.stl to .step

I'm using freecad to make and .step from a .stl. But everytime I try to ''convert'' it, the program freezes up and need the file fast. You could some one do it for me?? I will be forever in your debt ;).

4 Answers

Funny I converted the file which I could open but after conversion, the step was empty I tried in several cad programs but the results where the same.

A section view of a screenshot is attached.
The red arrow shows a hole. The blue arrows show undercuts and hollow areas.

These really need to be repaired in the modeling software before the STL is created.
Creating a STEP should be possible once these defects are eliminated.
Maybe you could fix it up and upload a new mesh?

I should also ask what the goal is of converting the file to a STEP format.

Are you looking to have this remodeled in a CAD system so it is made up of very clean surfaces and is suitable for say CNC machining?

Or are you looking to simply convert a mesh model into a NURBS surface and are able to deal with the typical disaster which results to the topology?

A screenshot of the resulting topology is attached from a mesh to nurbs conversion.

Converting a mesh format into a STEP file is possible as you can see in my previous post (topolology.png). But using that STEP file in a CNC machine is somewhat unlikely.

You can see from the image that there are hundreds of small individual faces making up the model. Programming around all of these faces is going to be difficult.
As mentioned earlier, there are also a number of defects in the mesh model which should be repaired prior to continuing on to the next step. Hollows in the model, detached bodies, rough patches, zero thickness, undercuts, overhangs...
Overall the model is pretty good, it could really use some additional work though.
I'd consider 3D printing this model before machining it.
Holding it down on CNC equipment, and repositioning it a dozen times to access non-machinable surfaces is going to be quite difficult and time consuming.
3D printing could have this model built rather quickly.

Two models are attached. One STL which has been repaired for 3D printing. The other a STEP file based on the repaired STL.

To machine this the part should be remade in a solid modeling program. It would likely take several hours, but the surfaces would be clean. There would still be the issue of how to secure and position the part though.