Need your help please!

[MikeSibley]

I know you guys are probably tired of me asking dumb questions, but dumb questions are how I learn.

I've been playing with my Aspire and AvidCNC because doing things allow me to learn. But I am stumped for now. I made a 3-D carving from two models that I got somewhere on the internet. I've made my pocket, put the models in the pocket, set a zero plane and cut the model which is my wife's family crest.

But, here's the problem. When I do an offset carving, it is leaving lines at the corners and it is leaving a false square pocket into the model. I've looked at it in Aspire, and there is no appreciable change in Z-height on the preview, so I am assuming that this is getting into the model via some software glitch or an error in machine setup/calibration. I can understand that the lines radiating from the location where the spindle makes the change from y-axis to x-axis being maybe an alignment issue, but not the box.

I leveled the spoilboard with a spoilboard cutter after first spending hours with a 1/2 inch spoilboard cutter cutting x and y axis 90% offsets and getting the machine aligned the best I could.

I have attached a couple of photos to show you what it is doing. Any advice as to what I am doing wrong would be greatly appreciated.

thanks,

Mike

[routalot]

I'm not sure I understand the problem,can you post an image of what the model looks like on your monitor?It does look as though there is a depth inconsistency that passes through a pocket and it could be the job moving on the machine,the tool moving in the collet or the Z axis losing steps.In other respects it look like a pretty good 3D job.

[BRAIN-HURTS]

It could be something to do with the cutting tolerance setting in your cam. The tolerance needs to be set smaller so that the cutter tip stays closer to the surface of the model.

[ger21]

My guess is a mechanical issue.
Maybe flex when direction changes, or a loose set screw on a pulley?

CAD/CAM Software is almost never the problem with issues like these. If the preview in Aspire looks good, then the g-code should be good.
And is the Preview in Mach4 doesn't show these lines, then it's not Mach4 either.