How do I create a plane tangent to a cylinder?

[RyanRun]

I have a revolved part and I want a plane tangent to the outside diamter. How do I accomplish this? I want the plane linked to the diamter, so that it moves if the outer diameter is changed.

Thank you

 

[solid7]

One of the easiest ways (in my opinion) to do this, is to create a sketch on the top face of the cylinder. You project the outside (cylindrical) face onto the plance, keeping the history. It will be a Mark, or projected edge, colored yellow. From here, you can create your line tangent to this circlular projection. You should set the circluar projection to construction, and the line to non-construction geometry.

Pop out of the sketch, and create a line normal to the cylinder top, from either end of the line. Create plane through 2 lines, and select the items just created.

You can also create a cylindrical projection, and strike a line from the center, trimming in it with the circular projection at a given angle. From that, you can create a normal plane on the endpoint of the line created in the sketch. Again, circular arc is construciton geometry, the line is not...

Hope that helps.

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CAD design engineering services - Catia V4, Catia V5, and CAD Translation. Catia V5 resources - CATBlog.

 

[RyanRun]

...oh yeah, in addition to being tangent, it also must be parallel to an existing plane.

 

[solid7]

Add a parallel constraint, or a an angle of zero degrees, instead of the angle shown...

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CAD design engineering services - Catia V4, Catia V5, and CAD Translation. Catia V5 resources - CATBlog.

 

[5050t]

Use a simple relation to create an offset plane from center of part.

eg. Plane offset distance = DIA / 2

Your plane will always remain tangent regardless of the diameter you specify and remain parallel to an existing plane.

 

[jackk]

I like 5050's method, but here's another way:

First, isolate the plane. Then add two constraints: one to make it tangent to the cylinder face, and a second to make it parallel to the other, non-isolated plane.

 

[johnny5ng]

5050t's method is good, but only parellel to the existing plane.
I will do this:

1. Use sketch to create a circle and pad to a cylinder.
2. creat a point ON CURVE align on the cylinder curve(you choose Distance or Ratio of curve from the point definition window)
3. creat a plane TANGENT TO SURFACE (you choose the surface and the point you just created from the plane definition window)

Now, whatever you change the Diameter of the cylinder, the point and the plane will be changed at the same time when you UPDATE.

 

[johnny5ng]

http://2htts.com/CATBlog/media/common/cy1.JPG

http://2htts.com/CATBlog/media/common/cy2.JPG