Lego 4 Speed Rotary Gearbox with build instructions
This strong and versatile four speed sequential lego gearbox uses the new "Change over rotary catch" (from the bugatti chiron, 42083) component to smoothly select from 1 of four speeds using a single lever. The gearbox implements 1st, 2nd, 3rd and reverse speeds. The rotary catch is kept at neat 90 degree angles using a mini stepper.
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Lego Technic 100 Part 4 Speed Gearbox
This video shows how to make a Lego Technic 4 Speed gearbox using 100 parts. The gearbox is a manual gearbox makes gearing ratios of 1/3, 5/9, 1/1 and 5/3.
The gearbox is demonstrated by hand and by using a Lego Technic Large Power functions motor.
...read moreLego Technic Dual Function Gearbox
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 Technic 2 Speed Automatic Gearbox with Booster Motor
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 MOC 256 Speed Gearbox
Here I present a 256 speed gearbox controlled by 8 switches. This design is based on a 2 differential N to P gear ratio design presented in one of my other videos. The gearbox allows 256 different gearing ratios to be selected including 1:44, 1:34, 1:33, 1:32, 1:28, 1:27, 1:24, 1:2...read more
Lego Technic New 12/20 Gear High Speed Friction Test
The Lego Technic set 42140 App-Controlled Transformation Vehicle introduces two new gears - a flat version of the 12 tooth bevel gear and a flat version of the 20 tooth bevel gear. These gears are designed to have less friction.
In this follow up video I measure the high speed difference ...read more
New Flat 12/20 Gear Friction
The Lego Technic set 42140 App-Controlled Transformation Vehicle introduces two new gears - a flat version of the 12 tooth bevel gear and a flat version of the 20 tooth bevel gear. These gears are designed to have less friction.
In this video I measure the difference in gearing efficiency...read more
Gearing Ratio Calculator Tool Help
Measuring Gearbox Efficiency
This video describes a method for measuring the efficiency of a gearbox using the Lego Technic Powered Up hub. Gearbox efficiency is defined as the ratio of the output power to the input power and here I show how to measure each of these values to allow you to calculate the overall efficiency.read more
Lego Technic Gearing Ratio Calculator Tool
Here I present my new Lego Technic Gearing Ratio Calculator tool. This tool allows you to upload your Lego Technic .ldr (Lego Draw) file and it will simulate the gearing system and visualize it as well as showing the gearing ratios relative to the input component.
The tool can be accessed...read more
Lego Technic Multi Function Gearbox with Build Instructions
This lego technic multi function gearbox implements two separate functions using just a single motor. It implements the two functions by exploiting the direction of rotation of the motor and implementing one function for the forward direction and a function selector in the reverse direction. The ...read more