Converting entities and intersection curves in Solidworks - Step-by-Step Guide

Introduction

This feature helps you create new sketch lines by copying edges or curves from existing 3D models. It solves the problem of manually tracing complex shapes by automatically projecting those shapes onto your sketch plane.

When you want to reuse the edge of a 3D part as a sketch line for a new feature

When you need to create a sketch that matches the intersection curve between two surfaces

When you want to quickly create reference geometry from existing model edges

When designing parts that must align exactly with existing features

When you want to avoid redrawing complex curves manually

Steps

Step 1: Open

- SolidWorks and open the part file with the geometry you want to use

The part model appears on screen

Step 2: Create

- a new sketch on the desired plane or face

The sketch environment opens with a blank sketch on the selected plane

Step 3: Click

- the 'Convert Entities' button on the Sketch tab of the CommandManager

The tool is activated and ready to select edges

Step 4: Select

- the edges, faces, or curves on the 3D model you want to convert

The selected edges highlight and preview lines appear in the sketch

Step 5: Confirm

- by clicking the green checkmark or pressing Enter

The selected edges are projected as sketch entities on the sketch plane

Step 6: For intersection curves, click

- 'Intersection Curve' on the Sketch tab, then select the two surfaces or faces

The curve where the two surfaces intersect is projected onto the sketch plane

Step 7: Finish

- the sketch by clicking 'Exit Sketch'

The sketch with converted entities or intersection curves is saved and ready for further use

Before vs After

Before

A blank sketch on a plane with no lines or curves

After

The sketch shows lines exactly matching the edges or intersection curves from the 3D model

Settings Reference

Convert Entities

📍 Sketch tab on the CommandManager

Select which model geometry to project into the sketch

Default: Edges

Intersection Curve

📍 Sketch tab on the CommandManager

Create a sketch curve from the intersection of two surfaces

Default: None

Entities to Convert

📍 Selection during Convert Entities command

Choose how much geometry to convert at once

Default: Single edge

Common Mistakes

Trying to convert entities on a sketch plane that does not intersect the model edges

No edges will project because the sketch plane is not aligned with the model geometry

Select a sketch plane or face that intersects the edges or surfaces you want to convert

Selecting faces instead of edges when using Convert Entities

Faces do not convert directly; only their edges project

Select the edges of the face or use Intersection Curve for surface intersections

Summary

Convert Entities projects existing model edges or curves onto a sketch plane to reuse geometry.

Intersection Curve creates sketch lines where two surfaces meet, helping capture complex shapes.

Always choose a sketch plane that intersects the geometry you want to convert for successful projection.

Practice

1. What is the main purpose of the Convert Entities tool in SolidWorks?

easy

A. To delete unwanted sketch lines automatically

B. To create new 3D surfaces from sketches

C. To project existing edges onto the current sketch plane

D. To merge two separate sketches into one

Solution

1. Step 1: Understand the function of Convert Entities

   The Convert Entities tool projects edges or faces from existing geometry onto the active sketch plane.

2. Step 2: Compare options with this function

   Only To project existing edges onto the current sketch plane describes projecting existing edges onto the sketch plane, matching the tool's purpose.

3. Final Answer:

   To project existing edges onto the current sketch plane -> Option C

4. Quick Check:

   Convert Entities = Project edges [OK]

Hint: Convert Entities projects edges onto sketches quickly [OK]

Common Mistakes:

• Confusing Convert Entities with creating new surfaces
• Thinking it merges sketches
• Assuming it deletes sketch lines

2. Which of the following is the correct way to use the Intersection Curve tool in SolidWorks?

easy

A. Select two intersecting surfaces to create sketch lines where they meet

B. Select a single edge to convert it into a 3D curve

C. Draw freehand lines that snap to existing edges

D. Automatically fill closed sketch profiles

Solution

1. Step 1: Identify the purpose of Intersection Curve

   Intersection Curve creates sketch lines from the intersection of two or more surfaces.

2. Step 2: Match the correct usage

   Select two intersecting surfaces to create sketch lines where they meet correctly states selecting two intersecting surfaces to generate sketch lines at their intersection.

3. Final Answer:

   Select two intersecting surfaces to create sketch lines where they meet -> Option A

4. Quick Check:

   Intersection Curve = Lines from surface intersections [OK]

Hint: Use Intersection Curve on surfaces, not edges [OK]

Common Mistakes:

• Trying to use Intersection Curve on a single edge
• Confusing it with freehand drawing
• Assuming it fills sketches automatically

3. Given a model with two intersecting planes, what will happen if you use Intersection Curve on these planes?

medium

A. The sketch will be deleted automatically

B. The planes will merge into a single surface

C. Nothing will happen because planes cannot intersect

D. A sketch line will be created along the intersection line of the two planes

Solution

1. Step 1: Understand intersection of planes

   Two planes intersect along a line if they are not parallel.

2. Step 2: Apply Intersection Curve tool

   Using Intersection Curve on these planes creates a sketch line along their intersection.

3. Final Answer:

   A sketch line will be created along the intersection line of the two planes -> Option D

4. Quick Check:

   Intersection Curve on planes = sketch line [OK]

Hint: Intersection Curve creates lines where surfaces meet [OK]

Common Mistakes:

• Thinking planes cannot intersect
• Expecting surfaces to merge
• Assuming no output is created

4. You tried to use Convert Entities on a face but no sketch lines appeared. What is the most likely reason?

medium

A. The sketch plane is not parallel or intersecting the selected face

B. You selected multiple faces instead of one

C. Convert Entities only works on edges, not faces

D. The model is in 3D view mode

Solution

1. Step 1: Check sketch plane relation to face

   Convert Entities projects edges onto the active sketch plane; if the plane does not intersect or align with the face, no projection occurs.

2. Step 2: Evaluate other options

   The sketch plane is not parallel or intersecting the selected face correctly identifies the plane-face relation as the cause; other options are incorrect because Convert Entities works on edges of faces and multiple faces can be selected.

3. Final Answer:

   The sketch plane is not parallel or intersecting the selected face -> Option A

4. Quick Check:

   Sketch plane must intersect face for Convert Entities [OK]

Hint: Ensure sketch plane crosses face before converting entities [OK]

Common Mistakes:

• Assuming Convert Entities works without plane intersection
• Believing it only works on edges, not faces
• Ignoring sketch plane orientation

5. You want to create a sketch that exactly follows the edges where a cylinder intersects a plane at an angle. Which combination of tools should you use?

hard

A. Use Convert Entities directly on the cylinder edges only

B. Use Intersection Curve to create the intersection lines, then Convert Entities to project them onto your sketch plane

C. Draw the intersection manually using the line tool

D. Use the Extrude tool to create the intersection

Solution

1. Step 1: Identify the intersection between cylinder and plane

   The intersection between a cylinder and an angled plane is a curve, not a simple edge.

2. Step 2: Use Intersection Curve to create sketch lines

   Intersection Curve generates the exact intersection lines between the cylinder surface and the plane.

3. Step 3: Use Convert Entities to project onto sketch plane

   After creating the intersection curve, Convert Entities can project it onto the active sketch plane for further use.

4. Final Answer:

   Use Intersection Curve to create the intersection lines, then Convert Entities to project them onto your sketch plane -> Option B

5. Quick Check:

   Intersection Curve + Convert Entities = accurate sketch [OK]

Hint: Combine Intersection Curve and Convert Entities for angled intersections [OK]

Common Mistakes:

• Trying to convert cylinder edges directly without intersection
• Drawing intersection manually causing inaccuracies
• Using Extrude tool which is unrelated