Is it possible to change a 3D part back into a 2D sketch in SolidWorks?
Short Answer
Yes — in SolidWorks, you can turn 3D part geometry back into a 2D sketch by creating a sketch and using Convert Entities on model edges or planar faces. This is the most common professional method for rebuilding 2D sketch geometry from a part. Limitation: it only works cleanly on selectable edges or planar references.
What You Need to Know Before
Warning: Converted sketch geometry stays linked to the 3D model unless you manually break or replace it, so later model edits can unexpectedly change your sketch. Complex imported parts, splines, and non-planar faces also commonly produce incomplete or unusable sketch results.
How to Convert a 3D Part Back into a 2D Sketch
Command: Convert Entities
Shortcut: No default keyboard shortcut
Quick Steps:
- In the FeatureManager, select a planar face or plane, then start a sketch from the CommandManager: Sketch tab > Sketch.
- Select the edges, loop, or planar face boundary you want to capture, then click Sketch tab > Convert Entities.
- In the PropertyManager, confirm the selection and enable Select chain if you want connected edges converted automatically, then click the green check.
Variables & Settings
Key Setting: Select chain
Expert Setting: This option converts connected edges as one operation, which is faster for outer profiles and closed loops. Turn it off when you only need specific segments and want to avoid bringing in extra geometry.
Why it Fails
Cause 1 (Geometry): The part edges are not on a single plane, so the converted result cannot form a clean 2D sketch without projection or missing relations.
Cause 2 (layers/Locks): The sketch may be inactive, the plane/face was not selected first, or the part is opened in a state that prevents proper sketch editing, such as lightweight or problematic imported geometry.
Cause 3 (Command/Logic): Convert Entities does not reverse the original feature history; it only references visible edges, loops, or face boundaries, so you do not recover the original design intent or dimensions automatically.
Quick Fix & Best Practice
- Quick Fix: Create a new sketch on the correct planar face or reference plane, then run Convert Entities with Select chain enabled for the main profile.
- Manager’s Verdict: Use this method for extracting profiles, reusing outlines, and making manufacturing sketches. Avoid relying on it to fully reconstruct the original parametric sketch of a complex 3D model.
FAQ
Can I recover the original sketch from an extruded part in SolidWorks?
Only if the original sketch still exists in the feature tree.
Can I convert a non-planar surface into one 2D sketch?
No, not directly into a true single 2D sketch without projection compromises.
Does Convert Entities keep the sketch linked to the part?
Yes, by default the converted entities remain associatively linked.
.