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Featured Model of the Day

Color-coded compartment box STL 3D file: 16 compartments of 25×25×25 mm 📦 #1196

3 object(s) - format STL

gizmo

Latest user-generated 3D models

Washer / Flat Gasket STL 3D file ⌀ID: 190 mm ⌀OD: 220 mm thickness: 14 mm + chamfers 📦 #9658

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 #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 #3750

1 object(s)
- format STL
Tube elbow STL 3D file 110° ⌀OD: 60 mm ⌀ID: 54 mm thickness: 3 mm
Tube elbow STL 3D file 110° ⌀OD: 60 mm ⌀ID: 54 mm thickness: 3 mm
3D model of a tubing elbow with a 110° angle in STL format. This elbow features an outer diameter of 60 mm and an inner diameter of 54 mm. The tube thickness is therefore 3 mm. End fillets make it easier to assemble.
Parameter Value Unit
outer diameter 60 mm
inner diameter 54 mm
angle 110 °
end fillets yes

📦 Model #2961

1 object(s)
- format STL
L-bracket 130×105 mm STL file, thickness 5 mm, hole diameter 5 mm
L-bracket 130×105 mm STL file, thickness 5 mm, hole diameter 5 mm
Download this file of a corner bracket with a reinforcing bar in STL format. The dimensions are 130 mm in length, 105 mm in height, 14 mm in width, and 5 mm in thickness. The screw holes are designed with a diameter of 5 mm. Chamfers are applied to the holes for a cleaner fit of the screws. The central reinforcement bar enhances mechanical strength and includes two openings for fastening. Support generation is not required for printing this bracket, printed flat on the build plate.
Parameter Value Unit
length 130 mm
height 105 mm
width 14 mm
thickness 5 mm
hole diameter 5 mm
chamfer on the holes yes

📦 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

📦 Model #4056

1 object(s)
- format STL
Clip-on tube support Ø160 mm STL file · Flat head screw Ø10 mm
Clip-on tube support Ø160 mm STL file · Flat head screw Ø10 mm
Download this 3D file of a Ø160 mm custom pipe clip in STL format. The installation is done with a large flat head screw Ø10 mm. This pipe support clip is built for a firm hold and simple mounting.
Parameter Value Unit
tube diameter 160 mm
hole diameter 10 mm
countersunk screw yes

📦 Model #3921

1 object(s)
- format STL
Round air vent STL 3D file ∅ 93 mm, slat angle: 45° with central reinforcement
Round air vent STL 3D file ∅ 93 mm, slat angle: 45° with central reinforcement
File of a round grille for air circulation in STL format. Its insertion diameter is 93 mm. The slats have an angle of 45° and a high thickness of 2 mm. A centered vertical reinforcement strengthens the whole structure. This 3D vent cover has a thin flange of 4 mm. The full diameter of this model is 101 mm.
Parameter Value Unit
male diameter 93 mm
slat angle 45 °
slat thickness 2 mm
flange width 4 mm
central reinforcement yes

📦 Model #1791

2 object(s)
- format STL
Enclosure with screw-mounted lid STL file: 90×60×60 mm (with ventilation on the lid and under the enclosure)
Enclosure with screw-mounted lid STL file: 90×60×60 mm (with ventilation on the lid and under the enclosure)
View of object #0
Enclosure model with a screwed lid in STL format. The dimensions are 90 mm long by 60 mm wide and 60 mm high. The cover only is 10 mm high. Wall thickness is 2 mm. This enclosure has marked cooling area on the lid and under the base.
Parameter Value Unit
length 90 mm
width 60 mm
total height 60 mm
lid height 10 mm
wall thickness 2 mm
screw margin 0.1 mm
fit clearance 0.2 mm
cooling level 10
cooling zone(s) cutouts on b...

📦 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 #2275

1 object(s)
- format STL
Multi-compartment box STL 3D file: 20 compartments of 40×40×20 mm
Multi-compartment box STL 3D file: 20 compartments of 40×40×20 mm
This STL 3D model features 20 storage spaces measuring 40×40×20mm each. The total dimensions are 218×175×23mm. Fillets of 3mm applied to all compartments help with item retrieval stored in slots. The dividers are particularly solid.
Parameter Value Unit
number of rows 4
number of columns 5
compartment length 40 mm
compartment width 40 mm
compartment height 20 mm
wall thickness 3 mm
compartment fillet (radius) 3 mm

📦 Model #3706

1 object(s)
- format STL
Honeycomb grid STL 3D file, 245x245mm, mesh: 4mm
Honeycomb grid STL 3D file, 245x245mm, mesh: 4mm
Square protective honeycomb grid model as a STL file. The overall size is 245x245 mm, with standard 4 mm cell size for balanced airflow and protection. This type of grid serves both protection and ventilation roles.
Parameter Value Unit
length or center-to-center 245 mm
width or center-to-center 245 mm
mesh size 4 mm
dual color no
holes no

📦 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 #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 #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 #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 #1999

1 object(s)
- format STL
Round-to-Rectangular Tube Adapter STL 3D file ⌀50 mm to 32×32 mm, thickness 2 mm
Round-to-Rectangular Tube Adapter STL 3D file ⌀50 mm to 32×32 mm, thickness 2 mm
Download this 3D model in STL format of a round-to-rectangular tube adapter with an outer diameter of ⌀50 mm and a rectangular section with inner dimensions 32×32 mm. The wall thickness is 2 mm and the overall length is 100 mm.
Parameter Value Unit
cylinder outer diameter 50 mm
cylinder inlet length 25 mm
rectangle internal length 32 mm
rectangle internal height 32 mm
rectangle inlet length 15 mm
offset Z 0 mm
offset Y 0 mm
total length 100 mm
thickness 2 mm
chamfer no chamfer

