TOOLS

Gearing Ratio Calculator

Check out the Beta version my Lego Technic Gearing Ratio Calculator Tool:

This tool allows you to upload your Lego Technic project .ldr file and analyse the gearing ratios between any two connected gears or axles. Currently supports most gears, axles, worm gears, some differentials, cv joints and universal joints. See the video tutorial on how to use it. It is a work in progress and I would love to hear your feedback on it. Click here to try it out.

Note: As of 25 Septemeber 2021 the tool supports CV joints, linear speed via the radius of the component and improves on the frame rate for higher numbers of parts in a model).

Technic Elbow Art

This is a tool to create "Lego Technic Elbow Art" - a series of intertwined elbow pieces as a single sequence. Choose your dimensions and search parameters and search for new dense solutions and set a record! 

Download your Elbow Art as an .ldr file and build it yourself. Click here to try it out!

Lego Technic 2 Speed Automatic Gearbox with Booster Motor

23 Dec 2020

A lego technic 2 speed automatic gearbox is presented. The point of difference of this automatic 2 speed gearbox is a secondary booster motor is activated once the torque detector senses a large enough torque on the output of the automatic gearbox.

The second motor is turned on by a pole reversing switch component driven by the torque detector differential which simultaneously drives an orange rotary catch component. The rotary catch not only engages a secondary gearing path that reduces the overall gearing ratio but also engages the booster motor to provide more power at the output as required by the higher load conditions.

The gearbox is demonstrated in action by using a configurable loading mechanism that uses 10 lego clutch gears to provide ten levels of torque loading to simulate different loading situations.

More to explore

Lego Technic 2 Speed Auto Gearbox - a new hope - with build instructions

28 Nov 2020
Lego Technic 2 Speed Auto Gearbox - a new hope - with build instructions

This Lego technic 2 speed automatic gearbox design uses a worm gear for torque detection and gear switching combined. Previous Lego 2 speed automatic gearboxes have used a Lego differential for torque detection to drive an orange rotary catch to switch gears using a switch component.

The ...read more

Lego Technic Gearbox Theory Applied - how to apply theory to help design 2 speed automatic gearboxes

10 Nov 2020
Lego Technic Gearbox Theory Applied - how to apply theory to help design 2 speed automatic gearboxes

This video applies lego technic gearbox, torque, and gearing ratio theory to design a prototype lego 2 speed automatic gearbox. First I describe the main components of an automatic gearbox, namely a gearing ratio selector and a torque detector. The ideal gear switch over torque point is described...read more

Lego Technic torque in practice - how to work with torque in automatic gearbox design

29 Oct 2020
Lego Technic torque in practice - how to work with torque in automatic gearbox design

n this video I present a ten level Lego Technic torque creation gadget for testing lego power function motors and automatic gear switching mechanisms. The effect of torque on a large lego PF motor is tested against the theoretical power curve to compare the optimal gear switching point in practic...read more

Lego 2 speed automatic car. Part 1

3 Oct 2020
Lego 2 speed automatic car. Part 1

This video explores the use of the lego technic "smoothly switching 2 speed automatic gearbox" inside of a test car to see how well it works to climb up a ramp.

The gearing ratio of the 2nd gear of the 2 speed automatic gearbox can be set using a manual 4 speed gearbox to choose...read more

Lego 2 Speed Automatic gearbox - worm gear prototype. Includes build instructions.

26 Sep 2020
Lego 2 Speed Automatic gearbox -  worm gear prototype. Includes build instructions.

This video present a lego technic 2 speed automatic gearbox based on using a worm gear for torque detection.  The 2 speed transmission gearbox works by using the linear counteraction force on the worm gear to connect a gear to create a second speed.

This 2nd speed is added to the mai...read more

Lego Technic smoothly switching 2 speed automatic gearbox evolution with instructions

11 Sep 2020
Lego Technic smoothly switching 2 speed automatic gearbox evolution with instructions

This video presents my latest compact and smoothly switching 2 speed automatic gearbox made out of Lego Technic.  It is both smoothly switching and compact.

The MOC gearbox automatically switches down in gearing ratio when the load on the output is sufficiently high by using a new te...read more

Lego Technic Powerful 2 Speed Auto Gearbox

3 Jun 2022
Lego Technic Powerful 2 Speed Auto Gearbox

Here I present my design for a compact and powerful Lego Technic 2 speed automatic gearbox.

The gearbox uses the Lego Technic Powered Up functions to detect speed and deduce torque from that to make gear switching decisions. The gearbox switches between a high gear of 1 to 4, to a low gea...read more

Lego Technic Applied Gearbox Theory Improved

20 Nov 2020
Lego Technic Applied Gearbox Theory Improved

This Lego Technic video demonstrates an improved design of a Lego technic 2 speed automatic gearbox based on a theoretical approach. Typically a Lego automatic gearbox consists of two stages namely a gear selector and a torque detector. In this video, both of these components are improved upon.read more

Lego Technic 3 Speed Automatic Gearbox - FAIL!

18 Sep 2020
Lego Technic 3 Speed Automatic Gearbox - FAIL!

This video presents a lego technic 3 speed automatic gearbox design that failed to work as expected. This design is based on an earlier design of a 2 speed automatic gearbox with smooth transmission that worked very well.  That technic gearbox was extended by adding another speed to the oran...read more

Lego Technic 2 Speed Automatic Gearbox - Compact! With build Instructions.

15 Aug 2020
Lego Technic 2 Speed Automatic Gearbox - Compact! With build Instructions.

Here I present a design for a compact lego technic 2 speed automatic  gearbox. Instead of using a differential to react to torque on the output it uses the force on the gear teeth to push a liftarm to automatically change the gearing ratio to the 2nd speed once the torque threshold has been ...read more