight into which axis is misbehaving. Also give all your shaft coupler grubscrews a tightness check
I think that what Peter meant was something like this It will give a better indication where the problem is.
Called the “Circle Diamond Square” test. It’s real name is “B-NAS 979; Composite cutting test 4.3.3.5” (;