I just finished my first MPCNC build, and this latest problem has me baffled. The drawing looks great in the first pass and the first half of the second pass (cannot make it draw each line only once in estlcam). However, the machine gets off on the second half of the second pass on the right side of the image. Is it unreasonable to expect the machine to have better tolerances? If so, how can I eliminate the second drawing g in Inkscape or estlcam? If not, how do I eliminate the error.

How do you have the pen attached? How does my test code do?

It’s also possible the second pass is at a lower z, so it’s smashing the pen (and bending it). I can’t talk to the accuracy, because there’s no scale, but based on the scale I think it is, you will be able to do better than that.

The pen is attached with the recommended pen mount. The machine simple appears to be off by about .5mm and is not bending or squashing anything. The test crown works great.

Then I would agree with Jeffeb3, the second line is your issue.

The reason I asked about how your pen mounted and was looking for a picture is if you hold the pen really far from the tip your lines can do that. If you hold it real close to the tip and the 2nd pass is not too deep it should still be inline.

Have a look at my walk through and look at your depth of cut and your depth per pass one or both is wrong.

Go to coordinates 0/0, use a pen to exactly mark the position on the X/Y Rollers on the conduits, draw your thingy again (one time or couple times) and let the misalignment happen, go to 0/0 again and inspect the marks.

If its off, turn up the voltage of your drivers because you are missing steps.

Methinks I have tried everything with little to no change. I have tightened and loosened my belts and adjusted my pots both up and down. The only success came from changing to a fatter tip pen to hide the error. I will attach my dxf and gcode, to see if those are the problem. Also, can someone tell me how to stop estlcam from connecting lines so that some parts must be gone over twice? Note: I cannot upload my svg or dxf, but my gcode is attached.

powerPod.gcode (4.29 KB)

You didn’t try everything, well, maybe, because you didn’t answer back so it’s hard to tell actually.

Will you upload a picture of your pen as it is attached.

To answer your question, It’s probably going over twice because the depth is set lower than the depth per pass. If you set your depth per pass for that “bit” to be 1mm and ask it to go to 3mm, it will the exact same thing three times, but dive 1mm deeper each pass.

I also agree with Ryan, a pic would help.