# 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!

# Lego Technic RC 3 Speed Manual Gearbox

11 Jan 2021

A Lego Technic 3 speed remote controlled gearbox is presented with the design process explained. The lego RC 3 speed gearbox allows you to change gears up and down using a power functions remote control. The 3 speed gearbox implements the gear changing mechanism using two parallel axles each with gears arranged in such a way that shifting one of the axles to one of three possible positions meshes the gears with 3 different gearing ratios. The gearing ratios implemented are 3:5, 1:1 and 5:3.

The gear shifting axle is controlled by a lever mechanism driven by the 4 state stepper from the lego technic bugatti chiron set. This mechanism in turn is driven by a medium power functions motor activated by the remote control.

The main driving axle is driven by a lego technic large PF motor.

# More to explore

## Lego Technic RC 3 SPEED CAR - change gears, drive and steer using remote control

19 Jan 2021

An improved version of a lego technic RC 3 speed gearbox is implemented into a remote control lego car. This video shows three main improvements over the previous gearbox design. The first is an improvement is to replace the 90 degree bugatti stepper  with a PF servo motor reducing the gearb...read more

## Lego 2 speed automatic car. Part 1

3 Oct 2020

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

## Spirograph Machine

19 Dec 2023

Here I present a Lego Technic Spirograph machine programmed using Powered Up. The powered up controller is used to maintain the desired gearing ratio between the turn table and the inner gear to draw a spirograph that replicates the real original spirograph drawing toy.

## Lego Technic Powered Up 3 Speed Automatic Car

14 Aug 2021

This video presents a new lego technic 3 speed automatic RC car. The gearbox uses the lego technic powered up hub and 3 motors to drive, steer and switch gears. The car's 3 speed automatic gearbox has 3 forward speeds with gear ratios 1:1, 3:5 and 1:5 and has been programmed us...read more

## Lego Technic Single Motor Tank

1 Apr 2021

Here I present a lego technic tank driven by a single lego power functions motor. The lego RC tank can be controlled remotely using a single remote channel and driven forwards, backwards, and steered left and right. These functions are implemented by using a single large PF motor and exploiting t...read more

## Lego Technic Dual Function Gearbox

3 Mar 2021

This gearbox solves the problem of needing three lego technic motors to remotely control a car with 3 functions namely driving, steering and gear changing capability. The lego gearbox implements two functions at once by exploiting the direction of rotation of the driving motor and ...read more

## Lego Ferrari 488 GTE Manual 8 Speed Gearbox

29 Jan 2021

This video shows the design and construction of an 8 speed manual gearbox inspired by the Lego Technic Ferrari 488 GTE model that has come out in 2021. The lego technic set is called set #42125 Ferrari 488 GTE "AF Corse #51".

The gearbox gearing ratios closely approximate the ge...read more

## 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 ...read more

## Lego Technic 2 Speed Auto Car Ramp Challenge - Part 2

10 Dec 2020

A lego technic 2 speed automatic gearbox is put to the test by incorporating it into a lego 2 speed automatic car.  This lego 2 speed automatic gearbox implements a number of design principles aimed at improving the gearbox performance - namely of placing the torque detector on a separate pa...read more

## Lego Technic 3 Speed Automatic Gearbox - FAIL!

18 Sep 2020

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