End-Scan Using a Ball Probe

How to perform end-scans with a ball probe. Back to VTube-LASER See End-Scan Technique Research

About the Ball Probe End Scan Technique

This end-scan method is useful for situations where the only option is a ball probe - or where the Laser cannot reach effectively - but a ball probe can. Using a ball probe is very precise as long as the tube is properly held with a work holder. The main drawback with this method is that the tube must be securely mounted without deforming the shape. It must also be touched - thereby potentially moving the tube - which will invalidate most measurements.)

Measure Setup - For Measure the End Wall

Set Part Setup - Set the A-End Diameter to the diameter where the measurement will be taken. Set Measure Setup - LASER Tab: The LASER defaults to OFF for at least END-SCANS. Set Measure Setup - TACTILE Tab: Uncheck the Continuous Scan on Tactile End-Scans. Set Measure Setup - TACTILE Tab: Set the Offset for each end to "TOWARD BEND" if the measurement is on the end wall.

How To Use This End-Scan End Wall Technique

Align the probe the end of the tube as shown in the diagram below - take two points per quadrant. Press and release the green button for each measure. It is not necessary to take all four quadrants. Press the RED button when you are finished collecting data.

Ensuring the Proper Ball Probe Offset Direction

With ball-probes, the direction you begin your first and last straight section scan is very important. It gives VTube the ball probe offset direction. Follow these rules to project the point in the proper direction along the centerline: On the FIRST straight: The location of the first stripe must be as close as possible to the end - then scan away from the end. Do not allow any stripe to be closer to the end point than the first stripe. On the LAST straight: The location of the first stripe must be as far as possible from the end - then scan toward the end. Do not allow any stripe to be further from the end point than the first stripe.

How to Overcome Trouble With End-Scans

Check the A End diameter to be sure it is close to the actual diameter. Open the end-scan tolerance in the MEASURE 2 tab of the Systems Option menu. The default value is 0.039" or 1 mm. You can open this tolerance as high as you wish - for example you could set it to 0.750" (19mm) or higher and always get a qualified end. When you increase the tolerance, just take more care that you are collecting good end points. With tactile scans, it is possible to backup if you feel you have collected a bad point. Just press the button for "Red Button Removes Points" in the measure collection window, and press the red button. Then toggle the switch off to continue measuring.

Measure Setup - For Ends That Move Into A Surface

Set Part Setup - Set the A-End Diameter to the diameter where the measurement will be taken. Set Part Setup - Set the A-End or B-End Offset project the tube end point to the master end point location. A negative number projects toward the adjacent bend. A positive number projects away from the adjacent bend. Set Measure Setup - LASER Tab: The LASER defaults to OFF for at least END-SCANS. Set Measure Setup - TACTILE Tab: Uncheck the Continuous Scan on Tactile End-Scans. Set Measure Setup - TACTILE Tab: Set the Offset "AWAY" if the tube end is moving into a surface.

How To Use This End-Scan End-Into-Surface Technique

Align the probe the end of the tube as shown in the diagram on top of the end surface. Press and release the green button for each measure. It is not necessary to take all four quadrants. However, more are better if possible. Press the RED button when you are finished collecting data.

Other Pages

• See also End-Scan Using the End Wall
• See also End-Scan Using End Targets
• Back to VTube-LASER