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Featured Model of the Day

Pot STL file, inner: base Ø40 mm, top Ø40 mm, height 40 mm - wall thickness 2 mm 📦 #2457

1 object(s) - format STL

gizmo

Latest user-generated 3D models

Tube adapter STL file ⌀ 147–141 mm (Length: 115 mm) 📦 #12122

1 object(s) - format STL

gizmo

From the Blog

Why Modeling Strategy Matters in Procedural CAD Modeling

2025-12-14 · 3D Modeling · sylvain
why Modeling Strategy Matters in Procedural CAD Modeling why Modeling Strategy Matters in Procedural CAD Modeling

Why does modeling strategy matter so much in procedural CAD? Two scripts can produce the exact same geometry while showing very different generation times.

Using a concrete build123d example, this article explains why certain operations, such as fillets, become expensive when repeated at scale, and how a simple change in approach can drastically reduce computation time.

A clear overview of the key challenges in procedural modeling, highlighting the direct impact of design choices on CAD engine performance.

Read the article

A selection of custom 3D models

📦 Model #2108

2 object(s)
- format STL
Small parts organizer with 9 drawers 60×45×150 mm STL 3D file, thickness: 4 mm
Small parts organizer with 9 drawers 60×45×150 mm STL 3D file, thickness: 4 mm
View of object #0
File of a storage box with drawers in 3D STL format. This model includes 9 compartments, arranged in 3 rows and 3 columns. In detail, this means 3 rows of 3 compartments. Each compartment offers a storage volume of 60 mm wide, 45 mm high, and 150 mm deep. The wall thickness is 4 mm, which makes the structure very sturdy. The overall dimensions of the structure measure 221.5 x 164.5 x 162 mm. All the objects in this model were designed to be printed without support.
Parameter Value Unit
number of rows 3
number of columns 3
inner drawer depth 150 mm
inner drawer width 60 mm
inner drawer height 45 mm
wall thickness 4 mm
removable divider none

📦 Model #1063

1 object(s)
- format STL
Multi-compartment box STL 3D file: 36 compartments of 17×17×80 mm
Multi-compartment box STL 3D file: 36 compartments of 17×17×80 mm
This printable multi-compartment box features 36 compartments measuring 17×17×80 mm each, with an almost cylindrical shape. Overall dimensions are 116×116×82 mm.
Parameter Value Unit
number of rows 6
number of columns 6
compartment length 17 mm
compartment width 17 mm
compartment height 80 mm
wall thickness 2 mm
compartment fillet (radius) 8.4 mm

📦 Model #4475

1 object(s)
- format STL
Tube adapter STL 3D file ⌀ 40–37 mm (Length: 118 mm)
Tube adapter STL 3D file ⌀ 40–37 mm (Length: 118 mm)
Straight tube fitting ⌀40 mm to ⌀37 mm in STL format. Total length of this connector is 118 mm. The thickness of the tubes is identical: 5 mm. The larger-diameter tube has a sleeve length of 38 mm, the smaller one of 40 mm. The ends have a fillet to make tube connection easier.
Parameter Value Unit
side A length 38 mm
side A outer diameter 40 mm
side A thickness 5 mm
side B length 40 mm
side B outer diameter 37 mm
side B thickness 5 mm
transition length 40 mm
axis offset 0 mm
ends fillet fillet on bo...

📦 Model #4476

1 object(s)
- format STL
Tubing adapter STL 3D file ⌀ 40–37 mm (Length: 115 mm)
Tubing adapter STL 3D file ⌀ 40–37 mm (Length: 115 mm)
Tube adapter ⌀40 mm to ⌀37 mm in STL 3D format. Length of this connector is 115 mm. The thickness of the tubes is identical: 5 mm. The larger-diameter tube has a sleeve length of 35 mm, the smaller one of 40 mm. The ends are rounded to facilitate the connection of the two tubes.
Parameter Value Unit
side A length 35 mm
side A outer diameter 40 mm
side A thickness 5 mm
side B length 40 mm
side B outer diameter 37 mm
side B thickness 5 mm
transition length 40 mm
axis offset 0 mm
ends fillet fillet on bo...

