Free Mechanical & Engineering Models

Gears, Tesla valves, linkages, and print-in-place mechanisms

Some of the most fascinating 3D prints are the ones that move or demonstrate a principle: planetary gear sets, Tesla valves, compliant flexures, cam mechanisms, and print-in-place linkages. They are equal parts desk toy and engineering lesson.

This collection gathers free mechanical and engineering 3D models: working gearboxes, fluidic Tesla valves, flexure mechanisms, cams, and demonstration models. Every file is free to download from the original creator's listing.

Mechanical prints reward a tuned printer: run a tolerance test first so gears mesh and joints move freely. Print at 0.12 to 0.16 mm layers, and keep clearances generous on any part that needs to rotate.

40 trending picks

Micro Catapult 3D model
Micro Catapult
Thingiverse · LukeTansell
 Flying Sea Turtle 3D model
Flying Sea Turtle
Thingiverse · amaochan
 Parametric pulley - lots of tooth profiles 3D model
Parametric pulley - lots of tooth profiles
Thingiverse · droftarts
 Squishy Turtle 3D model
Squishy Turtle
Thingiverse · jakejake
 Platform Jack [Fully Assembled, No Supports] 3D model
Platform Jack [Fully Assembled, No Supports]
Thingiverse · Intentional3D
 Spirograph 3D model
Spirograph
Thingiverse · 3Domas
 Fully 3D-printable wind-up car gift card 3D model
Fully 3D-printable wind-up car gift card
Thingiverse · Bribro12
 Gear Bearing 3D model
Gear Bearing
Thingiverse · emmett
 3D-printable Davinci catapult gift card 3D model
3D-printable Davinci catapult gift card
Thingiverse · Bribro12
 Watch Escapement Desk Toy 3D model
Watch Escapement Desk Toy
Thingiverse · LarkysPrints
 Screwless Cube Gears 3D model
Screwless Cube Gears
Thingiverse · emmett
 Nautilus Gears 3D model
Nautilus Gears
Thingiverse · MishaT
 3D printed mechanical Clock with Anchor Escapement 3D model
3D printed mechanical Clock with Anchor Escapement
Thingiverse · TheGoofy
 best 3D-printable bearing 3D model
best 3D-printable bearing
Thingiverse · Bribro12
 Toyota 4 Cylinder Engine 22RE, Complete working model 3D model
Toyota 4 Cylinder Engine 22RE, Complete working model
Thingiverse · ericthepoolboy
 Predator Action Pliers 3D model
Predator Action Pliers
Thingiverse · ecoiras
 Fully 3D-printable turntable 3D model
Fully 3D-printable turntable
Thingiverse · Bribro12
 Icosahedron Gears Fidget Toy 3D model
Icosahedron Gears Fidget Toy
MakerWorld · bensbigolbeard
 Automatic Transmission Model 3D model
Automatic Transmission Model
Thingiverse · emmett
 Elliptical Gear with no center pivot 3D model
Elliptical Gear with no center pivot
Thingiverse · cohlwiler
 Three Heart Gears 3D model
Three Heart Gears
Thingiverse · emmett
 PRINT-IN-PLACE SPRING LOADED BOX 3D model
PRINT-IN-PLACE SPRING LOADED BOX
Thingiverse · Turbo_SunShine
 GEARBOX 3D model
GEARBOX
Thingiverse · mijael08
 Three Cube Gears 3D model
Three Cube Gears
Thingiverse · emmett
 Print in Place Geared Hinge 3D model
Print in Place Geared Hinge
Printables · E. Soderberg
 Retracc: The Retractable Karambit Knife [Now With Magnets!!] 3D model
Retracc: The Retractable Karambit Knife [Now With Magnets!!]
Thingiverse · BiscuitsOnTheFloor
 The 3D Printed Marble Machine #2 3D model
The 3D Printed Marble Machine #2
Thingiverse · Tulio
 Wall Fixing 3D model
Wall Fixing
Thingiverse · ZacSimmo
 Geared Heart -Single Print with Moving Parts - Last Minute Gift 3D model
Geared Heart -Single Print with Moving Parts - Last Minute Gift
Thingiverse · UrbanAtWork
 Preassembled Iris Box 3D model
Preassembled Iris Box
Thingiverse · emmett
 3D-printed Watch with Tourbillon 3D model
3D-printed Watch with Tourbillon
Thingiverse · TheGoofy
 Ultimate Nut Knob Generator 3D model
Ultimate Nut Knob Generator
Thingiverse · wstein
 Iris Door Box v3 3D model
Iris Door Box v3
Thingiverse · countspatula
 CR-10 Extruder Knob 3D model
CR-10 Extruder Knob
Thingiverse · ReplayMD
 Boneheads: Skull Box w/ Brain - via 3DKitbash.com 3D model
Boneheads: Skull Box w/ Brain - via 3DKitbash.com
Thingiverse · 3DKitbash
 Squishy Turtle by jakejake 3D model
Squishy Turtle by jakejake
MakerWorld · TmnRsmn
 Triaxial Tourbillon Clock Make/Mods 3D model
Triaxial Tourbillon Clock Make/Mods
Thingiverse · mcmaven
 Printable Trumpet 3D model
Printable Trumpet
Thingiverse · LtDan
 Open Source Universal Ball Joint (to reuse!) 3D model
Open Source Universal Ball Joint (to reuse!)
Thingiverse · DieZopfe
 Fingerdigger 3D model
Fingerdigger
Thingiverse · Zippitybamba

Frequently asked questions

Are these 3D models free to download?
Yes. Every model in this collection is free to download from the original creator's listing on platforms like Cults3D, MyMiniFactory, Thingiverse, Printables, and MakerWorld. Thinger links you to the source; it never re-hosts files.
How is this collection curated?
Models are matched to this topic automatically and ordered by how often Thinger users save them, so the list updates as new models trend. Check back for fresh picks.
What do I need to print these models?
Any home FDM or resin 3D printer works for most models here. Open the model page for details, then grab the file from the original listing and check the creator's suggested print settings.

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