Free custom STL files and 3D models for 3D printers

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Pipe elbow STL 3D file 90° ⌀OD: 40 mm ⌀ID: 34 mm thickness: 3 mm

Oval duct transition adapter STL file 80.1x80 mm to 80x40 mm – transition: 20 mm

Rectangular duct adapter STL 3D file 100x20 mm to 80x20 mm – transition: 20 mm

Multi-compartment box STL 3D file: 14 compartments of 14×14×5 mm

Enclosure with screw-mounted lid STL file: 80×80×40 mm (with ventilation on the lid)

Tube adapter STL file ⌀ 60–30 mm (Length: 140 mm)

Square-base box with lid STL 3D model – 70×70×40 mm, wall thickness 4 mm

Shelf bracket 100×100 mm STL file, thickness 12 mm, hole diameter 6 mm

Tube adapter STL file ⌀ 100–60 mm (Length: 70 mm)

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

Browse a growing library of free STL files and 3D models — or generate custom parts online to your exact specs.

Featured Model of the Day

Rectangular-base box with lid STL 3D model – 170×95×110 mm, wall thickness 3 mm 📦 #6422

2 object(s) - format STL

Latest user-generated 3D models

Tube clip Ø65 mm STL file · Flat head screw Ø6 mm 📦 #10403

1 object(s) - format STL

From the Blog

Why Modeling Strategy Matters in Procedural CAD Modeling

2025-12-14 · 3D Modeling · sylvain

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 #2837

1 object(s)

- format STL

Honeycomb grid STL file, 280x127mm, mesh: 10mm

Rectangular grid model as a STL file. The overall size is 280x127 mm, with very large 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	280	mm
width or center-to-center	127	mm
mesh size	10	mm
dual color	no
holes	no

📦 Model #4497

1 object(s)

- format STL

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 #2861

3 object(s)

- format STL

Small parts organizer with 5 drawers 20×15×40 mm STL 3D file, thickness: 2 mm

Download this 3D model of a storage case in STL format. This model features 5 compartments, arranged in 1 rows and 5 columns. Practically speaking, this means 1 rows of 5 compartments. Each compartment offers a storage volume of 20 mm wide, 15 mm high, and 40 mm deep. The wall thickness is 2 mm. The compartments come with 1 divider each, which allows up to 2 compartments per compartment and up to 10 sections in total. The global dimensions of the box measure 134.5 x 21.5 x 46 mm. All the objects in this model were designed to be printable without support generation.

Parameter	Value	Unit
number of rows	1
number of columns	5
inner drawer depth	40	mm
inner drawer width	20	mm
inner drawer height	15	mm
wall thickness	2	mm
removable divider	one divider ...

📦 Model #3502

1 object(s)

- format STL

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 #6362

2 object(s)

- format STL

Rectangular-base box with lid STL 3D model – 84×45×20 mm, wall thickness 2 mm

Rectangular-base box with a lid provided as a STL 3D file. Overall dimensions are 84 mm long, 45 mm wide, and 20 mm tall. The box features thin 2 mm walls. Interior and exterior edges are rounded. A small clearance is included to ensure a precise fit between the box and the lid. The internal dimensions, excluding rounding, are 80 mm × 41 mm × 16 mm.

Parameter	Value	Unit
length	84	mm
width	45	mm
height	20	mm
wall thikness	2	mm

📦 Model #1032

1 object(s)

- format STL

O'ring STL 3D file ID 0.74 × CS 1.02 mm

3D model in STL format of O-ring with ID (inner diameter) 0.74 mm × section thickness 1.02 mm. External diameter (OD) corresponds to 2.78 mm.

