topic Re: Scale STL File in Inventor Forum

Scale STL File

eric.frissell26WKQ — Wed, 12 Jan 2022 18:19:30 GMT

Hi, I apologize if this has been asked before but I'm not entirely familiar with 3d printing or Inventor's options to handle file exports. I have an Inventor assembly I would like 3D printed but at about 1:15 scale from the full assembly. Is there a way to customize the scaling when exporting?

Secondly would there be a way to set a global minimum thickness on the exported STL file? Or that the surface geometry is exported and it's recognized as a solid part?

Re: Scale STL File

mcgyvr — Wed, 12 Jan 2022 18:51:01 GMT

No option (other than unit changes) to scale during export but you would just Derive and Scale in Inventor or scale in your 3d printer slicer software.

Now I'll answer the rest but I have a feeling there is some specific reason you are asking these questions and having more detail might allow better/more useful answers..

So..

No way to specify min thickness on the exported file.. It will match your 3d model and you would just control thickness.

Surface geometry is exported and you would turn its visibility off in Inventor to prevent that.

Re: Scale STL File

eric.frissell26WKQ — Wed, 12 Jan 2022 19:13:55 GMT

Hi Mcgyver, thanks for the reply. I don't have a 3d printer (or software) and am going through a 3rd party to get the model produced and what they've told me is that I don't have enough wall thickness as the minimum is .031". Part of the model is a tank made from steel that's .135" so scaling past 1:4 we I end up having wall thickness issues because the middle of the tank is hollow. If it's easier to export the model with no hollow areas that'd work for me as well. Can shrinkwrap accomplish this? If so I imagine the process would look like

Shrinkwrap -> create derived part/assembly -> scale derived part/assembly -> export derived part/assembly as STL ?

Re: Scale STL File

mcgyvr — Wed, 12 Jan 2022 20:39:29 GMT

Without knowing more I'd still simply derive and scale as discussed then use delete face, create a new solid to fill or use thicken,etc... any areas that are problematic.

Shrinkwrap can likely also accomplish the task but is likely to "easy button" to work when you need more selectability of what voids its effecting.

Here a "soup can" was derived into a new part and scaled then I used delete face to essentially fill the can and remove the interior void

and with the Delete Face feature suppressed to show original..

Re: Scale STL File

eric.frissell26WKQ — Thu, 13 Jan 2022 15:28:23 GMT

I see what you're saying and I suppose that is a viable method but given the complexity of the assembly individually thickening each face would be really time consuming, but scaling could be the right idea.

I guess to try and re-iterate the problem we have a large machine made up primarily of sheet metal and welded structural metal (tube/angle, etc...) which we're trying to create a 3d file of to use at a trade show. Currently we're looking to scale the file to 1:15 size and our supplier recommends a minimum wall thickness of any part of the printed file to be at least .031". Given that we're exporting at 1:15 that means that anything modeled under .465" thick will need to be thickened. The assembly is roughly 1,000 components and most of the assembly is sheet metal which is bolted to structural. There'd be roughly 100~200 thicken operations to ensure that everything is thickened to the point where it's a solid object, or hundreds more to make it a hollow object but with the minimum wall thickness.

Most of my understanding of what is possible comes from over a decade in SolidWorks and praying that Inventor has the same capability, so in this case I'd like to export the file as a single solid body, scale it, then create the STL file. This should be the easiest method but Inventor seems to be pushing back.

I think this should add a bit of clarification to what I'm trying to do

Re: Scale STL File

swalton — Thu, 13 Jan 2022 16:38:16 GMT

I design 60' long machines. I have tried to create 3d printed scale models for trade shows and demonstrations.

I have not found a useful workflow for simply exporting a .stp file of the full scale model and trying to shrink it to make a 3d print. I always run into the thickness issue you have found. 0.250" plate shrinks to 0.005" thick when I go from a 60' full scale model to a 1' demo model.

The only solution I have found is to manually create a brand new scale model that understands the manufacturing constraints of 3d printing.

I'd love an easy button, but I haven't found it.

Re: Scale STL File

mcgyvr — Thu, 13 Jan 2022 17:14:15 GMT

@eric.frissell26WKQ wrote:

Most of my understanding of what is possible comes from over a decade in SolidWorks

@eric.frissell26WKQ So what does solidworks do differently? Does it have a function to somehow maintain a min thickness of a scaled model?

I tried to search in the Solidworks help/forums and didn't come across such a function

Re: Scale STL File

eric.frissell26WKQ — Fri, 14 Jan 2022 18:57:34 GMT

Hi Mcgyver, it doesn't have an ability to maintain a scaled thickness however I think I remember it being 'easy' to export a part/assembly to a step file that was either completely filled in or as a surface which was then able to be filled in later. If I had a copy of the program I could try to figure it out but it's entirely possible I'm mis-remembering or mixing up things I had figured out or problems I encountered in the program. At this point I am just going to go ahead and use thicken and try to get a completely solid model, thanks for the help

Re: Scale STL File

mcgyvr — Fri, 14 Jan 2022 19:30:19 GMT

@eric.frissell26WKQ Please try "Delete Face" too.. I "think" that will be faster than thicken for you..

and yes please try "Simplify"... You can use its "Remove Features" function to remove pockets,etc... and see how that works for you.. Then simply save as stl..

I suspect though its "automatic selection" is too generic and selects too much and its too much work to preserve features you do want

Re: Scale STL File

johnsonshiue — Tue, 08 Feb 2022 20:33:29 GMT

Hi Eric,

Inventor has limited mesh handling workflows. I suggest you look into Fusion 360 where there is a dedicated Mesh Design environment with many workflows.

Many thanks!