📦 Model #4414

2 object(s)
- format STL
Round box with lid STL 3D file ⌀ 134 mm - Height: 20 mm, Shell: 2 mm
Round box with lid STL 3D file ⌀ 134 mm - Height: 20 mm, Shell: 2 mm
View of object #0
Get this circular box model in 3D STL format. Its diameter is 134 mm and its total height is 20 mm. The wall thickness is 2 mm. A fillet located at the bottom of the box makes it easier to grip objects.
Parameter Value Unit
external diameter 134 mm
total height 20 mm
wall thickness 2 mm
fit clearance 0.2 mm
inner bottom fillet 1 mm

📦 Model #2668

1 object(s)
- format STL
Round-to-Rectangular Tube Adapter STL file ⌀81 mm to 120×70 mm, thickness 2 mm
Round-to-Rectangular Tube Adapter STL file ⌀81 mm to 120×70 mm, thickness 2 mm
3D file in STL format of a round-to-rectangular adapter with an outer diameter of ⌀81 mm and a rectangular section with internal dimensions 120×70 mm. The wall thickness is 2 mm and the total length is 110 mm.
Parameter Value Unit
cylinder outer diameter 81 mm
cylinder inlet length 10 mm
rectangle internal length 120 mm
rectangle internal height 70 mm
rectangle inlet length 5 mm
offset Z 0 mm
offset Y 0 mm
total length 110 mm
thickness 2 mm
chamfer no chamfer

📦 Model #4403

1 object(s)
- format STL
O-ring STL file ID 46.8 × CS 2.2 mm
O-ring STL file ID 46.8 × CS 2.2 mm
3D file of circular seal with ID 46.8 mm / CS 2.2  mm. Final diameter resulting corresponds to 51.2 mm.
Parameter Value Unit
inner diameter (ID) 46.8 mm
cross section (CS) 2.2 mm

📦 Model #2741

2 object(s)
- format STL
Small parts organizer with 20 drawers 47×21×120 mm STL 3D file, thickness: 2 mm
Small parts organizer with 20 drawers 47×21×120 mm STL 3D file, thickness: 2 mm
View of object #0
3D model of a drawer organizer in STL format. This model features 20 boxes, arranged in 5 rows and 4 columns. Practically speaking, this means 5 rows of 4 boxes. Each box comes with an inner space of 47 mm wide, 21 mm high, and 120 mm deep. The wall thickness is 2 mm. The overall dimensions of the structure come to 216 x 129.5 x 126 mm. All the objects in this model were designed to be printed without support.
Parameter Value Unit
number of rows 5
number of columns 4
inner drawer depth 120 mm
inner drawer width 47 mm
inner drawer height 21 mm
wall thickness 2 mm
removable divider none

📦 Model #2341

1 object(s)
- format STL
Washer / Flat Gasket STL 3D file ⌀ID: 16.5 mm ⌀OD: 25.0 mm thickness: 3.5 mm
Washer / Flat Gasket STL 3D file ⌀ID: 16.5 mm ⌀OD: 25.0 mm thickness: 3.5 mm
File of washer / gasket in STL format. This part has an inner diameter of ⌀16.5 mm and an outer diameter of ⌀25.0 mm. The total thickness is 3.5 mm. This part has no finish present.
Parameter Value Unit
inner diameter 16.5 mm
outer diameter 25.0 mm
thickness 3.5 mm
finish none

📦 Model #3491

1 object(s)
- format STL
Protective grid STL file, center-to-center: 107x107mm, mesh: 10mm - Ø5mm
Protective grid STL file, center-to-center: 107x107mm, mesh: 10mm - Ø5mm
3D square protective honeycomb grid model as a STL file. Mounting holes are placed at the four corners (center-to-center 107x107 mm), each with a diameter of Ø5 mm. The overall dimensions reach 117x117 mm, with very large 10 mm cell size for maximum airflow. This grid serves as both a protective guard and a ventilation panel.
Parameter Value Unit
length or center-to-center 107 mm
width or center-to-center 107 mm
mesh size 10 mm
dual color no
holes yes
hole diameter 5 mm

📦 Model #3424

1 object(s)
- format STL
Tubing adapter STL file ⌀ 115–65 mm (Length: 100 mm)
Tubing adapter STL file ⌀ 115–65 mm (Length: 100 mm)
Inline tubing adapter ⌀115 mm to ⌀65 mm in STL format. Length of this fitting is 100 mm. The thickness of the tubes is identical: 2 mm. The larger-diameter tube has a sleeve length of 30 mm, the smaller one of 40 mm. The ends are rounded on the outside.
Parameter Value Unit
side A length 30 mm
side A outer diameter 115 mm
side A thickness 2 mm
side B length 40 mm
side B outer diameter 65 mm
side B thickness 2 mm
transition length 30 mm
axis offset 0 mm
ends fillet fillet on th...

