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!

Small parts organizer with 6 drawers 40×15×30 mm STL 3D file, thickness: 2 mm

Rectangular pipe adapter STL 3D file 110x110 mm to 80x80 mm – transition: 20 mm

Tube adapter STL file ⌀ 100–51 mm (Length: 160 mm)

Pipe elbow STL file 120° ⌀OD: 40 mm ⌀ID: 34 mm thickness: 3 mm

Round air vent STL 3D file ∅ 70 mm, slat angle: 45° with central reinforcement

Pipe clip holder Ø50 mm STL file · Countersunk screw Ø5 mm

Rectangular pipe adapter STL 3D file 60x60 mm to 60x60 mm – transition: 60 mm

Round-to-Rectangular Tube Adapter STL file ⌀125 mm to 200×60 mm, thickness 3 mm + offset

Multi-compartment box STL file: 3 compartments of 45×45×45 mm

Round box with lid STL 3D file ⌀ 80 mm - Height: 50 mm, Shell: 3 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 prism STL 3D file 100×77×22 mm 📦 #752

1 object(s) - format STL

Latest user-generated 3D models

Tube adapter STL file ⌀ 40–12 mm (Length: 50 mm) 📦 #12753

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 #4425

1 object(s)

- format STL

Protective grid STL file, center-to-center: 90x64mm, mesh: 3mm - Ø4mm

Download this rectangular grid model in STL format. Mounting holes are placed at the four corners (center-to-center 90x64 mm), each with a diameter of Ø4 mm. The overall dimensions reach 98x72 mm, with extra fine 3 mm cell size for maximum protection. This type of grid serves both protection and ventilation roles.

Parameter	Value	Unit
length or center-to-center	90	mm
width or center-to-center	64	mm
mesh size	3	mm
dual color	no
holes	yes
hole diameter	4	mm

📦 Model #2644

3 object(s)

- format STL

Small parts organizer with 1 drawer 80×35×150 mm STL 3D file, thickness: 2 mm

File of a multi-drawer unit in 3D STL format. This model features 1 box, arranged in 1 rows and 1 columns. In detail, this means 1 rows of 1 boxes. Each box has usable dimensions of 80 mm wide, 35 mm high, and 150 mm deep. The wall thickness is 2 mm. The box features 1 divider, allowing up to 2 compartments. The global dimensions of the box measure 88.5 x 41.5 x 156 mm. All the objects in this model are intended to be printable without support.

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	one divider ...

📦 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 #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 #1558

1 object(s)

- format STL

Round air vent STL 3D file ∅ 90 mm, slat angle: 35° with central reinforcement

Design of a round grille for air circulation in STL format. Its insertion diameter is 90 mm. The slats have an angle of 35° and a high thickness of 2.4 mm. A centered vertical reinforcement strengthens the whole structure. This aeration grille features a prominent flange of 18 mm. The total diameter of the model is 126 mm.

Parameter	Value	Unit
male diameter	90	mm
slat angle	35	°
slat thickness	2.4	mm
flange width	18	mm
central reinforcement	yes

📦 Model #1124

1 object(s)

- format STL

Tube adapter STL file ⌀ 50–40 mm (Length: 50 mm)

Tube junction ⌀50 mm to ⌀40 mm in STL 3D format. Length of this coupler is 50 mm. The thickness of the tubes is identical: 2 mm. The larger-diameter tube has a length of 20 mm, the smaller one of 20 mm as well. The ends have a fillet to facilitate the connection of the two tubes.

Parameter	Value	Unit
side A length	20	mm
side A outer diameter	50	mm
side A thickness	2	mm
side B length	20	mm
side B outer diameter	40	mm
side B thickness	2	mm
transition length	10	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

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 #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 #3570

1 object(s)

- format STL

Tube clip holder Ø31 mm STL 3D file · Countersunk screw Ø3 mm

3D model of a Ø31 mm snap-on tube holder in STL format. The fastening is done by means of a flat head screw Ø3 mm. This snap-on tube holder is designed for a secure hold with easy setup.

Parameter	Value	Unit
tube diameter	31	mm
hole diameter	3	mm
countersunk screw	yes

📦 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 #2177

1 object(s)

- format STL

O'ring STL 3D file ID 48 × CS 1.7 mm

Model of O-ring (torus-shaped seal) with Inner diameter 48 mm by section thickness 1.7 mm. Outer diameter (OD) resulting is 51.4 mm.

Parameter	Value	Unit
inner diameter (ID)	48	mm
cross section (CS)	1.7	mm

📦 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 #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 #4345

1 object(s)

- format STL

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 #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 #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 #1179

5 object(s)

- format STL

Color-coded compartment box STL 3D file: 24 compartments of 20×20×20 mm

This 3D model in STL format of a organizer box with colored rings includes 24 cavities measuring 20×20×20 mm each. Overall dimensions of the box are 141×95×23 mm. Fillets of 2 mm applied to each compartment, aid item retrieval from the slots.

