Helix command in AutoCAD – Create the helix

1. The way to call Helix command in AutoCAD.

Scroll down menu	Screen menu	Type command	Tool bar
View » Helix	Draw1 » Helix	Helix	Draw

Helix command is to create 2D, 3D helix.

Helix
Number of turns = 3 (Default number of turn equal 3).
Twist = CCW (Default twisted direction is counter-clockwise).

Specify center point of base: – Specify the center of base line.

Specify base radius or [Diameter] <1.0000>: – Enter value of base radius

Specify top radius or [Diameter] <1.0000>: – Enter top radius

Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <1.0000>: – Enter height of helix or press enter to enter default value or enter an option.

As default, base radius is set up equal 1, value of top radius always equals value of base radius, you can enter again top radius. Both base radius and top radius do not equal 0 at the same time.

2. The options with Helix command in AutoCAD

Base radius (top radius)
This option is to enter base radius (top radius) of helix. If radius of base circle equals radius of top circle, you will get the cylinder helix; if radius of top circle is deferent to radius of base circle, you will get the cone helix.

Helix
Number of turns = 3.0000 Twist = CCW
Specify center point of base: – Select O as the center of base line.
Specify base radius or [Diameter] <1.0000>: 50 – Enter base radius.
Specify top radius or [Diameter] <50>: – Enter top radius.
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <1.0000>: 120 – Enter height of helix.

Helix command in AutoCAD – Create the helix

Helix
Number of turns = 3.0000 Twist = CCW

Specify center point of base: – Select O as the center of base line.
Specify base radius or [Diameter] <50>: 50 – Enter base radius.
Specify top radius or [Diameter] <50>: 20 – Enter top radius.
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <120>: – Enter value of height of helix.

Note:
When you create the cone helix, if the height of helix axis is 0 you will get the flat helix.
Diameter (Base/Top)

This option is to enter diameter of base circle (or top circle) of helix. When you enter D instead of Diameter option, the following prompt line appears:

Specify diameter < >: – Enter diameter of bottom circle or top circle.

Axis Endpoint

Define the position of the end point of helix axis. The end point of helix axis can be put at any point in space. The end point of helix axis defines the height and direction of helix.

Helix
Number of turns = 3.0000 Twist = CCW
Specify center point of base: – Select O as the center of base line.
Specify base radius or [Diameter] <50>: 40 – Enter base radius
Specify top radius or [Diameter] <40>: – Enter top radius.

Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <120>: A
Specify axis end point: Press S as the end point of helix axis

Turns

Define number of turns of helix, default is 3 turns, this value is not over 500.

Helix
Number of turns = 3.0000 Twist = CCW
Specify center point of base: – Select O as the center of base line.
Specify base radius or [Diameter] <40>: 30 – Enter base radius
Specify top radius or [Diameter] <30>: – Enter top radius
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <100.0000>: T
Enter number of turns <3.0000>: 4 – Enter number of turns
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <120.0000>: 100 Enter height of helix.

Turn Height
Define the height of a helix that is twist step of helix. Number of turns will be automatically updated following to the determined height of helix. If number of turns is defined, you cannot enter the height of helix.
Helix
Number of turns = 3.0000 Twist = CCW
Specify center point of base: – Select O as the center of base line.
Specify base radius or [Diameter] <30>: 25 – Enter base radius
Specify top radius or [Diameter] <25>: – Enter top radius
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <100.0000>: H
Specify distance between turns <25>: 30 – Enter value of twist step
Specify helix height or [Axis endpoint/Turns/turn Height/tWist] <120.0000>: 90. Enter height of helix (picture 3.9)

tWist
Define the direction of helix following to clockwise (CW) – called left twist or counter-clockwise (CCW) – called right twist. Default is right twist (CCW). When you enter W instead of tWist option, the following prompt line appears: