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

Can’t find the model? Generate it! Trusted by makers worldwide.

To your specs in a few clicks!

Round box with lid STL 3D file ⌀ 100 mm - Height: 20 mm, Shell: 3 mm

Shelf bracket 110×110 mm STL file, thickness 8 mm, hole diameter 6 mm

L-bracket 200×200 mm STL file, thickness 5 mm, hole diameter 6 mm

Rectangular-base box with lid STL 3D file – 120×80×50 mm, wall thickness 3 mm

Clip-on pipe holder Ø40 mm STL 3D file · Pan head screw Ø5 mm

Small parts organizer with 1 drawer 80×80×80 mm STL file, thickness: 3 mm

Rectangular tube adapter STL file 100x40 mm to 80x80 mm – transition: 80 mm

L-bracket 250×100 mm STL file, thickness 8 mm, hole diameter 6 mm

Pot STL file, inner: base Ø40 mm, top Ø80 mm, height 50 mm - wall thickness 3 mm

Oval hose adapter STL file 60x20 mm to 60x20 mm – transition: 140 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

Oval duct transition fitting STL file 100.1x100 mm to 80x40 mm – transition: 20 mm 📦 #4342

1 object(s) - format STL

View of object #0

Latest user-generated 3D models

Round box with lid STL 3D file ⌀ 57 mm - Height: 25 mm, Shell: 2 mm 📦 #9460

2 object(s) - format STL

View of object #0

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 #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 #2690

1 object(s)

- format STL

Tube elbow STL 3D file 180° ⌀OD: 32 mm ⌀ID: 29 mm thickness: 1.5 mm

3D file of an elbow with a 180° angle in STL format. This pipe elbow features an external diameter of 32 mm and an internal diameter of 29 mm. This results in a tube thickness of 1.5 mm.

Parameter	Value	Unit
outer diameter	32	mm
inner diameter	29	mm
angle	180	°
end fillets	no

📦 Model #4060

1 object(s)

- format STL

Pipe elbow STL file 150° ⌀OD: 76 mm ⌀ID: 70 mm thickness: 3 mm

Model of a pipe elbow with a 150° angle in STL format. This elbow features an external diameter of 76 mm and an internal diameter of 70 mm. This results in a tube thickness of 3 mm. End fillets make it easier to assemble.

Parameter	Value	Unit
outer diameter	76	mm
inner diameter	70	mm
angle	150	°
end fillets	yes

📦 Model #2134

1 object(s)

- format STL

Round-to-Rectangular Tube Adapter STL file ⌀76.2 mm to 200×50.8 mm, thickness 4 mm + offset

Download this file in STL format of a round-to-rectangular adapter with an outer diameter of ⌀76.2 mm and a rectangular section with internal dimensions 200×50.8 mm. The shell thickness is 4 mm and the overall length is 166 mm. The adapter has an offset of 20 mm along the Y axis.

Parameter	Value	Unit
cylinder outer diameter	76.2	mm
cylinder inlet length	76	mm
rectangle internal length	200	mm
rectangle internal height	50.8	mm
rectangle inlet length	50	mm
offset Z	0	mm
offset Y	20	mm
total length	166	mm
thickness	4	mm
chamfer	no chamfer

📦 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 #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 #2568

2 object(s)

- format STL

Small parts organizer with 1 drawer 80×35×150 mm STL file, thickness: 2 mm

Download this model of a sorting cabinet with drawers in 3D STL format. This model includes 1 drawer, arranged in 1 rows and 1 columns. In detail, this means 1 rows of 1 drawers. Each drawer offers a storage volume of 80 mm wide, 35 mm high, and 150 mm deep. The wall thickness is 2 mm. The global dimensions of the structure measure 88.5 x 41.5 x 156 mm. All the objects in this model are intended to be printable without support generation.

Parameter	Value	Unit
number of rows	1
number of columns	1
inner drawer depth	150	mm
inner drawer width	80	mm
inner drawer height	35	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

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 #1113

2 object(s)

- format STL

Round box with lid STL file ⌀ 40 mm - Height: 35 mm, Shell: 2 mm

Download this cylindrical box in STL format. Its diameter is 40 mm and its height is 35 mm. The walls have a thickness of 2 mm.

Parameter	Value	Unit
external diameter	40	mm
total height	35	mm
wall thickness	2	mm
fit clearance	0.1	mm
inner bottom fillet	0	mm

📦 Model #3500

1 object(s)

- format STL

Clip-on tube support Ø10 mm STL file · Countersunk screw Ø3 mm

Download this 3D model of a Ø10 mm clip-on pipe mount in STL format. The fastening is done by means of a flat head screw Ø3 mm. This pipe support clip is intended for a secure hold with easy setup.

