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Rectangular prism STL 3D file 100×77×22 mm 📦 #752

1 object(s) - format STL

gizmo

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Tubing adapter STL 3D file ⌀ 53–46 mm (Length: 45 mm) 📦 #12860

1 object(s) - format STL

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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 #4227

1 object(s)
- format STL
Tubing adapter STL 3D file ⌀ 73–51 mm (Length: 150 mm)
Tubing adapter STL 3D file ⌀ 73–51 mm (Length: 150 mm)
Tube reducer ⌀73 mm to ⌀51 mm in STL format. Length of this coupler is 150 mm. The thickness of the tubes is identical: 2 mm. The larger-diameter tube has a sleeve length of 50 mm, the smaller one of 50 mm as well. The ends are raw.
Parameter Value Unit
side A length 50 mm
side A outer diameter 73 mm
side A thickness 2 mm
side B length 50 mm
side B outer diameter 51 mm
side B thickness 2 mm
transition length 50 mm
axis offset 0 mm
ends fillet no fillet

📦 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 #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 #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 #1084

1 object(s)
- format STL
Multi-compartment box STL 3D file: 200 compartments of 2×2×2 mm
Multi-compartment box STL 3D file: 200 compartments of 2×2×2 mm
This parametric compartment box provides 200 compartments measuring 2×2×2mm each. Overall dimensions are 42×82×4mm.
Parameter Value Unit
number of rows 20
number of columns 10
compartment length 2 mm
compartment width 2 mm
compartment height 2 mm
wall thickness 2 mm
compartment fillet (radius) 0.8 mm

📦 Model #3122

1 object(s)
- format STL
Honeycomb grille STL 3D file, center-to-center: 180x180mm, mesh: 10mm - Ø3mm
Honeycomb grille STL 3D file, center-to-center: 180x180mm, mesh: 10mm - Ø3mm
3D square protective honeycomb grid model in STL format. Mounting holes are placed at the four corners (center-to-center 180x180 mm), each with a diameter of Ø3 mm. The overall dimensions reach 186x186 mm, with very open 10 mm cell size for peak ventilation. This grid functions as both a mechanical guard and a ventilation panel.
Parameter Value Unit
length or center-to-center 180 mm
width or center-to-center 180 mm
mesh size 10 mm
dual color no
holes yes
hole diameter 3 mm

📦 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 #4512

1 object(s)
- format STL
Tube elbow STL file 45° ⌀OD: 40 mm ⌀ID: 25 mm thickness: 7.5 mm
Tube elbow STL file 45° ⌀OD: 40 mm ⌀ID: 25 mm thickness: 7.5 mm
3D model of an elbow with a 45° angle in STL format. This pipe elbow has an external diameter of 40 mm and an internal diameter of 25 mm. The tube thickness is therefore 7.5 mm.
Parameter Value Unit
outer diameter 40 mm
inner diameter 25 mm
angle 45 °
end fillets no

📦 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 #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 #823

1 object(s)
- format STL
U-shaped handle STL 3D file 35×100×14 mm (Center-to-center 86 mm)
U-shaped handle STL 3D file 35×100×14 mm (Center-to-center 86 mm)
Download this STL model of a basic U-shaped handle. The overall dimensions are 35×100×14 mm. The handle has a square section and a softened transition. A fillet along the edges ensures a more comfortable grip. The openings are 4 mm diameter and have a 86 mm center-to-center distance.
Parameter Value Unit
width 35 mm
length 100 mm
thickness 14 mm
shape (0:square,1:circle) 0
transition (0:right,1:rounded) 1
fillet radius 1 mm
hole diameter 4 mm

📦 Model #2169

1 object(s)
- format STL
Round air vent STL file ∅ 60 mm, slat angle: 30° with central reinforcement
Round air vent STL file ∅ 60 mm, slat angle: 30° with central reinforcement
3D design of a round grille for ventilation in STL format. Its insertion diameter measures 60 mm. The slats have a slight angle of 30° and a high thickness of 2 mm. A vertical reinforcement strengthens the whole structure. This 3D vent cover features a flange of 10 mm. The overall diameter of this model is 80 mm.
Parameter Value Unit
male diameter 60 mm
slat angle 30 °
slat thickness 2 mm
flange width 10 mm
central reinforcement yes

