Difference between revisions of "End-Scan Using the Scissor Motion"

How to perform quick scissor motion end-scans.

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This end-scan method is useful for ease-of-use. Please keep in mind that our tests show that it is the least precise of the techniques that we recommend.

We also recommend the End-Scan Using the End Wall technique and the most precise End-Scan Using End Targets.

For tubes that don't qualify for either of the above techniques, we recommend end targets for ultra-precise measurements.

• The image at the right shows the end of a copper tube with a sharp burr and a highly reflective end-wall. It is very difficult to aim the laser at this end wall and ensure no outliers at the same time.
  
  
• The solution is to use white targets on the end of the tubes. The example here shows white poly labels that measure at 0.004" thick and provide an excellent flat target for the laser.
  
  (Note: Use the Plane-Point measurement in the built-in computer of the FARO Edge to confirm the thickness of the target.)
  
  
• The offset from the target to the tube end is entered as a negative value in the Part Setup menu for either end. In this case, we use -0.004" offset.
  
  
• Any shape of target works well as long as it is LARGER than the diameter of the tube. Apply the target so that none of the end-wall can be scanned by the laser.

When it is time to perform and end-scan, use the following technique to scan the target:

• Aim the laser at the target so that it strikes the target as perpendicular to the surface as possible. Avoid returning any points other than the target.
  
  
• Hold the laser still when collecting the stripes across the target.
• Consistently place the line across the same area of the target from measure to measure.

• The resulting geometry on the screen should appear like the image at he right.
  
  
• The end point generated on the screen should perfectly coincide with the stripes.
  
  

• If you prefer using more durable end target adapter that plugs into the end of the tube, then they can be manufactured for repeatable measurements.
  
  
• The end target surface should be painted or covered with a flat white or near-white target.
  
  
• The offset from the target to the tube end is entered as a negative value in the Part Setup menu for either end.