📦 Model #1616

1 object(s)
- format STL
Round-to-Rectangular Tube Adapter STL file ⌀100 mm to 150×50 mm, thickness 2 mm
Round-to-Rectangular Tube Adapter STL file ⌀100 mm to 150×50 mm, thickness 2 mm
File in STL format of a round-to-rectangular adapter with an external diameter of ⌀100 mm and a rectangular section with inner dimensions 150×50 mm. The wall thickness is 2 mm and the overall length is 150 mm. A chamfer is applied on the outside of the cylindrical end to ease insertion.
Parameter Value Unit
cylinder outer diameter 100 mm
cylinder inlet length 50 mm
rectangle internal length 150 mm
rectangle internal height 50 mm
rectangle inlet length 40 mm
offset Z 0 mm
offset Y 0 mm
total length 150 mm
thickness 2 mm
chamfer chamfer on t...

📦 Model #4503

1 object(s)
- format STL
Tube adapter STL 3D file ⌀ 125–80 mm (Length: 105 mm)
Tube adapter STL 3D file ⌀ 125–80 mm (Length: 105 mm)
Straight tube coupler ⌀125 mm to ⌀80 mm in STL format. Total length of this junction is 105 mm. The thickness of the tubes is identical: 5 mm. The larger-diameter tube has a sleeve length of 35 mm, the smaller one of 40 mm. The ends are raw.
Parameter Value Unit
side A length 35 mm
side A outer diameter 125 mm
side A thickness 5 mm
side B length 40 mm
side B outer diameter 80 mm
side B thickness 5 mm
transition length 30 mm
axis offset 0 mm
ends fillet no fillet

📦 Model #1483

1 object(s)
- format STL
Tube adapter STL file ⌀ 200–50 mm (Length: 80 mm)
Tube adapter STL file ⌀ 200–50 mm (Length: 80 mm)
Tube reducer ⌀200 mm to ⌀50 mm in STL 3D format. Total length of this junction is 80 mm. The thickness of the tubes is identical: 3 mm. The larger-diameter tube has a sleeve length of 30 mm, the smaller one of 30 mm as well. The ends have no fillet.
Parameter Value Unit
side A length 30 mm
side A outer diameter 200 mm
side A thickness 3 mm
side B length 30 mm
side B outer diameter 50 mm
side B thickness 3 mm
transition length 20 mm
axis offset 0 mm
ends fillet no fillet

📦 Model #2907

1 object(s)
- format STL
Honeycomb grid STL file, center-to-center: 75x75mm, mesh: 10mm - Ø8mm
Honeycomb grid STL file, center-to-center: 75x75mm, mesh: 10mm - Ø8mm
Download this 3D square grid file in STL format. Mounting holes are placed at the four corners (center-to-center 75x75 mm), each with a diameter of Ø8 mm. The overall dimensions reach 91x91 mm, with very open 10 mm cell size for peak ventilation. This grid serves as both a protective guard and a ventilation panel.
Parameter Value Unit
length or center-to-center 75 mm
width or center-to-center 75 mm
mesh size 10 mm
dual color no
holes yes
hole diameter 8 mm

📦 Model #2173

1 object(s)
- format STL
Pipe elbow STL file 10° ⌀OD: 57.2 mm ⌀ID: 49.2 mm thickness: 4 mm
Pipe elbow STL file 10° ⌀OD: 57.2 mm ⌀ID: 49.2 mm thickness: 4 mm
3D file of a pipe elbow with a 10° angle in STL format. This pipe elbow features an outer diameter of 57.2 mm and an inner diameter of 49.2 mm. The tube thickness is therefore 4 mm. End fillets make it easier to assemble.
Parameter Value Unit
outer diameter 57.2 mm
inner diameter 49.2 mm
angle 10 °
end fillets yes

