Cut across bend around a rolled tube

[sebastien_marcoux]

I'm trying to do a usable and real flat pattern for a laser cut on this type of part and I'm not able to do a cut across bend or other wrap around face feature.

Do you know any method to do such a feature ?

[Curtis_Waguespack]

Hi sebastien_marcoux, 

If you start you part using the Contour Roll tool, you can then use the Unfold tool (not to be confused with Flat Pattern) and then create the Cut feature, and then use Refold tool. Attached is an example part to look at.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

[sebastien_marcoux]

Actually with this model I'm able to unfold it without any problems, but the shape that I need to trace once unfolded is not very intuitive for a simple miter cut.

[Curtis_Waguespack]

Hi sebastien_marcoux,

My applogies. I didn't understand that it was the miter that you were trying to work with. Can you explain your end goal here? I'm not following the need to "trace" the unfolded cut.

Thanks,

Curtis

[graemev]

If you're looking to make a wrap-around template for shop use, I do believe there's no easy way.  I'd gladly be proven wrong, however.

We have occasional need for wrap-arounds of this type in the shop for piping spools.  I created a parametric model that is driven by trunk pipe diameter and wall thickness, branch pipe diameter and thickness, angle of intersection (90 being a tee) and centerline offset (one may wish crowns or inverts to be tangent, for example).  The shapes generated are then plotted full scale on a roller bed plotter for use as a tracing template in the shop.  It's a bit of a grind to make the model, and the math isn't exactly fun, but the time and material saved from trial and error fit up makes it all worthwhile.

[Curtis_Waguespack · Accepted solution]

Hi sebastien_marcoux,

graemev's post helped me realize what you're after (I think). If it's the "beveled" edges in the flat pattern that are the issue, you can avoid these by using a surface/thicken workflow. Attached is another file that demonstrates this technique.

Note that I refolded the part using a different  stationary reference just to illustrate the use of the surface when the file is opened, but in most cases you'd use the same stationary reference to unfold and refold.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

[jeanchile]

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@graemev wrote:

... I do believe there's no easy way.  I'd gladly be proven wrong, however.

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I don't know... I thought the workflow that Dennis Jeffrey gave me over here a while back was pretty quick and elegant. After doing a couple hundred of them since I would say that I am very happy with the solution. I now have a paper template sheet metal rule (with the paper thickness and proper k dimension) that makes this process very efficient.

[sebastien_marcoux]

@Curtis_Waguespack: the end goal is to do a laser cut on sheet metal to roll the part and avoid the beveled edges in the flat pattern, as you stated in another reply.

I often do wrap around piping devellopements on paper to make a template, the beveled edges in this case is not a big issue, it gives an idea to the pipe fitter of the grinding implied in the job, but for the laser cut they arent desirable.

As I can see, the surface/thicken workflow is the good one to use in this case (thoses are features I dont really often work with 🙂 )

thank you for your help !