Parameter	Value	Unit
tube diameter	10	mm
hole diameter	3	mm
countersunk screw	yes

📦 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 #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

📦 Model #4280

1 object(s)

- format STL

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 #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 #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 #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 #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 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 #2133

1 object(s)

- format STL

Round-to-Rectangular Tube Adapter STL 3D file ⌀76.2 mm to 300×50.8 mm, thickness 4 mm

Download this file in STL format of a round-to-rectangular adapter with an external diameter of ⌀76.2 mm and a rectangular section with internal dimensions 300×50.8 mm. The wall thickness is 4 mm and the overall length is 166 mm. A chamfer is present on the outside of the cylindrical end to ease insertion.

Parameter	Value	Unit
cylinder outer diameter	76.2	mm
cylinder inlet length	76	mm
rectangle internal length	300	mm
rectangle internal height	50.8	mm
rectangle inlet length	50	mm
offset Z	0	mm
offset Y	0	mm
total length	166	mm
thickness	4	mm
chamfer	chamfer on t...

📦 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 #3362

1 object(s)

- format STL

Protective grid STL file, center-to-center: 65x65mm, mesh: 5mm - Ø4mm

Square protective honeycomb grid model as a STL file. Mounting holes are placed at the four corners (center-to-center 65x65 mm), each with a diameter of Ø4 mm. The overall dimensions reach 73x73 mm, with regular 5 mm cell size for balanced airflow and protection. This grid provides both mechanical protection and airflow.

Parameter	Value	Unit
length or center-to-center	65	mm
width or center-to-center	65	mm
mesh size	5	mm
dual color	no
holes	yes
hole diameter	4	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 #4325

1 object(s)

- format STL

Oval hose adapter STL 3D file 220x100 mm to 185x55 mm – transition: 24 mm

STL 3D file for an oval duct coupling. On side A, the internal cross-section is 220x100 mm, whereas on side B it is 185x55 mm. The sleeve on side A provides a useful length of 5 mm, and on side B 6 mm. The transition links the two ends over 24 mm, with a total overall length of 35 mm. A thickness of 1 mm provides a very light, thin shell. The external chamfers improve fit when inserting the adapter into ducts or hoses. Compared to side A, side B is shifted by 11 mm along the Y axis and 11 mm along the Z axis.

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	6	mm
thickness	1	mm
transition length	24	mm
Y offset	11	mm
Z offset	11	mm
end chamfers	outside

📦 Model #1459

1 object(s)

- format STL

O-ring STL file ID 12.2 × CS 2.2 mm

3D model of O-ring (torus-shaped seal) with dimensions Internal diameter 12.2 mm by section thickness 2.2 mm. The outer diameter is therefore 16.6 mm.

Parameter	Value	Unit
inner diameter (ID)	12.2	mm
cross section (CS)	2.2	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 #2322

1 object(s)

- format STL

Tube adapter STL file ⌀ 44–24 mm (Length: 90 mm)

Straight tube adapter ⌀44 mm to ⌀24 mm in STL format. Length of this junction is 90 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 have no fillet.

Parameter	Value	Unit
side A length	30	mm
side A outer diameter	44	mm
side A thickness	2	mm
side B length	40	mm
side B outer diameter	24	mm
side B thickness	2	mm
transition length	20	mm
axis offset	0	mm
ends fillet	no fillet

📦 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 #2394

1 object(s)

- format STL

Tube adapter STL 3D file ⌀ 110–80 mm (Length: 63 mm)

Straight tube reducer ⌀110 mm to ⌀80 mm in STL format. Final length of this connector is 63 mm. The thickness of the tubes is identical: 4 mm. The larger-diameter tube has a length of 25 mm, the smaller one of 25 mm as well. The ends feature an external fillet to ease the connection.

Parameter	Value	Unit
side A length	25	mm
side A outer diameter	110	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	fillet on th...

📦 Model #3120

1 object(s)

- format STL

O'ring STL 3D file ID 11 × CS 3.7 mm

STL file of sealing ring with dimensions Inner diameter 11 mm / CS (cross section) 3.7 mm. External diameter (OD) resulting is 18.4 mm.

Parameter	Value	Unit
inner diameter (ID)	11	mm
cross section (CS)	3.7	mm

📦 Model #1532

1 object(s)

- format STL

Pipe elbow STL 3D file 180° ⌀OD: 20 mm ⌀ID: 16 mm thickness: 2 mm

File of an elbow with a 180° angle in STL format. This elbow features an external diameter of 20 mm and an internal diameter of 16 mm. This results in a tube thickness of 2 mm. End fillets make it easier to assemble.

Parameter	Value	Unit
outer diameter	20	mm
inner diameter	16	mm
angle	180	°
end fillets	yes

📦 Model #1677

1 object(s)

- format STL

O-ring STL 3D file ID 28 × CS 7 mm

3D file of O-ring (torus-shaped seal) with dimensions ID 28 mm / CS 7 mm. The outer diameter is 42 mm.

Parameter	Value	Unit
inner diameter (ID)	28	mm
cross section (CS)	7	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.