topic Untwisting a part in sheetmetal and DXF export in Inventor Forum

Untwisting a part in sheetmetal and DXF export

Sergeev-Ivan — Thu, 05 May 2022 15:14:37 GMT

Hello! For learning purposes I'm currently trying to recreate an outdoor children's American Eagle playground, similar to one they have in Denmark at DOKK1 (you can look it up online).

I've created a surface model of the bird and now I have several issues. I was trying to break surfaces into even looking planks and i could not automate this process due to my lack of VBA and iLogic skills, so I decided to stick with freeform shape modeling and "bend edge" function. I was going to use "thicken" function, but when i do this i don't get individual planks. So, unfortunately, I will have to thicken faces one by one and then make them separate parts by using "create components" feature. Maybe anyone knows a better way to do this?

Also, some of my planks are twisted and I though I would be able to convert them to sheetmetal and to kind of untwist them with nesting functions or something, but it doesn't let me, giving a blank error. I wanted to make them flat and to export to dxf.

Some planks, located at the main body, look flat, but it seems like they are not. I'm wondering is there an option to extract dxf from these planks? Can you give me a hint is there and option to flatten them in freeform modeler or by using something else. Or is there a way to export to dxf strait from a surface?

I have attached an .ipt file. Thank you in advance.

Re: Untwisting a part in sheetmetal and DXF export

johnsonshiue — Thu, 05 May 2022 21:56:54 GMT

Hi! I don't think Inventor Sheet Metal can create Flat pattern from this kind of geometry. First, the bend radius is zero. It has to be non-zero. Second, the Loft creates spline faces. In some special case, Flat Pattern may work. But, in general, it will fail. Third, Sheet Metal does not work with Freeform geometry. I believe you best bet is to use Unwrap to flatten the faces.

Many thanks!

Re: Untwisting a part in sheetmetal and DXF export

Sergeev-Ivan — Tue, 17 May 2022 12:25:42 GMT

I've been unwrapping them manually for some time already and thought that may be there is a way to somehow use sheetmetal tools and addons for work automation. Very well then, will continue as it is. Thanks.

Re: Untwisting a part in sheetmetal and DXF export

cadman777 — Tue, 17 May 2022 12:43:56 GMT

That sculpture is lovely!

This looks like a perfect project to do in Rhino3d.

I don't have Inventor 2023, so can't compare results.

But if Walt could contribute (he has Rhino3d), I bet he can compare a flat pattern made in Rhino3d vs. Inventor's Unwrap. I also believe that making this would be much easier in Rhino3d.

If you can export this entire surface model as a STEP or IGES, I'll try to flatten it in Rhino and share the results.