sketch to DXF

[trampas]

is it possible to save a sketch as a DXF?

[easyw-fc]

is it possible to save a sketch as a DXF?

in Draft WB you can convert Sketch to Draft (command Draft to Sketch) and then export to Autodesk dxf

[NormandC]

Or you simply select the sketch itself and export it to Autodesk DXF.

It works.

[otto9F9otto]

But how well does "export to DXF work? I opened my drawing (created in sketcher) then selected the Draft workbench. Sure enough, export to DXF was there, so I did. Then, I opened the exported drawing with LibreCAD. I got the drawing, but the dimensions are missing. Darn.

My system specs:

OS: Linux Mint 18.3 Sylvia
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.13638 (Git)
Build type: None
Branch: master
Hash: 983f2472a871f8b808fccdf8fa8d05dd276c3fba
Python version: 2.7.12
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.2.0
Locale: English/UnitedStates (en_US)

[NormandC]

Sure enough, export to DXF was there, so I did. Then, I opened the exported drawing with LibreCAD. I got the drawing, but the dimensions are missing. Darn.

There are no dimensions in a Sketch. They are dimensional constraints. It's not the same thing. They are not exported because they are internal elements of the sketch that are not exposed outside of the sketch edit mode.

[otto9F9otto]

What you are implying, NormandC, is a difference in philosophy: Dimensions + tolerances are constraints, and constraints can include dimensions + tolerances and other information.

Is the initial 3-D printing focus of FreeCAD the reason, also, why tolerances are not accommodated? After all, with 3-D printing, you get what the printer provides: tolerances are not part of the input.

If I design a part that is not to be 3-D printed (the best tool for my widget is a NC lathe), then my efforts may be better spent on a 2-D CAD program such as LibreCAD, which works directly with DXF drawings (no export necessary) and accommodates tolerances. A local machine shop that may fabricate my part requested DXF format.

Are my statements, above, correct?

I still think it would be cool if FreeCAD constraints were exported as dimensions upon DXF export.

[NormandC]

Are my statements, above, correct?

Most aren't.

What you are implying, NormandC, is a difference in philosophy: Dimensions + tolerances are constraints

No, that's not correct. Dimensions are informative about existing geometry. Dimensional constraints affect the geometry. They are totally different concepts.

It is not the purpose of the solver-based Sketcher to produce dimensioned drawings. Its purpose is to precisely define 2D geometry that is then used in 3D operations.

Is the initial 3-D printing focus of FreeCAD the reason

Another erroneous statement. FreeCAD's focus is not 3D printing, and it actually predates the 3D printing craze. It started as a mechanical computer-aided design program but with the years it got a wider range of intended purposes like 3D printing, architecture modeling, FEM, CAM, etc.

The basics of a parametric 3D CAD programs like FreeCAD are

• Build 3D models using 2D profiles (produced by various means such as the Draft or Sketcher workbenches) and 3D tools found in various workbenches (Arch, Part, PartDesign)
• Create technical drawings with projected views of the 3D model in the Drawing workbench (v0.16) or the new TechDraw workbench that aims to replace Drawing (v0.17)
• Add dimensions to the projected scaled views in the drawing page. The Drawing wb doesn't have dimensioning capability and requires an external plug-in. TechDraw does include dimensioning tools, but as it's the very first iteration, some tools are missing and will be added later.
• Print the page or export it as SVG or DXF. TechDraw is missing DXF export at this time.

As for tolerances, I assume you're talking about dimensioning tolerances, because a 3D model does not have tolerances built-in. TechDraw does not support tolerancing at this time, possibly the Drawing Dimensioning add-on for the Drawing wb does.

[easyw-fc]

What you are implying, NormandC, is a difference in philosophy: Dimensions + tolerances are constraints, and constraints can include dimensions + tolerances and other information.

Is the initial 3-D printing focus of FreeCAD the reason, also, why tolerances are not accommodated?

https://forum.freecadweb.org/viewtopic.php?t=22072

[otto9F9otto]

Thanks for the clarification, NormandC. Also, for the extra information, easyw-fc.