📦 Model #1082

1 object(s)
- format STL
Multi-compartment box STL 3D file: 4 compartments of 35×35×35 mm
Multi-compartment box STL 3D file: 4 compartments of 35×35×35 mm
This parametric storage box provides 4 cavities measuring 35×35×35mm each. External size of the box are 79×79×38mm. Fillets of 3mm applied to each compartment provide a better grip stored in the box. The walls are particularly thick.
Parameter Value Unit
number of rows 2
number of columns 2
compartment length 35 mm
compartment width 35 mm
compartment height 35 mm
wall thickness 3 mm
compartment fillet (radius) 3 mm

📦 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 #3390

1 object(s)
- format STL
Protective grid STL file, center-to-center: 104x104mm, mesh: 10mm - Ø4mm
Protective grid STL file, center-to-center: 104x104mm, mesh: 10mm - Ø4mm
Honeycomb protective square grid file in STL format. Mounting holes are placed at the four corners (center-to-center 104x104 mm), each with a diameter of Ø4 mm. The overall dimensions reach 112x112 mm, with very open 10 mm cell size for peak ventilation. This type of grid serves both protection and ventilation roles.
Parameter Value Unit
length or center-to-center 104 mm
width or center-to-center 104 mm
mesh size 10 mm
dual color no
holes yes
hole diameter 4 mm

📦 Model #2383

1 object(s)
- format STL
Tube adapter STL 3D file ⌀ 105–80 mm (Length: 63 mm)
Tube adapter STL 3D file ⌀ 105–80 mm (Length: 63 mm)
Tube adapter ⌀105 mm to ⌀80 mm in STL 3D format. Length of this connector is 63 mm. The thickness of the tubes is identical: 4 mm. The larger-diameter tube has a sleeve length of 25 mm, the smaller one of 25 mm as well. The ends are not rounded.
Parameter Value Unit
side A length 25 mm
side A outer diameter 105 mm
side A thickness 4 mm
side B length 25 mm
side B outer diameter 80 mm
side B thickness 4 mm
transition length 13 mm
axis offset 0 mm
ends fillet no fillet

📦 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 #1909

1 object(s)
- format STL
Pipe elbow STL file 60° ⌀OD: 50 mm ⌀ID: 40.5 mm thickness: 4.75 mm
Pipe elbow STL file 60° ⌀OD: 50 mm ⌀ID: 40.5 mm thickness: 4.75 mm
3D model of an elbow with a 60° angle in STL format. This elbow has an external diameter of 50 mm and an internal diameter of 40.5 mm. This results in a tube thickness of 4.75 mm.
Parameter Value Unit
outer diameter 50 mm
inner diameter 40.5 mm
angle 60 °
end fillets no

📦 Model #4195

1 object(s)
- format STL
Pipe elbow STL 3D file 90° ⌀OD: 87 mm ⌀ID: 84 mm thickness: 1.5 mm
Pipe elbow STL 3D file 90° ⌀OD: 87 mm ⌀ID: 84 mm thickness: 1.5 mm
3D file of a pipe elbow with a 90° angle in STL format. This pipe elbow has an outer diameter of 87 mm and an inner diameter of 84 mm. This results in a tube thickness of 1.5 mm.
Parameter Value Unit
outer diameter 87 mm
inner diameter 84 mm
angle 90 °
end fillets 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 #5925

2 object(s)
- format STL
Rectangular-base box with lid STL 3D file – 100×50×50 mm, wall thickness 3 mm
Rectangular-base box with lid STL 3D file – 100×50×50 mm, wall thickness 3 mm
View of object #0
Rectangular-base box with a lid available as a STL 3D file. Box size: 100 mm × 50 mm × 50 mm (L × W × H). Wall thickness is 3 mm. Interior and exterior edges are rounded. A small clearance is included to ensure a precise fit between the box and the lid. The inner dimensions excluding rounding are 94 mm × 44 mm × 44 mm.
Parameter Value Unit
length 100 mm
width 50 mm
height 50 mm
wall thikness 3 mm

