# DCF - Dual Cylinder Fit

## Contents |

## About the Feature

## DCF (Dual Cylinder Fit) is the major enhancement for VTube-LASER in version 2.8 (April 19, 2017) because...- It replicates measuring the tube TWICE in one pass when the user measures the tube the first time.
- It requires 4 total pass-fail checks for cylinder calculations.
The goal is to ensure repeatability of the cylinder measurements on-the-fly using a LASER scanner. |

## How It Works

When using the LASER scanner*, the DCF feature divides the cylinder surface data into two groups, then calculates the cylinder data and intersection points twice to verify repeatability. ## What happens if the points are too far apart?If the two DCF points are too far apart (the Point Repeatability value is too high), then VTube-LASER will warn you and ask for a remeasure. This allows you to remeasure the straight to guarantee that the measure repeats before moving to the next straight. ## What happens if the points are close to each other?If the two DCF points are near to each other within tolerance, then VTube uses the average of those two points as the final point. See the illustration on the right. |

## Introductory Video

See the five-minute video of the feature explained by Michael Cone - the developer of VTube-LASER. |

## MULTIPLE LEVELS OF CYLINDER FIT CHECKS

As part of the DCF feature, the Cylinder Fit Data window reports cylinder fit values that help you know if the cylinder measurement is good. ## CHECK 1 - MAXIMUM WOBBLE PREDICTIONThe ## CHECK 2 - CYLINDRICITY and OOR%The new ## CHECK 3 - INTERSECTION PASS DISTANCEThe ## CHECK 4 - DUAL CYLINDER FITAs mentioned above, because the DCF engine creates two cylinders, it always builds and compares the resulting intersection points from both cylinders. It warns you if they don't match well enough. |

## The CYLINDER FIT WINDOW is NOW COLOR-CODED for DCF

The Cylinder Fit Data window is color-coded to help you quickly determine where the problem lies in the data.
## RED PANELThis would indicate a major problem in the cylinder fit calculation. VTube requires a remeasure of a straight section. |

## GREEN PANELAll green indicates that no issues were found in all four checks. You can trust the calculation. |

## Intersection Pass Distance Warning TestThis is an example of the Intersection Pass Distance warning test. |

# Other Pages

- Back to VTube-LASER
- Back to VTube Software Updates (for LASER Mode)
- See also VTube-STEP
- See also VTube-STEP Revisions
- See VTube-LASER Customer Support Page to download the latest version.
- See VTube-LASER v2.8 - This is the version where DCF was first released