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Rectangular prism STL 3D file 100×70×29 mm 📦 #755

1 object(s) - format STL

gizmo

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Tube STL 3D file OD 23.5 mm, ID 22 mm, length 50 mm 📦 #11447

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 #1284

2 object(s)
- format STL
Color-coded compartment box STL 3D file: 4 compartments of 20×20×15 mm
Color-coded compartment box STL 3D file: 4 compartments of 20×20×15 mm
View of object #0
This STL file for a sectioned box with color markers provides 4 cavities measuring 20×20×15 mm each. The total dimensions are 49×49×18 mm. Fillets of 2 mm applied to all compartments, aid item retrieval from the box.
Parameter Value Unit
number of rows 2
number of columns 2
compartment length 20 mm
compartment width 20 mm
compartment height 15 mm
wall thickness 3 mm
compartment fillet (radius) 2 mm
row colors AA

📦 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 #1420

1 object(s)
- format STL
Pipe elbow STL file 25° ⌀OD: 40 mm ⌀ID: 34 mm thickness: 3 mm
Pipe elbow STL file 25° ⌀OD: 40 mm ⌀ID: 34 mm thickness: 3 mm
3D model of an elbow with a 25° angle in STL format. This elbow has an external diameter of 40 mm and an internal diameter of 34 mm. The tube thickness is therefore 3 mm.
Parameter Value Unit
outer diameter 40 mm
inner diameter 34 mm
angle 25 °
end fillets no

📦 Model #989

1 object(s)
- format STL
U-shaped handle STL 3D file 50×140×14 mm (Center-to-center 126 mm)
U-shaped handle STL 3D file 50×140×14 mm (Center-to-center 126 mm)
Download this model of a simple U-shaped handle. The external dimensions are 50×140×14 mm. This handle features a circular cross-section and a 90-degree transition. The openings are 5 mm diameter and have a 126 mm center-to-center distance.
Parameter Value Unit
width 50 mm
length 140 mm
thickness 14 mm
shape (0:square,1:circle) 1
transition (0:right,1:rounded) 0
fillet radius 0 mm
hole diameter 5 mm

📦 Model #1820

1 object(s)
- format STL
Washer / Flat Gasket STL 3D file ⌀ID: 57 mm ⌀OD: 75 mm thickness: 5 mm + chamfers
Washer / Flat Gasket STL 3D file ⌀ID: 57 mm ⌀OD: 75 mm thickness: 5 mm + chamfers
Model of washer / flat gasket in STL file format. This model has an internal diameter of ⌀57 mm and an external diameter of ⌀75 mm. The total thickness is 5 mm. Chamfers are applied on both the internal diameter and the external diameter, each with a value of 4 mm.
Parameter Value Unit
inner diameter 57 mm
outer diameter 75 mm
thickness 5 mm
finish chamfer
finish position inner + oute...
sides one side
finish value 4 mm

📦 Model #2247

1 object(s)
- format STL
Round-to-Rectangular Tube Adapter STL file ⌀119 mm to 114×79 mm, thickness 3 mm + offset
Round-to-Rectangular Tube Adapter STL file ⌀119 mm to 114×79 mm, thickness 3 mm + offset
Download this model in STL format of a round-to-rectangular adapter with an external diameter of ⌀119 mm and a rectangular section with inner dimensions 114×79 mm. The shell thickness is 3 mm and the overall length is 100 mm. The adapter has an offset of 2 mm along the Y axis and 17.5 mm along the Z axis.
Parameter Value Unit
cylinder outer diameter 119 mm
cylinder inlet length 30 mm
rectangle internal length 114 mm
rectangle internal height 79 mm
rectangle inlet length 30 mm
offset Z 17.5 mm
offset Y 2 mm
total length 100 mm
thickness 3 mm
chamfer no chamfer

📦 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 #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 #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 #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 #877

1 object(s)
- format STL
U-shaped handle STL 3D file 35×140×14 mm (Center-to-center 126 mm)
U-shaped handle STL 3D file 35×140×14 mm (Center-to-center 126 mm)
Download this STL model of a simple U-shaped furniture handle. The overall dimensions are 35×140×14 mm. The handle has a square cross-section combined with a smooth transition. A fillet along the edges allows for a more comfortable grip. The mounting holes are 4 mm diameter and have a 126 mm center-to-center distance.
Parameter Value Unit
width 35 mm
length 140 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 #4429

1 object(s)
- format STL
Round-to-Rectangular Tube Adapter STL 3D file ⌀103 mm to 290×28 mm, thickness 3 mm
Round-to-Rectangular Tube Adapter STL 3D file ⌀103 mm to 290×28 mm, thickness 3 mm
Download this model in STL format of a round-to-rectangular tube adapter with an external diameter of ⌀103 mm and a rectangular section with internal dimensions 290×28 mm. The wall thickness is 3 mm and the total length is 148 mm.
Parameter Value Unit
cylinder outer diameter 103 mm
cylinder inlet length 50 mm
rectangle internal length 290 mm
rectangle internal height 28 mm
rectangle inlet length 50 mm
offset Z 0 mm
offset Y 0 mm
total length 148 mm
thickness 3 mm
chamfer no chamfer

📦 Model #2535

1 object(s)
- format STL
Support bracket 250×250 mm STL file, thickness 12 mm, hole diameter 5 mm
Support bracket 250×250 mm STL file, thickness 12 mm, hole diameter 5 mm
Download this file of a right-angle bracket reinforced in STL format. The dimensions are 250 mm in length, 250 mm in height, 26 mm in width, and 12 mm in thickness. The drill holes are designed with a diameter of 5 mm. Chamfers are applied to the holes to seat the screw heads. The reinforcing bar enhances mechanical strength and provides two passages for screwdriver access. Support generation is not required for printing this bracket, placed flat directly on the build plate.
Parameter Value Unit
length 250 mm
height 250 mm
width 26 mm
thickness 12 mm
hole diameter 5 mm
chamfer on the holes yes