Parameter	Value	Unit
number of rows	4
number of columns	6
compartment length	20	mm
compartment width	20	mm
compartment height	20	mm
wall thickness	3	mm
compartment fillet (radius)	2	mm
row colors	ABCD

📦 Model #2309

1 object(s)

- format STL

Washer / Flat Gasket STL file ⌀ID: 50 mm ⌀OD: 55 mm thickness: 5 mm + fillets

Download this 3D model of flat gasket / washer in STL file format. This model features an inner diameter of ⌀50 mm and an outer diameter of ⌀55 mm. The thickness is 5 mm. Fillets are applied on the outer diameter, each with a value of 1.5 mm. These finishes are present on both faces.

Parameter	Value	Unit
inner diameter	50	mm
outer diameter	55	mm
thickness	5	mm
finish	fillet
finish position	outer
sides	two sides
finish value	1.5	mm

📦 Model #933

1 object(s)

- format STL

U-shaped handle STL 3D file 50×100×14 mm (Center-to-center 86 mm)

Download this STL 3D model of a simple U-shaped furniture handle. The external dimensions are 50×100×14 mm. This handle has a square profile and a rounded transition. A light fillet along the edges ensures a more pleasant grip. The mounting holes are 6 mm diameter and have a 86 mm center-to-center distance.

Parameter	Value	Unit
width	50	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	6	mm

📦 Model #2838

1 object(s)

- format STL

Tube adapter STL 3D file ⌀ 99–62 mm (Length: 90 mm)

Tubing adapter ⌀99 mm to ⌀62 mm in STL 3D format. Total length of this fitting is 90 mm. The thickness of the tubes is identical: 3 mm. The larger-diameter tube has a sleeve length of 35 mm, the smaller one of 35 mm as well. The ends are rounded on the inside.

Parameter	Value	Unit
side A length	35	mm
side A outer diameter	99	mm
side A thickness	3	mm
side B length	35	mm
side B outer diameter	62	mm
side B thickness	3	mm
transition length	20	mm
axis offset	0	mm
ends fillet	fillet on th...

📦 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 #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 #3976

1 object(s)

- format STL

Multi-compartment box STL file: 40 compartments of 10×10×5 mm

This 3D model in STL format provides 40 cavities measuring 10×10×5mm each. Overall dimensions are 62×98×7mm. Fillets of 2mm applied to each compartment provide a better grip stored in the compartments.

Parameter	Value	Unit
number of rows	8
number of columns	5
compartment length	10	mm
compartment width	10	mm
compartment height	5	mm
wall thickness	2	mm
compartment fillet (radius)	2	mm

📦 Model #1824

1 object(s)

- format STL

Pipe elbow STL 3D file 90° ⌀OD: 27 mm ⌀ID: 25 mm thickness: 1 mm

Model of an elbow with a 90° angle in STL format. This elbow has an outer diameter of 27 mm and an inner diameter of 25 mm. The tube thickness is therefore 1 mm.

Parameter	Value	Unit
outer diameter	27	mm
inner diameter	25	mm
angle	90	°
end fillets	no

📦 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 #2266

1 object(s)

- format STL

Pipe elbow STL file 90° ⌀OD: 40 mm ⌀ID: 38 mm thickness: 1 mm

Model of a pipe elbow with a 90° angle in STL format. This pipe elbow features an outer diameter of 40 mm and an inner diameter of 38 mm. This results in a tube thickness of 1 mm. The ends feature fillets to make it easier to assemble.

Parameter	Value	Unit
outer diameter	40	mm
inner diameter	38	mm
angle	90	°
end fillets	yes

📦 Model #2646

1 object(s)

- format STL

Corner bracket 250×150 mm STL 3D file, thickness 5 mm, hole diameter 5 mm

Download this model of an angle bracket with reinforcement in STL 3D format. The dimensions are 250 mm in length, 150 mm in height, 20 mm in width, and 5 mm in thickness. The screw holes have 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. No support is needed to print this bracket, placed flat directly on the build plate.

Parameter	Value	Unit
length	250	mm
height	150	mm
width	20	mm
thickness	5	mm
hole diameter	5	mm
chamfer on the holes	yes

📦 Model #1026

1 object(s)

- format STL

Rectangular prism STL 3D file 25×25×40 mm and 5 mm fillets

A STL 3D model of a box. The final dimensions are 25 by 25 by 40 mm. A large fillet softens the edges.

Parameter	Value	Unit
length	25	mm
width	25	mm
height	40	mm
fillet radius	5	mm

📦 Model #4218

2 object(s)

- format STL

Round box with lid STL 3D file ⌀ 100 mm - Height: 200 mm, Shell: 3 mm

Get this cylindrical storage box in STL format. Its diameter is 100 mm and its total height is 200 mm. The walls have a thickness of 3 mm. A fillet located at the bottom of the box makes it easier to grab stored objects inside.

Parameter	Value	Unit
external diameter	100	mm
total height	200	mm
wall thickness	3	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

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.