Parameter	Value	Unit
inner diameter (ID)	0.74	mm
cross section (CS)	1.02	mm

📦 Model #3057

1 object(s)

- format STL

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 #4476

1 object(s)

- format STL

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 #3612

1 object(s)

- format STL

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 #2390

1 object(s)

- format STL

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 #4326

1 object(s)

- format STL

Hose-shaped reducer STL 3D file 220x100 mm to 185x55 mm – transition: 20 mm

Oval duct adapter in STL 3D file format. The internal cross-section on side A is 220x100 mm, while on side B it is 185x55 mm. A uniform useful length of 5 mm is available on both sleeves. The transition links the two ends over 20 mm, with a total overall length of 30 mm. With 1 mm of thickness, the wall remains flexible and material-efficient. The external edges at the ends are chamfered, which simplifies inserting the adapter into the duct. Side B is offset by 9 mm along the Y axis and 9 mm along the Z axis relative to side A.

Parameter	Value	Unit
side A internal width	220	mm
side A internal height	100	mm
sleeve length on side A	5	mm
side B internal width	185	mm
side B internal height	55	mm
sleeve length on side B	5	mm
thickness	1	mm
transition length	20	mm
Y offset	9	mm
Z offset	9	mm
end chamfers	outside

📦 Model #2913

1 object(s)

- format STL

Mounting bracket 150×150 mm STL 3D file, thickness 6 mm, hole diameter 7 mm

Download this model of a mounting bracket reinforced in STL 3D format. The dimensions are 150 mm in length, 150 mm in height, 25 mm in width, and 6 mm in thickness. The screw holes are designed with a diameter of 7 mm. Chamfers are applied to the holes to seat the screw heads. The central reinforcement bar reduces bending and provides two openings for fastening. No support is needed to print this bracket, placed flat on the print bed.

Parameter	Value	Unit
length	150	mm
height	150	mm
width	25	mm
thickness	6	mm
hole diameter	7	mm
chamfer on the holes	yes

📦 Model #2039

2 object(s)

- format STL

Small parts organizer with 6 drawers 100×100×150 mm STL file, thickness: 2 mm

File of storage drawers in STL format. This model contains 6 drawers, arranged in 3 rows and 2 columns. Specifically, this means 3 rows of 2 drawers. Each drawer provides an inside space of 100 mm wide, 100 mm high, and 150 mm deep. The wall thickness is 2 mm. The total size of the box measure 215 x 315.5 x 156 mm. All the objects in this model are intended to be printed without support.

Parameter	Value	Unit
number of rows	3
number of columns	2
inner drawer depth	150	mm
inner drawer width	100	mm
inner drawer height	100	mm
wall thickness	2	mm
removable divider	none

📦 Model #3038

2 object(s)

- format STL

Honeycomb grid STL file, center-to-center: 210x140mm, mesh: 3mm - Ø4mm

Download this honeycomb protective rectangular grid as a STL file. Mounting holes are placed at the four corners (center-to-center 210x140 mm), each with a diameter of Ø4 mm. The overall dimensions reach 218x148 mm, with very fine 3 mm cell size for maximum protection. A secondary color frame emphasizes the border. 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	140	mm
mesh size	3	mm
dual color	yes
holes	yes
hole diameter	4	mm

📦 Model #3849

1 object(s)

- format STL

Tube adapter STL file ⌀ 250–50 mm (Length: 80 mm)

Straight tube connector ⌀250 mm to ⌀50 mm in STL 3D format. Final length of this coupler is 80 mm. The larger-diameter tube has a thickness of 5 mm and a length of 30 mm. The smaller-diameter tube has a thickness of 3 mm and a length of 30 mm as well. The ends are raw.

Parameter	Value	Unit
side A length	30	mm
side A outer diameter	250	mm
side A thickness	5	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 #1483

1 object(s)

- format STL

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 #4503

1 object(s)

- format STL

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 #1918

1 object(s)

- format STL

Tube adapter STL file ⌀ 50–45 mm (Length: 90 mm)

Straight tube coupler ⌀50 mm to ⌀45 mm in STL 3D format. Length of this adapter is 90 mm. The thickness of the tubes is identical: 5 mm. The larger-diameter tube has a length of 30 mm, the smaller one of 30 mm as well. The ends are raw.

