Unroll a tube 1

[EngJW]

I have a tube with several holes drilled in it. Now the factory wants to make it out of sheet metal and roll it instead of buying tube. I tried to make a pattern by going back to the first sketch and keeping just the od. I put a small gap in it and then converted it to a base flange. Everything looks ok but the part cannot be flattened. Apparently SW wants flat surface for reference and does not recognize the round surface.

Is this even possible to do? I could just make a sketch and calculate the flattened dimensions if not.

 

[CorBlimeyLimey]

You should be able to pick an edge face ... ie; one of the faces created by the gap.


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[SBaugh]

See the help on Conical sheet metal

Regards,

Scott Baugh, CSWP
3DVision Technologies

http://www.3dvisiontech.com

http://www.scottjbaugh.com

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[ctopher]

also do a search in this forum. I think it has been covered before.

Chris
Sr. Mechanical Designer, CAD
SolidWorks 05 SP1.1 / PDMWorks 05
ctopher's home site

 

[MElam]

If it was created with a base-flange with a gap in the sketch, it should flatten. There seems to be something else going on.

How did you "convert" to a base-flange from what it was? There may be an issue with the editing process. Does it work if the part is recreated from scratch?

 

[EngJW]

I used the procedure for cylindrical sheet metal, which is similar to the conical one mentioned. If it is supposed to work, then I am probably doing something wrong with the sketch.

The sketch is just a circle with a gap in it. The diameter and the gap size are specified. The base flange feature calls for a bend radius so maybe that is the source of the problem. If the diameter of the part is specified, I'm not sure what they mean by bend radius.

 

[CorBlimeyLimey]

1) Make sure the gap is large enough to not be closed up by adding the material thickness.

2) The bend radius (usually 1 x material thickness, depending on the fab shop) would be used if you added an Edge flange (or similar) to the gap edges, as though the material had actually been formed on a press. It does not refer to the radius you are using to create the split tube, that can be whatever you specify.


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[rocky640]

Does the gap you created leave a surface that is parallel to a plane? If not it will not flatten. The way we do this is to create a round extruded feature and then in the next step creat a cut the is a wedge. The wedge is only 0.01 degree and one side of the wedge must me parallel to the vertical or horizontal plane. Then we can use the Insert Bends command to change it to sheet metal. This command will want you to choose one of the edges that doesn't move when it is unfolded. Hope this might help.

 

[CorBlimeyLimey]

If you use the Sheet Metal function, that happens automatically.


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[smcadman]

Try adding the holes while in the flat pattern. Take a look at Item #11 for an example:

http://www.sheetmetaldesign.com/Cad-SolidWorks/index.htm

Flores

 

[huey1d]

I used the "Creating Sheet Metal Parts with Cylindrical Faces" and added the holes (over 200) in the flat. The file is very large and slow to flatten and form (re-roll).