Cutting sheet metal tube with a surface

[Kanon]

Hi All

I am trying to trim a lofted sheet metal half cylinder (in grey) with the blue surface. Is this possible with Alibre Expert?

 

[DavidJ]

It doesn't look as though that surface goes all the way through the part - but that might just be the way the view is oriented.

Is that an imported surface, or one generated in AD ?

 

[Kanon]

Its is a Alibre part. I want to trim off the exposed grey sheet metal to be flush with green and blue. Apologies it not a surface, but the surface of the part green and blue. The blue was just highlighted when selected

 

[DavidJ]

Perhaps use a Boolean...

 

[Kanon]

Thanks I will try that!

 

[bigseb]

Like David says using boolean is probably the best way in your case. You may need to trim with DE. There is also a way to do this using surfaces. However Alibre decided to make this route non-associative (another thing I have yet to see fixed).

 

[Kanon]

Noted, thanks bigseb. Remind me, what is DE?

 

[Kanon]

I used boolean intersect as I wanted the grey sheet metal part cut not the green part. Unfortunately it has changed from a sheet metal to a solid part. I tried changing it to a a sheet metal part but had no success. To get the grey sheet metal part (shown above) it needs to be flattened, printed as a template, then profile cut and rolled to the shape shown. Any suggestions?

 

[Kanon]

I also tried using the sheet metal half cylinder and tried to boolean subtract a part but I could not find the boolean tool in sheet metal.

 

[HaroldL]

If you know the radius of the curve you are trying to match can you not just cut a lofted flange to the required curvature? It should still flatten for you.

 

[Kanon]

No. Unfortunately the radius of the curve to cut varies.

 

[DavidJ]

Another option is to 'Edit Here' the sheet metal part in the assembly, then use Project to Sketch from relevant edges of the green part to help create a sketch to use in a through all cut.

 

[Kanon]

I tried that, unfortunately the cut follows a large radius not a straight cut. You have to use a sweep cut or revolve cut but this not an option in sheet metal.

 

[DavidJ]

You can enable the Part Features (including Booleans) in SMP - but be aware that use of them can in some cases prevent flat patterning.

 

[bigseb]

Noted, thanks bigseb. Remind me, what is DE?

DE = direct editing.

 

[HaroldL]

Note that with sheet metal the final part may not fit perfectly because any cut is normal to the sheet metal surface.
If the part you are working on is not proprietary could you upload it so someone else could take a look to see what other solution may work? If you can't upload the model in question maybe something similar.

 

[Kanon]

Hi Harold and DavidJ. Ok, herewith attached is a similar assembly. Thanks for you help!

 

[Lew_Merrick]

Hi Harold and DavidJ. Ok, herewith attached is a similar assembly. Thanks for you help!

Hi Kanon -- It would be best if: (1) You name the Assy something more "descriptive" than Alibre. (2) Create an "AD_PKG" (Package) file from the Assembly and upload it. -- Lew

 

[idslk]

Hello Kanon,
i have saved your three files to "disk" and after that, i opened the assembly (for those, who are only knowing packages...)
But more or less... I've been able to do the boolean subtract at your sheetmetal part:

but after unbending it, the curved cut faces magically went partial away...

this would not be an acceptable result for me...
maybe somebody can do this better, sorry.
Regards
Stefan

 

[HaroldL]

but after unbending it, the curved cut faces magically went partial away...

That's because ALL cuts in sheet metal are normal to the surface. I think they show in the Boolean because the end surfaces are adopted in the Boolean operation. An actual sheet metal part would need some machining to match the curved end faces where the usual process would be a normal cut.