Parameter	Value	Unit
side A length	30	mm
side A outer diameter	50	mm
side A thickness	5	mm
side B length	30	mm
side B outer diameter	45	mm
side B thickness	5	mm
transition length	30	mm
axis offset	0	mm
ends fillet	no fillet

📦 Model #3247

1 object(s)

- format STL

O'ring STL file ID 80 × CS 5.3 mm

Model of O-ring with dimensions Inner diameter (ID) 80 mm × section thickness 5.3 mm. External diameter (OD) is 90.6 mm.

Parameter	Value	Unit
inner diameter (ID)	80	mm
cross section (CS)	5.3	mm

📦 Model #2078

3 object(s)

- format STL

Small parts organizer with 6 drawers 40×40×150 mm STL file, thickness: 2 mm

3D file of a sorting cabinet with drawers in 3D STL format. This model includes 6 boxes, arranged in 2 rows and 3 columns. In detail, this means 2 rows of 3 boxes. Each box provides an inside space of 40 mm wide, 40 mm high, and 150 mm deep. The wall thickness is 2 mm. The boxes come with 1 divider each, which allows up to 2 sections per box and up to 12 sections in total. The global dimensions of the box come to 141.5 x 91 x 156 mm. All the objects in this model are intended to be printed without support generation.

Parameter	Value	Unit
number of rows	2
number of columns	3
inner drawer depth	150	mm
inner drawer width	40	mm
inner drawer height	40	mm
wall thickness	2	mm
removable divider	one divider ...

📦 Model #4475

1 object(s)

- format STL

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 #3890

1 object(s)

- format STL

Right-angle bracket 150×100 mm STL file, thickness 12 mm, hole diameter 5 mm

3D file of a corner bracket reinforced in STL format. The dimensions are 150 mm in length, 100 mm in height, 20 mm in width, and 12 mm in thickness. The holes have a diameter of 5 mm. Chamfers are done to the holes to seat the screw heads. The reinforcing bar enhances mechanical strength and provides two openings for screwdriver access. This bracket prints without support, placed flat directly on the build plate.

Parameter	Value	Unit
length	150	mm
height	100	mm
width	20	mm
thickness	12	mm
hole diameter	5	mm
chamfer on the holes	yes

📦 Model #989

1 object(s)

- format STL

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 #4201

1 object(s)

- format STL

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 #1681

1 object(s)

- format STL

O-ring STL 3D file ID 70 × CS 4 mm

STL file of sealing ring with dimensions Internal diameter 70 mm / CS 4 mm. External diameter (OD) is therefore 78 mm.

Parameter	Value	Unit
inner diameter (ID)	70	mm
cross section (CS)	4	mm

📦 Model #4417

2 object(s)

- format STL

Enclosure with screw-mounted lid STL 3D file: 120×100×35 mm (with ventilation on the lid and under the enclosure)

Download this enclosure with lid in 3D STL format. The dimensions are 120 mm long by 100 mm wide and 35 mm high. The lid is 10 mm high. Wall thickness is 2 mm. This enclosure has significant cooling area on the lid and under the base.

Parameter	Value	Unit
length	120	mm
width	100	mm
total height	35	mm
lid height	10	mm
wall thickness	2	mm
screw margin	0	mm
fit clearance	0.1	mm
cooling level	8
cooling zone(s)	cutouts on b...

📦 Model #4414

2 object(s)

- format STL

Round box with lid STL 3D file ⌀ 134 mm - Height: 20 mm, Shell: 2 mm

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 #2987

1 object(s)

- format STL

Honeycomb grille STL file, 220x220mm, mesh: 10mm

Square grid model as a STL file. The overall size is 220x220 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	220	mm
width or center-to-center	220	mm
mesh size	10	mm
dual color	no
holes	no

📦 Model #4396

1 object(s)

- format STL

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 #3491

1 object(s)

- format STL

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

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.