📦 Model #4345

1 object(s)
- format STL
Oval hose adapter STL 3D file 140x50 mm to 130x35 mm – transition: 40 mm
Oval hose adapter STL 3D file 140x50 mm to 130x35 mm – transition: 40 mm
Oval connector available as a STL 3D file. On side A, the internal cross-section is 140x50 mm, whereas on side B it is 130x35 mm. You get a sleeve of 8 mm on side A and 6 mm on side B. The central transition occupies 40 mm, bringing the overall length to 54 mm. The internal chamfers help start the duct insertion more easily.
Parameter Value Unit
side A internal width 140 mm
side A internal height 50 mm
sleeve length on side A 8 mm
side B internal width 130 mm
side B internal height 35 mm
sleeve length on side B 6 mm
thickness 2 mm
transition length 40 mm
Y offset 0 mm
Z offset 0 mm
end chamfers inside

📦 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 #4088

2 object(s)
- format STL
Protective grid STL 3D file, 100x70mm, mesh: 3mm
Protective grid STL 3D file, 100x70mm, mesh: 3mm
View of object #0
Honeycomb rectangular grid model in STL format. The overall size is 100x70 mm, with fine 3 mm cell size for strong protection. A secondary color border highlights the perimeter. This type of grid serves both protection and ventilation roles.
Parameter Value Unit
length or center-to-center 100 mm
width or center-to-center 70 mm
mesh size 3 mm
dual color yes
holes no

📦 Model #3349

1 object(s)
- format STL
Round-to-Rectangular Tube Adapter STL 3D file ⌀50 mm to 152×45 mm, thickness 3 mm
Round-to-Rectangular Tube Adapter STL 3D file ⌀50 mm to 152×45 mm, thickness 3 mm
Download this 3D file in STL format of a round-to-rectangular adapter with an external diameter of ⌀50 mm and a rectangular section with internal dimensions 152×45 mm. The wall thickness is 3 mm and the overall length is 110.3 mm. A chamfer is present on the outside of the cylindrical end.
Parameter Value Unit
cylinder outer diameter 50 mm
cylinder inlet length 25 mm
rectangle internal length 152 mm
rectangle internal height 45 mm
rectangle inlet length 25 mm
offset Z 0 mm
offset Y 0 mm
total length 110.3 mm
thickness 3 mm
chamfer chamfer on t...

📦 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 #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 #3186

3 object(s)
- format STL
Small parts organizer with 36 drawers 30×20×50 mm STL 3D file, thickness: 2 mm
Small parts organizer with 36 drawers 30×20×50 mm STL 3D file, thickness: 2 mm
View of object #0
3D file of a multi-drawer box in 3D STL format. This model features 36 drawers, arranged in 6 rows and 6 columns. Practically speaking, this means 6 rows of 6 drawers. Each drawer provides an inside space of 30 mm wide, 20 mm high, and 50 mm deep. The wall thickness is 2 mm. The drawers feature 2 dividers each, which allows up to 3 compartments per drawer and up to 108 sections in total. The global dimensions of the structure measure 221 x 149 x 56 mm. All the objects in this model were designed to be printable without support generation.
Parameter Value Unit
number of rows 6
number of columns 6
inner drawer depth 50 mm
inner drawer width 30 mm
inner drawer height 20 mm
wall thickness 2 mm
removable divider two divider ...

📦 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 #3957

1 object(s)
- format STL
Tubing adapter STL file ⌀ 80–22 mm (Length: 49 mm)
Tubing adapter STL file ⌀ 80–22 mm (Length: 49 mm)
Inline tube reducer ⌀80 mm to ⌀22 mm in STL 3D format. Length of this sleeve is 49 mm. The thickness of the tubes is identical: 2 mm. The larger-diameter tube has a sleeve length of 10 mm, the smaller one of 9 mm. The ends have no fillet.
Parameter Value Unit
side A length 10 mm
side A outer diameter 80 mm
side A thickness 2 mm
side B length 9 mm
side B outer diameter 22 mm
side B thickness 2 mm
transition length 30 mm
axis offset 0 mm
ends fillet no fillet

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.