📦 Model #4280

1 object(s)
- format STL
Corner bracket 200×200 mm STL file, thickness 10 mm, hole diameter 8 mm
Corner bracket 200×200 mm STL file, thickness 10 mm, hole diameter 8 mm
3D file of a right-angle bracket with a reinforcing bar in STL format. The dimensions are 200 mm in length, 200 mm in height, 40 mm in width, and 10 mm in thickness. The mounting holes are designed with a diameter of 8 mm. Chamfers are done to the holes to seat the screw heads. The central reinforcement bar enhances mechanical strength and provides two openings for screwdriver access. This bracket prints without support, lying flat on the print bed.
Parameter Value Unit
length 200 mm
height 200 mm
width 40 mm
thickness 10 mm
hole diameter 8 mm
chamfer on the holes yes

📦 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 #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 #3420

1 object(s)
- format STL
Protective grid STL 3D file, center-to-center: 38x38mm, mesh: 5mm - Ø3mm
Protective grid STL 3D file, center-to-center: 38x38mm, mesh: 5mm - Ø3mm
3D fan guard file in STL format. Mounting holes are placed at the four corners (center-to-center 38x38 mm), each with a diameter of Ø3 mm. The overall dimensions reach 44x44 mm, with regular 5 mm cell size for balanced airflow and protection. This grid functions as both a mechanical guard and a ventilation panel.
Parameter Value Unit
length or center-to-center 38 mm
width or center-to-center 38 mm
mesh size 5 mm
dual color no
holes yes
hole diameter 3 mm

📦 Model #1484

2 object(s)
- format STL
Round box with lid STL file ⌀ 96 mm - Height: 170 mm, Shell: 3 mm
Round box with lid STL file ⌀ 96 mm - Height: 170 mm, Shell: 3 mm
View of object #0
Download this cylindrical storage box in STL format. Its diameter is 96 mm and its height is 170 mm. The walls have a thickness of 3 mm. A fillet located at the bottom of the box makes it easier to grip objects located inside.
Parameter Value Unit
external diameter 96 mm
total height 170 mm
wall thickness 3 mm
fit clearance 1 mm
inner bottom fillet 2 mm

📦 Model #2410

1 object(s)
- format STL
Tube adapter STL file ⌀ 20–12 mm (Length: 50 mm)
Tube adapter STL file ⌀ 20–12 mm (Length: 50 mm)
Inline tube coupler ⌀20 mm to ⌀12 mm in STL format. Total length of this coupler is 50 mm. The thickness of the tubes is identical: 2 mm. The larger-diameter tube has a sleeve length of 20 mm, the smaller one of 20 mm as well. The ends have no fillet.
Parameter Value Unit
side A length 20 mm
side A outer diameter 20 mm
side A thickness 2 mm
side B length 20 mm
side B outer diameter 12 mm
side B thickness 2 mm
transition length 10 mm
axis offset 0 mm
ends fillet no fillet

📦 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 #3184

1 object(s)
- format STL
Round air vent STL file ∅ 60 mm, slat angle: 10° with central reinforcement
Round air vent STL file ∅ 60 mm, slat angle: 10° with central reinforcement
3D design of a round vent cover for air circulation in STL format. Its male diameter is 60 mm. The slats have a slight angle of 10° and a high thickness of 2 mm. A central reinforcement reinforces the whole structure. This 3D vent grille has a prominent flange of 20 mm. The full diameter of the model is 100 mm.
Parameter Value Unit
male diameter 60 mm
slat angle 10 °
slat thickness 2 mm
flange width 20 mm
central reinforcement yes

📦 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 #5689

2 object(s)
- format STL
Rectangular box with lid STL file – 99×74×20 mm, wall thickness 2 mm
Rectangular box with lid STL file – 99×74×20 mm, wall thickness 2 mm
View of object #0
STL 3D file for a rectangular box with a lid. The box measures 99 mm in length, 74 mm in width, and 20 mm in height. Wall thickness is 2 mm, giving the box a thin-wall design. The box has rounded edges inside and out. A clearance is provided for an accurate lid-to-box fit. The internal dimensions, excluding rounding, are 95 mm × 70 mm × 16 mm.
Parameter Value Unit
length 99 mm
width 74 mm
height 20 mm
wall thikness 2 mm

📦 Model #2454

1 object(s)
- format STL
Corner bracket 100×100 mm STL 3D file, thickness 8 mm, hole diameter 8 mm
Corner bracket 100×100 mm STL 3D file, thickness 8 mm, hole diameter 8 mm
Download this 3D file of a right-angle bracket with a central reinforcing bar in STL 3D format. The dimensions are 100 mm in length, 100 mm in height, 30 mm in width, and 8 mm in thickness. The screw holes are designed with a diameter of 8 mm. Chamfers are done to the holes to seat the screw heads. The central reinforcement bar improves rigidity and provides two passages for fastening. This bracket prints without support, printed flat on the build plate.
Parameter Value Unit
length 100 mm
height 100 mm
width 30 mm
thickness 8 mm
hole diameter 8 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 #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 #3664

1 object(s)
- format STL
O'ring STL file ID 33.8 × CS 3 mm
O'ring STL file ID 33.8 × CS 3 mm
3D model of O-ring (torus-shaped seal) with dimensions ID (inner diameter) 33.8 mm / CS 3  mm. External diameter (OD) is 39.8 mm.
Parameter Value Unit
inner diameter (ID) 33.8 mm
cross section (CS) 3 mm

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.