18 Replies Latest reply on Jul 15, 2014 5:41 PM by freaky lion

# How to draw a coil... not spring or helix

I need to draw a coil.... similiar to a roll of paper towel.  I tried a string of tangent arcs... gets messy.

• ###### Re: How to draw a coil... not spring or helix

look up "spiral" in the help, or in this forum.

• ###### Re: How to draw a coil... not spring or helix

this does not work for because a pitch of 0 will not work.  i need the coil to be 2d.

• ###### Re: How to draw a coil... not spring or helix

A zero pitch would be a cirle, you need a pitch to give you a space between the lines.

• ###### Re: How to draw a coil... not spring or helix

It should work if you set it to spiral.

• ###### Re: How to draw a coil... not spring or helix

thanks guys

• ###### Re: How to draw a coil... not spring or helix

I realized i need to rephrase my question. Need a variable pitch helix with 0 height.

• ###### Re: How to draw a coil... not spring or helix

This is the only way I can think of getting a variable pitch.

• ###### Re: How to draw a coil... not spring or helix

Excellent...This will work.

• ###### Re: How to draw a coil... not spring or helix

Hi,

I'm wondering if it’s possible to draw an elliptical spiral. I know how to make a spiral out of circle. But if I try to use an ellipse Solidworks doesn’t want to grab it.

Thank you and best regards.

• ###### Re: How to draw a coil... not spring or helix

Freaky

I would make the "round" coil then scale it in one dimension.

Dwight

• ###### Re: How to draw a coil... not spring or helix

I'm not so familiar with SW. Is it possible to attach solidworks model where you have done this?

Thank you.

• ###### Re: How to draw a coil... not spring or helix

Use an equation driven curve in a 3d sketch.

• ###### Re: How to draw a coil... not spring or helix

Can you please tell me how the equation will look like?

Thank you.

• ###### Re: How to draw a coil... not spring or helix

X = r1*cos(2*pi*p*t)

Y = r2*sin(2*pi*p*t)

Z = t

Where r1 is one axis of the elipse, r2 is the other axis of the elipse, and p is the pitch of your helix.

• ###### Re: How to draw a coil... not spring or helix

In my case pitch should be 0. I need spiral and not helix. Will this work?

• ###### Re: How to draw a coil... not spring or helix

No, then you'd want something like

X = p1*t*r1*cos(2*pi*p2*t)

Y = p1*t*r2*sin(2*pi*p2*t)

in a 2d sketch.

Sorry for the misunderstanding.

• ###### Re: How to draw a coil... not spring or helix

Thank you. And what is p1, p2 and t?