Inventor 2024: How to extrude a boss from the curved surface of a cylinder so that the top of the boss is concentric to the cylinder?

[dfitzgerald2002]

I am trying to create a boss that extends from the curved surface of a cylindrical part. I haven't found anything in this forum or on YouTube that matches what I'm trying to do.

I have spared everyone from 1000 words by attaching a picture of what I am trying to achieve. The shaded (hashed) portion shows the desired boss. Any suggestions, please?

[JDMather]

@dfitzgerald2002 

Attach the *.ipt file of your attempt here.

Two Circles.

One Rectangle.

Two mid plane Extrusions.

[dfitzgerald2002]

The circles are drawn from the top view in 2D? One circle has the circumference of the cylinder, the other circle has the circumference of the cylinder plus the depth of the extrusion?
Can these circles be created as working drawings to avoid confusion?

The rectangle can be drawn in 3D on the cylinder? Or, in 2D and projected to the cylinder surface?
To assure correct placement & orientation, can/should I constrain the extrusions along an axis?

[JDMather]

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@dfitzgerald2002 wrote:

Can these circles be created as working drawings to avoid confusion?

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I do not know what this means?

Example 1

Example 2

@dfitzgerald2002 

As a beginner you should ALWAYS attach your attempt here.

See my two attempts attached below.

[SBix26]

See my part attached to your other topic...

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Sam B

Inventor Pro 2024 | Windows 10 Home 22H2

[dfitzgerald2002]

quick reply..... Sorry, they are called construction lines. I mistakenly called them working lines.

I think that I'm picking up on your methods, JD..... I suppose that you give brief responses in order to give the student (e.g., me) a hint, but not step-by-step instructions, in order to make them try on their own before asking questions. Very interesting! I'll try on my own before asking follow-up questions.

However, I think my question about using construction lines is reasonable. Can they be used to create the circles to which you refer because they aren't part of any feature?

[JDMather]

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@dfitzgerald2002 wrote:
 I suppose that you give brief responses…

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@dfitzgerald2002 
Did you examine the files that I attached?

Do you observe any Construction Lines in my sketch in Example 1?

The files contain all of the information needed to reproduce my technique.

I tend to give exceptionally brief responses when the poster doesn’t Attach their file showing what they have attempted on their own.

[johnsonshiue]

Hi JD,

I believe the OP is looking for offset Extrude. It is also available in Inventor, just not that apparent in this case. Your Example2 can illustrate the workflow. Simply edit Extrusion3 -> click on From selection -> select the cylindrical face 

and give a distance. After that, just repeat the process for the other side.

Many thanks!

[IgorMir]

Seems like fairly trivial task to me. Here is a part in IV2020 format.

Cheers,

Igor.

[dfitzgerald2002]

JD,

I understand the concept of how you obtained the desired extrusion. Drawing the circles is straightforward. However, I don't understand how you located the rectangle. When I click on "Start 2D Sketch" to draw the rectangle on my part, my file opens to the top view and it shows the X and Z axes. When I click on the (top right) cube to see the front view (so that I can draw the rectangle), all of the axes disappear from the drawing so I don't know how to draw my lines such that the center of the extrusion is aligned with the center of the part.

Is there some way to make the lines of my X, Y, and Z axes always visible such that I have a reference point from which to drawl and/or measure my lines for correct location and orientation?

[kacper.suchomski]

One video, 20 potential combinations of different tools and methods.

[JDMather]

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@dfitzgerald2002 wrote:

When I click on "Start 2D Sketch"...

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What if you select the desired sketch plane BEFORE clicking Start 2D Sketch?

[dfitzgerald2002]

J.D.,

I am at wit's end. I still don't have a solution. I also need to add one more descriptive constraint of my own.... The part is designed to be cylindrical and concentric. The end plane of the extrusion needs to be arc-shaped (w/ same radius as a circle of the same radius), yet the sides of the extrusion need to be perpendicular to the drawing plane.

Attached is the file and the work that I have done so far. I don't understand how you can tell what I've tried, so I've added my description:

- I've tried extruding from the drawing plane but I can't get the end plane of the extrusion to have a radius.

- I tried extruding from the face of the cylinder (directly under the extrusion feature) by picking the starting point on the cylinder face and giving a depth of extrusion, but the end plane of the extrusion had the same radius as the cylinder from which it started.

- I tried to make a circle on the XZ plane (in order to define the radius of the extrusion's end plane), from the TOP view, but the program wouldn't even allow me to make a simple circle.

Here's another problem I ran into...

- The feature can't be extruded in both directions. Otherwise, one of the features will have a mirror image of what it is supposed to be. There may be an easier way, but I was forced to draw the feature two times. The problem was: when I rotated the part to draw on the opposing face I could see the lines for the feature from the opposing face. Once I draw lines on top of other lines, I am unable to differentiate and/or select either set of lines.

Please help,

David

1) I tried extruding from the drawing plane but the geometry of the end of the extrusion is not correct

[dfitzgerald2002]

Forgot to attach file....

[dfitzgerald2002]

I'm sorry. I should have clarified my desired outcome a little better...

Your solution will create an extrusion. However, the endplane of the extrusion will have the same radius of the cylinder face from which it started. I didn't says this previously, but I need the end plane of the extrusion needs to have an arc shape with a radius equal to a circle with a centerpoint at the center of the part and a radius that ends on the same plane as the extrusion AND the sides of the extrusion need to be perpendicular to the drawing plane from which they extend.

[JDMather]

@dfitzgerald2002 

Let's return to the foundation...

zoom in here, what do you observe?

[JDMather]

@dfitzgerald2002 

Examine my Sketch1 Attached.

[JDMather]

@dfitzgerald2002 

I don't see anything in your Sketch2?

[JDMather]

@dfitzgerald2002 

The location of your Sketch3 is not fully defined?

[JDMather]

If I Project Geometry that edge and then add a Coincident to the Midpoints it is fully defined.