Part Attachment
Menu location 

Part → Attachment... 
Workbenches 
Part, PartDesign 
Default shortcut 
None 
Introduced in version 
0.17 
See also 
Placement, Basic Attachment Tutorial 
Contents

Description
Attachment is a utility to attach an object to another one. The attached object is linked to the other object, which means that if the latter's placement is changed afterwards, the attached object will update to its new position.
Usage
 Select the object to be attached.
 Go to the Part → Attachment... menu.
 Note: when working in PartDesign and creating sketches, datum geometry or primitives, steps 1 and 2 are unnecessary: the Attachment dialogue is brought up automatically.
 Under Attachment parameters, Not attached can be read. The first button below is labeled Selecting… to indicate it is expecting a selection in the 3D view.
 Select a topology element on the object to attach to: vertex, edge or face/plane. Datum geometry from Part containers are also selectable.
 The first button's label now adopts the type of topology selected. In the white field to its right, the referenced object and its element is added. For example, if a face on a primitive cube is selected, the field will show Box:Face6.
 Select an Attachment mode in the list. The available modes are filtered by the selected references. Attached with mode <mode description> will be displayed under the Attachment header.
 For live information on the attachment modes, hover the mouse on top of one of the modes in the list for a tooltip to appear.
 Optionally, add up to 3 more references by pressing the Reference2, Reference3, and Reference4 buttons and repeating step 4.
 Optionally set an Attachment Offset.
 Press OK.
Options
Attachment mode
Deactivated
Default, no reference selected.
Normal to edge
Object is made perpendicular to edge. Optional vertex reference defines location.
 Reference combinations
 Edge
 Edge, Vertex
 Vertex, Edge
Align ONX
Matches object's origin with first referenced vertex, then aligns its normal and horizontal plane axis toward vertex/along line.
 Reference combinations
 Vertex, Vertex, Vertex
 Vertex, Vertex, Edge
 Vertex, Edge, Vertex
 Vertex, Edge, Edge
 Vertex, Vertex
 Vertex, Edge
Align ONY
Matches object's origin with first referenced vertex and aligns its normal and vertical plane axis toward vertex/along line.
 Reference combinations
 Vertex, Vertex, Vertex
 Vertex, Vertex, Edge
 Vertex, Edge, Vertex
 Vertex, Edge, Edge
 Vertex, Vertex
 Vertex, Edge
Align OXY
Matches object's origin with first referenced vertex and aligns its horizontal and vertical plane axes toward vertex/along line.
 Reference combinations
 Vertex, Vertex, Vertex
 Vertex, Vertex, Edge
 Vertex, Edge, Vertex
 Vertex, Edge, Edge
 Vertex, Vertex
 Vertex, Edge
Align OXN
Matches object's origin with first referenced vertex and aligns its horizontal plane axis and normal toward vertex/along line.
 Reference combinations
 Vertex, Vertex, Vertex
 Vertex, Vertex, Edge
 Vertex, Edge, Vertex
 Vertex, Edge, Edge
 Vertex, Vertex
 Vertex, Edge
Align OYN
Matches object's origin with first referenced vertex and aligns its vertical plane axis and normal toward vertex/along line.
 Reference combinations
 Vertex, Vertex, Vertex
 Vertex, Vertex, Edge
 Vertex, Edge, Vertex
 Vertex, Edge, Edge
 Vertex, Vertex
 Vertex, Edge
Align OYX
Matches object's origin with first referenced vertex and aligns its vertical and horizontal plane axes toward vertex/along line.
 Reference combinations
 Vertex, Vertex, Vertex
 Vertex, Vertex, Edge
 Vertex, Edge, Vertex
 Vertex, Edge, Edge
 Vertex, Vertex
 Vertex, Edge
Translate origin
Object's origin is aligned to matched vertex. Orientation is controlled by Placement property.
 Reference combinations
 Vertex.