📦 Model #4415

2 object(s)
- format STL
Round box with lid STL file ⌀ 115 mm - Height: 42 mm, Shell: 3 mm
Round box with lid STL file ⌀ 115 mm - Height: 42 mm, Shell: 3 mm
View of object #0
Get this circular organizing box in 3D STL format. Its diameter is 115 mm and its total height is 42 mm. The wall width is 3 mm. A fillet located at the bottom of the box makes it easier to grab objects.
Parameter Value Unit
external diameter 115 mm
total height 42 mm
wall thickness 3 mm
fit clearance 0.2 mm
inner bottom fillet 1 mm

📦 Model #779

1 object(s)
- format STL
Rectangular prism STL file 100×18×81 mm
Rectangular prism STL file 100×18×81 mm
Download an STL 3D model of a rectangular prism. Its overall dimensions are 100 by 18 by 81 mm. A fillet smooths the edges.
Parameter Value Unit
length 100 mm
width 18 mm
height 81 mm
fillet radius 1 mm

📦 Model #4497

1 object(s)
- format STL
Tubing adapter STL 3D file ⌀ 32–19 mm (Length: 65 mm)
Tubing adapter STL 3D file ⌀ 32–19 mm (Length: 65 mm)
Tube fitting ⌀32 mm to ⌀19 mm in STL 3D format. Length of this junction is 65 mm. The thickness of the tubes is identical: 2 mm. The larger-diameter tube has a sleeve length of 35 mm, the smaller one of 20 mm. The ends are not rounded.
Parameter Value Unit
side A length 35 mm
side A outer diameter 32 mm
side A thickness 2 mm
side B length 20 mm
side B outer diameter 19 mm
side B thickness 2 mm
transition length 10 mm
axis offset 0 mm
ends fillet no fillet

📦 Model #1639

1 object(s)
- format STL
Multi-compartment box STL 3D file: 16 compartments of 50×50×100 mm
Multi-compartment box STL 3D file: 16 compartments of 50×50×100 mm
This storage box design features 16 storage spaces measuring 50×50×100mm each. Overall dimensions of the box are 220×220×104mm. A 3mm fillet applied to each compartment help with item retrieval stored in the box. The walls are particularly robust.
Parameter Value Unit
number of rows 4
number of columns 4
compartment length 50 mm
compartment width 50 mm
compartment height 100 mm
wall thickness 4 mm
compartment fillet (radius) 3 mm

📦 Model #3502

1 object(s)
- format STL
Protective grid STL 3D file, 60x60mm, mesh: 8mm
Protective grid STL 3D file, 60x60mm, mesh: 8mm
Download this 3D square honeycomb grid model in STL format. The overall size is 60x60 mm, with wide 8 mm cell size for optimal air circulation. This type of grid serves both protection and ventilation roles.
Parameter Value Unit
length or center-to-center 60 mm
width or center-to-center 60 mm
mesh size 8 mm
dual color no
holes no

📦 Model #2179

2 object(s)
- format STL
Small parts organizer with 25 drawers 20×25×23 mm STL 3D file, thickness: 2 mm
Small parts organizer with 25 drawers 20×25×23 mm STL 3D file, thickness: 2 mm
View of object #0
Download this model of a multi-drawer unit in 3D STL format. This model features 25 drawers, arranged in 5 rows and 5 columns. Practically speaking, this means 5 rows of 5 drawers. Each drawer has usable dimensions of 20 mm wide, 25 mm high, and 23 mm deep. The wall thickness is 2 mm. The overall dimensions of the box are 134.5 x 149.5 x 29 mm. All the objects in this model were designed to be printed without support generation.
Parameter Value Unit
number of rows 5
number of columns 5
inner drawer depth 23 mm
inner drawer width 20 mm
inner drawer height 25 mm
wall thickness 2 mm
removable divider none

