### Constructing a Circle from a Cylinder

Similar to the cone and sphere circle constructions, this type of construction creates a circle from a cylinder at a height (or distance) along the defined vector. The resulting circle feature will have the same diameter as the reference cylinder. This type of construction takes three inputs: a height Value, a reference Point and a Vector.

Value - This box lets you type the height value. PC-DMIS constructs the circle at this distance from the selected reference point and along the selected vector. A positive value will use the same direction as pointed by the vector. A negative value will use the opposite direction along that vector.

Point - This list lets you define a reference point from which PC-DMIS constructs the circle. It has these options:

- CYLINDER_START - The start location of the cylinder. This point is located at the centroid of the circle defined from the first level of hits.

- CYILNDER_END - The end location of the cylinder. This point is located at the centroid of the circle defined from the last level of hits.

- ORIGIN - The origin of your coordinate system.

These images show some sample start and end locations for different cylinder types:

A - A sample CYLINDER_START location for an Auto Cylinder B - A sample CYLINDER_END location for an Auto Cylinder | A - A sample CYLINDER_START location for a Measured Cylinder B - A sample CYLINDER_END location for a Measured Cylinder

Vector - This defines the vector of the constructed circle and the vector along which the height value is applied. Eight reference vectors are available: CYLINDER_VECTOR/WORKPLANE/ZPLUS/ZMINUS/XPLUS/XMINUS/YPLUS/YMINUS.

Procedure to Construct a Cylinder Circle:

1. Access the Construct Circle dialog box (Insert | Feature | Constructed | Circle).

2. Select the Cylinder option.

3. Select a single cylinder feature.

4. Select the reference point from the Point list.

5. Select a reference vector from the Vector list. The direction on which the cross section is taken is chosen from the Vector list box.

6. Type a distance into the Value box.

7. Click the Create button.

The Edit window command line for this option would read:

CONSTR/CIRCLE,CYLINDER,feat1,HEIGHT,value,REF_POINT = point,REF_VECTOR = vector