Object's XY
Plane is aligned to XY local plane of linked object.
 Reference combinations
 Any, Conic.
Object's XZ
Plane is aligned to XZ local plane of linked object.
 Reference combinations
 Any, Conic.
Object's YZ
Plane is aligned to YZ local plane of linked object.
 Reference combinations
 Any, Conic
Plane face
Plane is aligned to coincide to planar face.
 Reference combinations
 Plane
Tangent to surface
Plane is made tangent to surface at vertex.
 Reference combinations
 Face, Vertex
 Vertex, Face
Frenet NB
Plane is set to normalbinormal (NB) axes of FrenetSerret coordinates at the point of the edge's curve that is closest to the vertex (or defined by MapPathParameter property, if vertex is not linked). The object's origin is translated to the vertex if the vertex is first, or kept at the curve if edge is first. This mode is similar to Normal to edge, except that X axis is welldefined.
Frenet TN
Plane is set to tangentnormal (TN) axes of FrenetSerret coordinates at the point of the edge's curve that is closest to the vertex (or defined by MapPathParameter property, if vertex is not linked). The origin of sketch is translated to the vertex if the vertex is first, or kept at the curve if edge is first. Effectively, if the curve is planar, the sketching plane is the plane of the curve.
Frenet TB
Plane is set tangentbinormal (TB) axes of FrenetSerret coordinates at the point of the edge's curve that is closest to the vertex (or defined by MapPathParameter property, if vertex is not linked). The origin of sketch is translated to the vertex if the vertex is first, or kept at the curve if edge is first.
Concentric
Aligns to plane to osculating circle of an edge. Optional Vertex link defines where.
 Reference combinations
 Curve
 Circle
 Curve, Vertex
 Circle, Vertex
 Vertex, Curve
 Vertex, Circle
Revolution Section
Plane is perpendicular to edge, and Y axis is matched with axis of osculating circle. Optional Vertex link defines where.
 Reference combinations
 Curve
 Circle
 Curve, Vertex
 Circle, Vertex
 Vertex, Curve
 Vertex, Circle
Plane by 3 points
Aligns XY plane to pass through three vertices.
 Reference combinations
 Vertex, Vertex, Vertex
 Line, Vertex
 Vertex, Line
 Line, Line
Normal to 3 points
Aligns plane to pass through first two vertices, and perpendicular to plane that passes through 3 vertices.
 Reference combinations
 Vertex, Vertex, Vertex
 Line, Vertex
 Vertex, Line
 Line, Line
Folding
Specialty mode for folding polyhedra. Select 4 edge in order: foldable edge, fold line, other fold line, other foldable edge. Plane will be aligned to folding the first edge. In the picture below, it is not required that both leafs to fold together be the same.
Inertia 23
Object will be attached to a plane passing through second and third principal axes of inertia (passes through center of mass).
 Reference combinations
 Any
 Any, Any
 Any, Any, Any
 Any, Any, Any, Any
Attachment Offset
Attachment Offset is used to apply a linear or rotary offset from the referenced object. That means the offsets are relative to the local coordinate system, not to the global. It becomes active when an attachment mode other than Deactivated has been selected.
 X: sets an offset distance in the X axis of the reference object.
 Y: sets an offset distance in the Y axis of the reference object.
 Z: sets an offset distance in the Z axis of the reference object. This coordinate is to be used for the frequent use case that you want to offset a sketch perpendicular to the plane.
 Yaw: rotates the attached object along the reference object's Z axis.
 Pitch: rotates the attached object along the reference object's Y axis.
 Roll: rotates the attached object along the reference object's X axis.
 Flip sides: if checked, the attached object is reversed from its XY plane.
Limitations
 Part and Body containers are not supported. While it's possible to use Attachment to align them, the attachment won't be parametrically linked.
 If selecting two lines results in a traceback with "points are collinear. Can't make a plane", try selecting three points instead [1].
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