📦 Model #4145

1 object(s)
- format STL
Honeycomb grille STL file, 195x80mm, mesh: 7mm
Honeycomb grille STL file, 195x80mm, mesh: 7mm
Download this rectangular protective grid file in STL format. The overall size is 195x80 mm, with wide 7 mm cell size to enhance ventilation. This grid acts as a protective guard while allowing airflow.
Parameter Value Unit
length or center-to-center 195 mm
width or center-to-center 80 mm
mesh size 7 mm
dual color no
holes no

📦 Model #3057

1 object(s)
- format STL
Right-angle bracket 150×150 mm STL 3D file, thickness 6 mm, hole diameter 6 mm
Right-angle bracket 150×150 mm STL 3D file, thickness 6 mm, hole diameter 6 mm
3D file of a mounting bracket with a central reinforcement in STL format. The dimensions are 150 mm in length, 150 mm in height, 14 mm in width, and 6 mm in thickness. The screw holes are designed with a diameter of 6 mm. Chamfers are applied to the holes to improve the seating of the heads. The central reinforcement bar reduces bending and provides two clearances for screwdriver access. No support is needed to print this bracket, printed flat on the build plate.
Parameter Value Unit
length 150 mm
height 150 mm
width 14 mm
thickness 6 mm
hole diameter 6 mm
chamfer on the holes yes

📦 Model #4201

1 object(s)
- format STL
Washer / Flat Gasket STL 3D file ⌀ID: 3.9 mm ⌀OD: 6.9 mm thickness: 4.3 mm
Washer / Flat Gasket STL 3D file ⌀ID: 3.9 mm ⌀OD: 6.9 mm thickness: 4.3 mm
3D model of washer / gasket in STL 3D file format. This part features an inner diameter of ⌀3.9 mm and an outer diameter of ⌀6.9 mm. The total thickness is 4.3 mm. This part has no finish applied.
Parameter Value Unit
inner diameter 3.9 mm
outer diameter 6.9 mm
thickness 4.3 mm
finish none

📦 Model #2517

2 object(s)
- format STL
Small parts organizer with 16 drawers 30×20×65 mm STL file, thickness: 2 mm
Small parts organizer with 16 drawers 30×20×65 mm STL file, thickness: 2 mm
View of object #0
3D file of a sorting cabinet with drawers in 3D STL format. This model features 16 compartments, arranged in 4 rows and 4 columns. In detail, this means 4 rows of 4 compartments. Each compartment offers a storage volume of 30 mm wide, 20 mm high, and 65 mm deep. The wall thickness is 2 mm. The external dimensions of the structure come to 148 x 100 x 71 mm. All the objects in this model were designed to be printable without support generation.
Parameter Value Unit
number of rows 4
number of columns 4
inner drawer depth 65 mm
inner drawer width 30 mm
inner drawer height 20 mm
wall thickness 2 mm
removable divider none

📦 Model #3612

1 object(s)
- format STL
Protective grid STL 3D file, center-to-center: 210x110mm, mesh: 10mm - Ø5mm
Protective grid STL 3D file, center-to-center: 210x110mm, mesh: 10mm - Ø5mm
Download this rectangular protective honeycomb grid model in STL format. Mounting holes are placed at the four corners (center-to-center 210x110 mm), each with a diameter of Ø5 mm. The overall dimensions reach 220x120 mm, with very large 10 mm cell size for peak ventilation. This grid serves as both a protective guard and a ventilation panel.
Parameter Value Unit
length or center-to-center 210 mm
width or center-to-center 110 mm
mesh size 10 mm
dual color no
holes yes
hole diameter 5 mm

📦 Model #2405

3 object(s)
- format STL
Small parts organizer with 6 drawers 30×30×60 mm STL 3D file, thickness: 3 mm
Small parts organizer with 6 drawers 30×30×60 mm STL 3D file, thickness: 3 mm
View of object #0
File of a storage case in 3D STL format. This model contains 6 boxes, arranged in 2 rows and 3 columns. Specifically, this means 2 rows of 3 boxes. Each box comes with an inner space of 30 mm wide, 30 mm high, and 60 mm deep. The wall thickness is 3 mm, which makes the structure sturdy. The boxes feature 2 dividers each, which allows up to 3 compartments per box and up to 18 sections in total. The total size of the box come to 121.5 x 76 x 69 mm. All the objects in this model are intended to be printed without support.
Parameter Value Unit
number of rows 2
number of columns 3
inner drawer depth 60 mm
inner drawer width 30 mm
inner drawer height 30 mm
wall thickness 3 mm
removable divider two divider ...

