Step by step
Cut exactly around something already printed
A sheet of printed stickers or labels, cut on their outlines, with the cut following the print rather than the bed.
Before you start
Anybody cutting printed sheets: labels, stickers, packaging, printed ply.
- The camera calibrated. Do that first; this depends entirely on it.
- Your artwork, and the cut lines that go with it.
Print the sheet with its marks
The sheet carries registration marks in places the software knows about. They are what tells the camera where the print actually landed.
Print them at the same time as the artwork, on the same pass, or they are measuring the wrong thing.
Put the sheet on the bed, roughly
It does not have to be square and it does not have to be in a particular place. That is the whole point: a printed sheet never lands square, and the cut is going to follow the print rather than the bed.
Only make sure the whole sheet is inside the cutting area and flat.
Scan, and let it check its own answer
The camera walks the marks and reads each one, using each to sharpen its guess at where the next one is.
One mark is deliberately held back from the calculation and used to check the result. A fit that looks right but is not gets caught here, before anything is cut.
Cut
The cut path is bent to match the print, including the small stretch and skew every printer leaves.
If the sheet moves, stop and scan again. The alignment describes where the sheet was, not where it is.
How to know it worked
- The cut follows the printed outline all the way round, including at the far corner.
- It is as good at the edges of the sheet as in the middle.
When it goes wrong
3The cut is out by the same amount everywhere.
The camera calibration is off. Fix that first; nothing here can compensate for it.
It is right at one end and out at the other.
The sheet moved between scanning and cutting, or it is not flat. Hold it down and scan again.
It refuses to cut after scanning.
The check mark did not land where the fit predicted, so it stopped rather than cut a whole sheet wrong. Re-scan; if it keeps failing, re-calibrate the camera.