Contour Roll Cannot Use "Developed Length" Unfold Option for Simple Cylinders

[petestrycharske]

All,

Good afternoon!  I've run into a strange situation where I cannot utilize the "Developed Length" option for defining the size of my flat pattern, when creating a simple cylinder.  As soon as there is some other flange or bend, I can use all 4 options for defining the flat pattern.  However, for a simple cylinder, I'm forced to use the K-Factor.  Does anyone know why this is or if there's a way to use the "Developed Length" for a simple sheet metal cylinder?  Any advice would be great and I thank you in advance!  If you have any questions, please do not hesitate to contact me.  Hope all is well and have a most blessed day!

Peace,

Pete

[blair]

Can you post what you've done so far. Use the Rip command to create the small gap where the items will be joined/welded. 

As long as you have a gap, it can be 0.001 it will work.

https://help.autodesk.com/view/INVNTOR/2019/ENU/?guid=GUID-B30BDD38-9CF6-496E-9133-52A59CDCAEE6

[petestrycharske]

Here is a screencast of what I'm seeing on my side...

[blair]

I don't think they though of using the Rolled Contour for a simple cylinder or the programmers just didn't add the option. I would go with the create a solid cylinder and use the Rip command for a simple cylinder. 

I've notified the moderator to forward the post on to the IV team as a possible bug/issue and see what shakes out.

Blair

[johnsonshiue · Accepted solution]

Hi Pete and Blair,

This is actually an intended behavior. This is because, regardless of what unroll method is selected, the calculation is always done via "equivalent" K-factor. For example, the Unroll Length could determine the neutral layer, which dictates the K-factor.

For a pure cylinder, there is no need to have other methods. You can use K-factor to control the unroll length. With a given unroll length and bend angle, you can find the neutral radius. The percentage difference between the neutral radius and the inner bend radius (cylinder) is the K-factor to use.

Many thanks!

[petestrycharske]

@johnsonshiue,

Good afternoon!  Sorry that it has taken me so long to get back to this.  I understand what you're saying, but I think it's more of a convenience factor.  If a user wants to model the part accurately to develop a proper flat pattern, they would have to calculate the K-Factor themselves.  It's not impossible to do so, but it just takes time.  That's the reason, I would like to have the same option of using the developed length.  Hope this makes sense and have a most blessed night!

Peace,

Pete

[petestrycharske · Accepted solution]

Below is a method for calculating the required K-Factor.