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NY Signal drawn by 3rd PlanIt

TrackPlanning.com

NY Signal drawn 
with
3rd PlanIt by Walter Griffin

Click to visit 3rd PlanIt forum


3rd PlanIt offers a wide variety of tools to draw curves and circles in your drawing. A Curve is a portion of a Circle with a constant radius throughout the curve. A Transition Curve is a special curve that changes radius smoothly from one end to another. Transition Curves are used to connect two curves of different radius, or to connect a curve with tangent track (straight track). With 3rd PlanIt, Transition Curves are drawing easily and automatically in combination with the objects they connect.

3rd PlanIt has a handy feature to alert you when circles or curves are less than your minimum radius. When you are drawing a circle or curve, it will be drawn in red unless its radius is greater than the minimum for the current layer. When its radius is above the minimum, it is drawn in black. Click for animation

Drawing Circles

Click to view animationComplete circles may be drawn using the Draw From Center and Draw From Tangent tools. If you have the Radius locked in the Object Data Window, the circle is drawn at the chosen radius and can be moved while being drawn. Click for animation (196K)


Click to view animationCircles may also be drawn tangent to any object using the Draw Tangent tool. The new circle may be positioned along the existing object, but can not be moved beyond its ends. If you hold down the Alt key when you start to draw, the new circle is snapped to the end of the existing object. Click for animation (151K)


Drawing Curves

Click to view animationThe simplest way to draw a curve is with the Draw Projecting Curve tool. The curve follows your cursor in length as you move about the drawing. You can reverse the direction of the curve by right-clicking the mouse while drawing, and change radius by holding the Shift key down. Click for animation (86K)


Click to view animation
Using the Draw Projecting Curve tool, you can draw a curve as a projection from an existing object. Before drawing, press the Alt key to indicate you want to project the curve from an object endpoint. If you hold down the Shift key, the radius of the curves changes as you move the mouse. Click for animation (118K)


Click to view animation
The Draw Transition Curve tool draws a Transition Curve and a new curve as a projection from an existing object. If the object is a line, the Transition Curve ranges from tangent to the final radius. You may change direction of the curve by right-clicking the mouse while drawing the new objects. Click for animation (103K)


Click to view animation
If you use the Draw Transition Curve tool from a curve, the Transition Curve ranges from radius of the selected curve, to the final radius. You may change direction of the curve by right-clicking the mouse while drawing the new objects. Click for animation (148K)


Click to view animationYou can also project a Transition Curve from another Transition Curve with the Draw Transition Curve tool. The new Transition Curve will pick up the radius of the existing curve on the end attached to it. As you move the mouse, the radius of the unattached end increases and decreases. Click for animation (106K)


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Last modified: September 29, 1999