Additive Wedge¶

In one sentence: Add a solid wedge — a box whose top face is independently sized and offset from its bottom face — directly into a Part Design Body, fusing it with any existing material.

Overview¶

Workbench: Part Design · Menu: Part Design → Additive Primitives → Additive Wedge
Toolbar: Part Design Modeling Primitives · Shortcut: none

Additive Wedge inserts a parametric wedge solid into the active Body and fuses it with the existing shape. A wedge is defined by two rectangular faces — one at the bottom (Y = Ymin) and one at the top (Y = Ymax) — each described by its own X and Z extents. Because the top face can be independently sized and horizontally offset from the bottom face, you can create classic tapered wedges, ramps, pyramids with rectangular bases, and any general linear solid that transitions between two rectangles. No sketch is required.

Intuition¶

Think of a wedge as a box that you can squash, tilt, or taper. The bottom face sits in the XZ-plane at height Y = Ymin. It spans from Xmin to Xmax along X, and from Zmin to Zmax along Z. The top face sits at Y = Ymax. It has its own independent extents: X2min to X2max along X, and Z2min to Z2max along Z.

Connecting these two rectangles with straight lines gives you the wedge solid. If the top face is the same size and position as the bottom face you get a rectangular box. If the top face is smaller and centred you get a truncated pyramid. If the top face is zero-sized (X2min = X2max and Z2min = Z2max at the same value) you get a full pyramid that comes to an edge or a point at the top.

Because the top face can be offset horizontally — not just scaled — you can produce ramp shapes where the top face is the same size as the bottom but slid along X or Z. This gives a true wedge/ramp, useful for support brackets, cam shapes, and tapered spacers.

The ten parameters fully describe the geometry; there is no redundancy. All coordinates are in the local coordinate system of the Body origin.

When to use it¶

You need a simple ramp, wedge, or shim — a shape that is thick on one side and thin on the other.
You are modelling a door stop, tapered cleat, bracket gusset, or any part with a linearly varying profile.
You need a pyramid or truncated pyramid (frustum with a rectangular base) as a design element or stand-alone solid.
You want to block in a draft-angle tapered boss without constructing a lofted sketch, and the cross-section transitions between two rectangles.

When NOT to use it¶

The cross-section is not a rectangle at both ends — use Additive Loft with custom profile sketches for arbitrary transitions.
You need a wedge-shaped cut rather than added material — use Subtractive Wedge, which has identical parameters but removes material.
The taper is conical or elliptical — use Additive Cone or Additive Ellipsoid for rounded shapes.
The dimensions are driven by relations to other geometry — if you need a wedge whose dimensions are derived from existing faces or edges, a lofted profile sketch with constraints will be more maintainable.

Step-by-step walkthrough¶

Prerequisites: An active Part Design Body in the document. The wedge can be the very first feature (no existing solid required).

Open or create a document and ensure a Body is active. FreeCAD will offer to create one automatically if none exists.
Activate Part Design → Additive Primitives → Additive Wedge from the menu, or click its icon in the Part Design Modeling Primitives toolbar (expand the drop-down if needed).
The task panel opens. Understand the coordinate layout before entering values:
Bottom face (at Y = Ymin): spans Xmin → Xmax in X and Zmin → Zmax in Z.
Top face (at Y = Ymax): spans X2min → X2max in X and Z2min → Z2max in Z.
Set the bottom face extents: enter values for Xmin, Xmax, Zmin, and Zmax. For a bottom face that starts at the origin with dimensions 10 × 10 mm, use Xmin=0, Xmax=10, Zmin=0, Zmax=10.
Set the height: enter Ymin (typically 0) and Ymax (the height of the wedge, e.g. 10).
Set the top face extents: enter X2min, X2max, Z2min, and Z2max. For a simple tapered ramp, set these to the same X range but shift them along Z: e.g. X2min=2, X2max=8, Z2min=2, Z2max=8 produces a centred truncated pyramid.
Click OK. The wedge is fused into the Body and appears in the model tree as Wedge.

Tip

To create a classic right-angled ramp (thick at one end, pointed at the other), set the top face to a zero-width edge: X2min = X2max (e.g., both = 5 for the midpoint). The wedge will have a sharp ridge at the top instead of a flat face.

Parameters¶

All ten parameters are App::PropertyDistance values in mm.

The bottom face is at Y = Ymin. The top face is at Y = Ymax.

Parameter	Type	Default	Description
Xmin	Distance (mm)	0.0	Minimum X coordinate of the bottom face.
Ymin	Distance (mm)	0.0	Y coordinate of the bottom face (the base height).
Zmin	Distance (mm)	0.0	Minimum Z coordinate of the bottom face.
X2min	Distance (mm)	2.0	Minimum X coordinate of the top face. Can be offset from Xmin.
Z2min	Distance (mm)	2.0	Minimum Z coordinate of the top face. Can be offset from Zmin.
Xmax	Distance (mm)	10.0	Maximum X coordinate of the bottom face. Must satisfy Xmax > Xmin.
Ymax	Distance (mm)	10.0	Y coordinate of the top face (the top height). Must satisfy Ymax > Ymin.
Zmax	Distance (mm)	10.0	Maximum Z coordinate of the bottom face. Must satisfy Zmax > Zmin.
X2max	Distance (mm)	8.0	Maximum X coordinate of the top face. X2max ≥ X2min required (can equal X2min for a ridge).
Z2max	Distance (mm)	8.0	Maximum Z coordinate of the top face. Z2max ≥ Z2min required.

