Trim/L,New,Arc,External
Trim/Extend Line to Arc (External Tangent)
Trims or extends a line endpoint to meet an arc with external tangency. Creates a smooth external tangent connection between the line and arc.
What It Does
The Trim/L,New,Arc,External operator trims or extends a line endpoint to create an external tangent connection with an arc. The line endpoint is moved to the tangent point on the arc, and a connecting arc of radius R is created between them.
Syntax
Trim/Line/Arc, L0, A0, R, Start|End
Quick Input
L: 0
A: 0
R: 5.0
N: 64
End: Start End
Direction Selector
| Selector | Meaning |
|---|---|
Start | Trim/extend the start endpoint of the line |
End | Trim/extend the end endpoint of the line |
Worked Examples
Setup:
L0 = Horizontal line from (0,0) to (60,0)
A0 = Arc: centre(100,30), radius 20, 180 to 270 CCW
R = 15 [connecting arc radius]
Trim/Line/Arc, L0, A0, R=15, End
→ L0 end trimmed/extended to tangent point
→ New connecting arc created between L0 end and A0
with external tangency and radius 15
Analytic Rule
Find external tangent connection between line L and arc A.
Compute connecting arc of radius R tangent to both.
Move line endpoint to tangent point on connecting arc.
Create connecting arc between line and target arc.
Result: Smooth external tangent connection.
FAQ
What is the difference between external and internal?
External (this operator): the connecting arc touches the outside of the target arc. Internal (Trim/Line/Arc/Internal): the connecting arc curves inward, creating an internal tangent connection.
When would I use this?
Use when you need to smoothly connect a line endpoint to an arc with a blending arc — common in profile construction for CNC machining.