Creating geometry on a curved surfaces

[carbonated]

I have a cyclindrical sheet metal part (.1 thick) that has a series (or a pattern) of cutouts that are radial to the CL of the cylinder. The cutouts are made on a flat metal sheet and then folded to the correct OD before butt welding the ends together.

If I create a workplane on the OD, then create a sketch of the cutout geometry and do an extrude cut, the geometry of the part will not be perfect as the WP is flat and does not take into effect the curve of the OD.

Is there a way to make the cutout geometry on a flat pattern and then fold the piece to the correct OD? This would make the part correct and is how the part is manufactured.

Thanks in advanced!

[JDMather]

Can you post the file?

Create a sacrificial planar face.
Start a new sketch on the face and Project Flat Pattern.
Create you sketch geometry.
Cut Across Bend.
Cut the sacrificial geometry.

Probably a few other ways as well.

[Anonymous]

il giorno 08/01/2008 16.07 carbonated ha scritto:

> I have a cyclindrical sheet metal part (.1 thick) that has a series
> (or a pattern) of cutouts that are radial to the CL of the
> cylinder. The cutouts are made on a flat metal sheet and then
> folded to the correct OD before butt welding the ends together.

Why not to cut before folding, then (see attachment, IV11)?


M.

[carbonated]

I have no idea what you are talking about (sacrificial planar face). See the attached file. Please dumb your answer down more if you can:)
Thanks!

[JDMather]

Can you zip and attach the ipt?

[carbonated]

This is a simple version. The version I ma working on has a more complex cutout.

Thanks in advance!

[Anonymous]

il giorno 10/01/2008 14.19 carbonated ha scritto:

> This is a simple version. The version I ma working on has a more
> complex cutout.


This is the workflow I'd follow.

M.

[carbonated]

Thanks Marco but your method is too complex for me to understand.

[JDMather]

>This is a simple version.

Since you didn't post the actual dimensions I didn't take the time to build in the parameters as a function of the geometry.

The flat patttern takes several minutes to calculate so be patient.

What release of Inventor did you say you were using?

[carbonated]

JD,

I use V11 so I cannot open your file. Thanks anyway!

[JDMather]

>I use V11

Didn't you think that was important?

[Anonymous]

il giorno 10/01/2008 15.39 carbonated ha scritto:

> Thanks Marco but your method is too complex for me to understand.

I worked on a surface instead of a solid, and on a sector instead of
on the whole cylinder.

I cut out the shape of the surface, and thickened the resulting
sector, so that the cut border are radial everywhere.

But I'm thinking that it is not exactly what you needed (sketch the
cut shape in a plane), so I did as in attachment.

I extruded the section, then I cut the shape, and then I bended it to
get a circular sector, to be serialized around the axis.

M.

[carbonated]

I don't get what you are saying.

[carbonated]

Awesome, I can almost understand it:>)

When you folded the initial extrusion, how did you get it to change to a arc (diameter)? I would think after you folded it, it would be at an angle, not an arc.

Thanks!

[Anonymous]

Look at the first Feature & Sketch, it's a line that's revolved as a
surface.

Mike

wrote in message news:5817173@discussion.autodesk.com...
Awesome, I can almost understand it:>)

When you folded the initial extrusion, how did you get it to change to a arc
(diameter)? I would think after you folded it, it would be at an angle, not
an arc.

Thanks!

[Anonymous]

il giorno 10/01/2008 17.56 carbonated ha scritto:

> When you folded the initial extrusion, how did you get it to change to a arc
(diameter)? I would think after you folded it, it would be at an
angle, not an arc.

Are you talking about B-0101671_SC_CAGE_03?
You have just to properly set the fillet radius. Have a look at folds
parameters.

M.

[carbonated]

Why can't I fold this part?

I wan't a radius of 1.720.

Thanks!

[Anonymous]

il giorno 11/01/2008 14.18 carbonated ha scritto:

> Why can't I fold this part?

Because the line in sketch4 is not properly constrained to the border
of the solid.

M.

[carbonated]

I now have the line constrained but when I try to apply a circular pattern no worky.

Sorry to bug you about this but I need to learn it as I will be doing many more.

Thanks.

[Anonymous]

il giorno 11/01/2008 15.28 carbonated ha scritto:

> I now have the line constrained but when I try to apply a circular
> pattern no worky.

I created a new work axis, that is the axis of the arc. It should
coincide with X axis, but if you use X axis for the circular pattern
it works bad.

You also should pay attention to properly constrain sketches to
improve precision.

Have a look at the attachment.

M.