# Sweep

#### amnon

##### New member
Hey.

Why is my sweep prifile not perpendicular to guide curve?

ImageShack - Image Hosting :: beznazwy1.jpg

What are the rules to create sweep with a different curves. Should curves be joined before sweep or shoul I create sweep piece by piece.

Respect
Amnon

#### MrCATIA

##### Super Moderator
The direction of the profile is defined by the SPINE curve, which probably is the guide curve in your example. Why it is not perpendicular is hard to tell from the attached image, but I think it should be perpendicular. Look at it from the top to check.

Is the profile sketch perpendicular to the guide?

What are the Rules? The guide curve should be a contiguous curve with good tangent continuity. It's easier if you join the curves first, and just make a single swept surface. If you can, Federate the Join.

#### amnon

##### New member
I joined 2 helixs with different pitch, so my curve is not tangent continuity in some places. I checked my sweep and unfortunately, the profile is not perpendicular to guide curve. I attached sweep widnow.

ImageShack - Image Hosting :: window1.jpg

I made this sweep piece by piece and than I joined them.

Respect
Amnon

#### MrCATIA

##### Super Moderator
Ammon, regarding the Perpendicular Profiles

When you make the Swept surface, use the option at the bottom of the panel, Position Profile, to realign the circle perpendiculat to the guide curve. Oncer you choose this option, click the Show Parameters button. At the very bottom, is another option to Anchor Elements On The Profile and you want to define the centerpoint of the circle as your anchor point. I think this will solve your problem.

Another way to do this is to make the profile perpendicular to begin with. Add a plane normal to a curve at the end of the centerline, and then make a sketch of the profile (or circle) in this normal plane. This way the profile also remains perpendicular to the centerline as it is swept (as long as the spine is the centerline).

#### MrCATIA

##### Super Moderator
Ammon, after looking at your attached screen shot and seeing how you have modeled the spring; I'd like to describe how I would do it.

Model half and symmetry to get the other side

Since the spring is symmetrical, model one side of the spring as a solid and mirror to get the other side. The symmetry would be at the bottom of the tree

Single centerline and Single solid

I would create the various portions of the centerline and join them together to create a single centerline (or half centerline). Then make a single Rib, or Swept surface.

Profile Sketch

Make sure the sketch plane is normal to the centerline.

Curvature Continutity

Where the two helixs start/stop, I would add a radius to provide a nice transistion. Trim back both helixes a couple millimeters, and use a Connect curve to add the radius. You can use this technique for any corner bend between curves.

(sorry for having the steps backwards)

#### amnon

##### New member
Thank's a lot MrCATIA, for so detailed description. I had difficulties with transistion between two helixs.
I have to check it out.

#### amnon

##### New member
Is it possible to calculate free length of the sweep or the guide curve?

Respect
Amnon