Need to create simple 3D shapes but don't want to learn complex 3D modeling programs?
This intuitive online app is for you!

Note: This app is designed for PC/MAC. It is not suitable for tablets/phones..

A short example: Creating and printing a mounting bracket

Key features

Getting started

Axis follow the STL convention, all dimensions are in mm.

The basic principle is that Z=0 portions are not visible.

Draw the outline of the shape using the selection tools, then give it Z volume by using the shape tools.

Selection tools hints:

  • The current selection is displayed in green
  • Rectangular marquee - Use SHIFT for square
  • Elliptical marquee - Use SHIFT for circle
  • Line segment marquee - Use SHIFT for 45°/90° angles, ENTER or double click to close the contour

Shape tools hints:

  • Shape tools apply to the current selection (displayed in green)
  • Shape tools add/reduce volume from the current Z. Use SHIFT to start volume from Z=0

Simple examples: A washer, a nut, a button

STL processing: Extrude, Stamp, Symmetry, Mirror

  • In Extrude mode, the shape is closed by a Z=0 plane.
  • In Stamp mode, the shape is closed by walls of the given thickness.
    To be safe with most 3D printers do not use thickness below 1.5mm.
    Stamping adds "thickness" to the height (Z) from the shape.
  • In Symmetry mode, the shape is closed by symmetry around the Z=0 plane.
  • In Mirror mode, the shape is closed by a Z=0 plane, then mirrored around maximum Z.
    This allows very easy design of reels, holders, etc.

The Tilt Shape Tool

The Tilt Shape Tool is very useful in creating reinforcements.

Use Shift to constrain tilt to X or Y axis..


To use the Folding Tool :

First draw a rectangle with only one edge crossing the shape.
This determines the fold line.
Order of folds is important. Always start from the outside of the shape.

Use the Folding Tool with Shift to modify Z from folding line.

Negative Z

Drawing with negative Z is possible by selecting the corresponding
dig/grow tool

When processing STL:
  • In Extrude mode, the Z=0 plane crosses the shape
  • In Stamp mode, walls are built outside the negative Z portions of the shape.
    This increases the shape dimensions by 2 x material thickness.

Starting from images

This video shows how easy it is to extrude from an aluminum profile section.
For easier scaling, you may first position your image on the below build plane using an image editor.
This build plane is 1000 x 1000px for a print dimension of 100x100mm (1 pixel = 0.1 mm) doit3d build plane
Buid plane 1000x1000px
(right click to save)

Starting from top view drawings

Load a part top view drawing and use the "Magic marquee" tool to automatically select contours.
This video shows how to quickly create gearings and the functional print result.

Solid of revolution

3 examples are shown, including starting from an image to create a pawn of chess.
To merge selections, use the Ctrl key.
To revolve the shape, select the Spherical shape tool and use Ctrl+Shift

A practical example: Building a door hinge (male/female)

Controls Summary

Active selections are displayed in green (red for folds)

Name Action with Shift key with Ctrl key
Rectangular marquee Draw a rectangular selection Draw a square Merge with previous selection
Elliptical marquee Draw an elliptical selection Draw a circle Merge with previous selection
Free hand lasso Drag to draw a contour, release to close contour - Merge with previous selection
Line segments marquee Click to define new point, double click or Enter to close contour 0-45°-90°... angles if previous selection: merge
If no previous selection:
0-60°-90°...  angles
Magic marquee Click on a drawing to automatically select a contour. Works only with well contrasted drawings. - -
Move selection If new selection: Move it
If selection has volume: Duplicate it
Rotate selection -
Lock selection Use TAB to select (active selection is displayed in green) - -
Vertical Shape Add vertical volume (Z) to active selection Start from Z=0 -
Spherical Shape Add spherical volume to active selection Start from Z=0 Change to cylinder
Ctrl+Shift: Revolution volume
Soft Shape Add soft (cubical) volume to active selection Start from Z=0 -
Pyramidal Shape Add pyramidal volume to active selection Start from Z=0 -
Tilt Plane Tilt active selection, starts always from Z=0 Constrain to X or Y axis -
Fold Requires active rectangular selection, with only one edge crossing the shape. This edge defines the folding line. Z from folding is maxZ/2, maxZ being maximum Z from fold line.
Active folding selection is displayed in solid red, other foldings in dotted red.
Modify Z from folding -
Allow Z >= 0 only Default - -
No constraint on Z   - -
Allow Z <= 0 only   - -