📦 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 #1808

1 object(s)
- format STL
Pipe elbow STL 3D file 1° ⌀OD: 20 mm ⌀ID: 18 mm thickness: 1 mm
Pipe elbow STL 3D file 1° ⌀OD: 20 mm ⌀ID: 18 mm thickness: 1 mm
3D model of a pipe elbow with a 1° angle in STL format. This elbow features an outer diameter of 20 mm and an inner diameter of 18 mm. This results in a tube thickness of 1 mm. End fillets make it easier to insert.
Parameter Value Unit
outer diameter 20 mm
inner diameter 18 mm
angle 1 °
end fillets yes

📦 Model #4444

2 object(s)
- format STL
Round box with lid STL file ⌀ 72 mm - Height: 190 mm, Shell: 3 mm
Round box with lid STL file ⌀ 72 mm - Height: 190 mm, Shell: 3 mm
View of object #0
Download this circular box model in STL format. Its diameter is 72 mm and its height is 190 mm. The walls have a thickness of 3 mm.
Parameter Value Unit
external diameter 72 mm
total height 190 mm
wall thickness 3 mm
fit clearance 0.1 mm
inner bottom fillet 0 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 #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 #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 #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 #2514

1 object(s)
- format STL
Multi-compartment box STL file: 40 compartments of 46.5×49.6×68 mm
Multi-compartment box STL file: 40 compartments of 46.5×49.6×68 mm
This 3D model in STL format features 40 sections measuring 46.5×49.6×68mm each. The total dimensions of the box are 390×260×70mm.
Parameter Value Unit
number of rows 5
number of columns 8
compartment length 46.5 mm
compartment width 49.6 mm
compartment height 68 mm
wall thickness 2 mm
compartment fillet (radius) 1 mm

📦 Model #3172

1 object(s)
- format STL
Angle bracket 180×180 mm STL 3D file, thickness 12 mm, hole diameter 5 mm
Angle bracket 180×180 mm STL 3D file, thickness 12 mm, hole diameter 5 mm
File of a corner bracket reinforced in STL 3D format. The dimensions are 180 mm in length, 180 mm in height, 14 mm in width, and 12 mm in thickness. The drill holes have a diameter of 5 mm. Chamfers are applied to the holes for a cleaner fit of the screws. The central reinforcement bar improves rigidity and includes two openings for fastening. This bracket prints without support, printed flat directly on the build plate.
Parameter Value Unit
length 180 mm
height 180 mm
width 14 mm
thickness 12 mm
hole diameter 5 mm
chamfer on the holes yes

📦 Model #2992

1 object(s)
- format STL
Mounting bracket 195×195 mm STL 3D file, thickness 12 mm, hole diameter 8 mm
Mounting bracket 195×195 mm STL 3D file, thickness 12 mm, hole diameter 8 mm
Download this 3D model of a support bracket with a central reinforcement in STL 3D format. The dimensions are 195 mm in length, 195 mm in height, 30 mm in width, and 12 mm in thickness. The screw holes are designed with a diameter of 8 mm. Chamfers are done to the holes to improve the seating of the heads. The central reinforcement bar reduces bending and provides two passages for fastening. This bracket prints without support, printed flat directly on the build plate.
Parameter Value Unit
length 195 mm
height 195 mm
width 30 mm
thickness 12 mm
hole diameter 8 mm
chamfer on the holes yes

📦 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 #774

1 object(s)
- format STL
Rectangular prism STL 3D file 100×29×70 mm
Rectangular prism STL 3D file 100×29×70 mm
Download this 3D model of a box as an STL file. The overall dimensions are 100 by 29 by 70 mm. A fillet smooths the edges.
Parameter Value Unit
length 100 mm
width 29 mm
height 70 mm
fillet radius 2 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 #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 #4453

1 object(s)
- format STL
Oval hose adapter STL 3D file 150x40 mm to 130x35 mm – transition: 40 mm
Oval hose adapter STL 3D file 150x40 mm to 130x35 mm – transition: 40 mm
Oval duct transition adapter in STL 3D file format. Side A offers an internal cross-section of 150x40 mm and side B 130x35 mm. The sleeve on side A provides a useful length of 8 mm, and on side B 6 mm. Between the two sleeves, the transition runs over 40 mm, resulting in an overall length of 54 mm. Internal chamfers at the ends improve assembly and make insertion smoother.
Parameter Value Unit
side A internal width 150 mm
side A internal height 40 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 #1538

1 object(s)
- format STL
Round-to-Rectangular Tube Adapter STL file ⌀150 mm to 100×50 mm, thickness 3 mm + offset
Round-to-Rectangular Tube Adapter STL file ⌀150 mm to 100×50 mm, thickness 3 mm + offset
Download this file in STL format of a round-to-rectangular tube adapter with an external diameter of ⌀150 mm and a rectangular section with inner dimensions 100×50 mm. The wall thickness is 3 mm and the total length is 200 mm. The adapter has an offset of 50 mm along the Z axis. A chamfer is present on the outside of the cylindrical end.
Parameter Value Unit
cylinder outer diameter 150 mm
cylinder inlet length 25 mm
rectangle internal length 100 mm
rectangle internal height 50 mm
rectangle inlet length 50 mm
offset Z 50 mm
offset Y 0 mm
total length 200 mm
thickness 3 mm
chamfer chamfer on t...

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.