📦 Model #2390

1 object(s)
- format STL
Round air vent STL 3D file ∅ 115 mm, slat angle: 45°
Round air vent STL 3D file ∅ 115 mm, slat angle: 45°
3D file of a round grille for air circulation in STL format. Its male diameter is 115 mm. The slats have an angle of 45° and a high thickness of 2 mm. This ventilation grille has a collar of 10 mm. The full diameter of this model is 135 mm.
Parameter Value Unit
male diameter 115 mm
slat angle 45 °
slat thickness 2 mm
flange width 10 mm
central reinforcement no

📦 Model #4396

1 object(s)
- format STL
Honeycomb grid STL file, 250x250mm, mesh: 10mm
Honeycomb grid STL file, 250x250mm, mesh: 10mm
Square grid model as a STL file. The overall size is 250x250 mm, with very large 10 mm cell size for maximum airflow. This grid serves as both a protective guard and a ventilation panel.
Parameter Value Unit
length or center-to-center 250 mm
width or center-to-center 250 mm
mesh size 10 mm
dual color no
holes no

STL: Advantages and Disadvantages for 3D Printing

The STL format is, without question, a cornerstone of 3D printing. This exchange format has established itself as the universal standard for representing 3D models ever since the early days of stereolithography. Its main strength lies in its simplicity: it describes the surface of an object using countless small triangles that form a mesh. This approach, known as tessellation, makes STL 3D files universally compatible with nearly all CAD software and slicers. If you’d like to learn more about this format, check out our article STL: What Is This 3D File Format?.

One of the major advantages of the format lies in this universality: whether you’re using a complex modeling program or a simpler design tool, you can export your 3D models in STL 3D format with near certainty that they’ll be interpreted correctly by your 3D printer. This ease of exchange has played a key role in the widespread adoption of 3D printing, allowing anyone to share and print objects without worrying about software compatibility. Once again, simplicity is its greatest strength.

However, that same simplicity also brings certain limitations. The triangle mesh, while effective for describing geometry, contains no information about colors, textures, or materials. For more advanced projects requiring these details, the STL format starts to show its weaknesses. Additionally, print quality depends directly on the fineness of the tessellation: too few triangles can lead to rough or faceted surfaces, while an overly dense mesh can make the file unnecessarily heavy.

Another notable drawback is the lack of unit management. An STL file doesn’t specify whether dimensions are in millimeters, centimeters, or inches, which can sometimes cause scaling errors when importing into a slicer. Despite these limitations, the STL format remains the go-to standard for converting your 3D models into G-code — the language your printer understands. It continues to be the preferred choice for its robustness and broad compatibility, even as newer formats like 3MF emerge for more specialized needs.

What is parametric modeling?

Parametric modeling is a fundamental approach in computer-aided design (CAD) that reshapes how 3D models are created and managed. Far from being a simple drawing technique, it represents a genuine design philosophy where objects are defined not by fixed shapes, but by variables and intelligent relationships.

This method makes it possible to modify the length, width, or diameter of a part and have the entire design adapt automatically, without the need to redraw everything. At the core of the process are parameters—numerical values (length, angle, thickness, etc.)—linked together through constraints and formulas. For instance, the diameter of a hole can be defined as half the width of a plate; if the width changes, the hole’s diameter instantly adjusts, ensuring the consistency of the design. This interdependence makes 3D models flexible and responsive to changes. One of the main advantages of parametric modeling lies in its ability to simplify customization and enable rapid iteration of designs.

Whether through modeling software such as Fusion 360 or FreeCAD, or through code-based libraries like build123d, this approach allows effortless exploration of a wide range of variations. Such flexibility is especially valuable across multiple fields—from mechanical engineering and architecture to consumer product design. It saves considerable time, reduces errors, and improves the performance of parts.

By defining design intent from the start through these parameters and constraints, the model preserves its integrity and functionality even after numerous modifications. It is a powerful way to transform an idea into a tangible object, ready to adapt to new situations.