Validity constraints enforced by FreeCAD:

Xmax − Xmin > 0 (bottom face has positive X width)
Ymax − Ymin > 0 (wedge has positive height)
Zmax − Zmin > 0 (bottom face has positive Z depth)
X2max − X2min ≥ 0 (top face X span can be zero — a ridge — but not negative)
Z2max − Z2min ≥ 0 (top face Z span can be zero but not negative)

Advanced usage¶

Creating a rectangular pyramid¶

Set the top face to a degenerate point or zero-size rectangle:

X2min = X2max = (Xmin + Xmax) / 2
Z2min = Z2max = (Zmin + Zmax) / 2

This produces a four-sided pyramid with a rectangular base. For a perfect square pyramid, ensure the bottom face is a square (Xmax − Xmin = Zmax − Zmin) and place the apex at the centre.

Creating an offset ramp (door stop / wedge shim)¶

A true ramp with the top face shifted along Z:

Xmin=0, Xmax=10, Zmin=0, Zmax=10, Ymin=0, Ymax=10
X2min=0, X2max=10, Z2min=5, Z2max=10

Here the bottom face is a 10×10 square and the top face is a 10×5 rectangle shifted to the far Z end, producing a ramp that is flat on one side and sloped on the other.

Asymmetric taper¶

Both the X and Z dimensions of the top face can be independently offset and sized, allowing a trapezoid frustum where each pair of opposite faces has a different taper angle. This level of control is unique to the Wedge — no other primitive exposes this many independent face coordinates.

Negative coordinates are allowed¶

All ten parameters accept negative values. Setting Xmin < 0 and Xmax > 0 places the bottom face straddling the Y-axis, which is useful when you want the wedge centred on a symmetry plane.

Common mistakes and pitfalls¶

Error: delta x of wedge too small

Cause: Xmax − Xmin is zero or negative — the bottom face has no width.
Fix: Ensure Xmax > Xmin. The same logic applies to Y (Ymax > Ymin) and Z (Zmax > Zmin).

Error: delta x2 of wedge is negative

Cause: X2max < X2min — the top face X range is inverted.
Fix: Ensure X2max ≥ X2min and Z2max ≥ Z2min. A value of zero is allowed (produces a top edge or point); negative values are not.

Wedge looks like a box — the taper has no visible effect

Cause: The top face (X2 and Z2) extents happen to match the bottom face extents exactly.
Fix: Change X2min, X2max, Z2min, or Z2max to values different from their bottom-face counterparts to introduce the taper.

Unexpected shape after changing only one parameter

Cause: Because all ten parameters interact to define both face rectangles and the height, changing one (for example, Xmax) without adjusting the top face (X2max) may produce an asymmetric shape unintentionally.
Fix: Think in terms of "what should the bottom face look like" and "what should the top face look like" and set all four bounds for each face independently.

Python API¶

Minimal example¶

import FreeCAD as App
import PartDesign

doc = App.newDocument()

body = doc.addObject("PartDesign::Body", "Body")

wedge = doc.addObject("PartDesign::AdditiveWedge", "Wedge")
body.addObject(wedge)

# Default wedge: bottom 10×10, top 6×6 (offset 2 on each side), height 10
# Xmin=0, Ymin=0, Zmin=0, X2min=2, Z2min=2
# Xmax=10, Ymax=10, Zmax=10, X2max=8, Z2max=8
doc.recompute()

print(f"Volume: {wedge.Shape.Volume:.4f} mm³")
# TODO: verify computed volume

Creating a simple ramp¶

wedge.Xmin  = 0.0
wedge.Xmax  = 20.0
wedge.Ymin  = 0.0
wedge.Ymax  = 5.0
wedge.Zmin  = 0.0
wedge.Zmax  = 10.0
# Top face: same X width, shifted to far Z edge (a ramp rising from Zmin to Zmax)
wedge.X2min = 0.0
wedge.X2max = 20.0
wedge.Z2min = 10.0   # top face collapses to a line at Zmax
wedge.Z2max = 10.0
doc.recompute()

Resulting feature properties¶

Property	Type	Description
`Xmin`	`App::PropertyDistance`	Minimum X of bottom face, mm.
`Ymin`	`App::PropertyDistance`	Y coordinate of bottom face (base level), mm.
`Zmin`	`App::PropertyDistance`	Minimum Z of bottom face, mm.
`X2min`	`App::PropertyDistance`	Minimum X of top face, mm.
`Z2min`	`App::PropertyDistance`	Minimum Z of top face, mm.
`Xmax`	`App::PropertyDistance`	Maximum X of bottom face, mm.
`Ymax`	`App::PropertyDistance`	Y coordinate of top face (wedge height), mm.
`Zmax`	`App::PropertyDistance`	Maximum Z of bottom face, mm.
`X2max`	`App::PropertyDistance`	Maximum X of top face, mm.
`Z2max`	`App::PropertyDistance`	Maximum Z of top face, mm.