Lego Technic Back to Back Double Actuator Build




Introduction: Lego Technic Back to Back Double Actuator Build

These are just some shots of the complete build. There were 2 modifications to pieces that are needed. The 2 black through pieces that are 2 bricks long needed to be turned into 1 1/2 bricks long to set the worm gear into the proper place.

Step 1: Parts Needed

These are the parts you will need to complete this build.

Step 2: The Start

Put the twisted bricks with the axle size hole on the axles and the pin size out halfway along the axles.

Slide the axles into the bricks with the 2 long axles on the outside and the short one on the inside.

Then add 4 of the 3x1/2 blocks one on each side sliding them done the axles tight to the long yellow bricks.

Step 3: Adding and Attaching the Actuators

First, add the bases to the actuators. Then slide them down the axles till they are tight with the 3x1/2 bricks.

Then insert the 1 1/2 long pins into the ends of the bricks short side out. Be sure they are at the end of the brick so when they are attached to the actuator bases they don't block the holes that the axles will go through.

Secondly, you will need to add the gears to the 3 brick long axles and insert them into the actuators.

Step 4: Setting Up the Gearing System

First, you want to put the larger gear in the middle hole of the bricks in the middle of the build.

Next, you want to be sure that the small gears are all on the same side of the actuator bases so they will all either extend or retract the actuators when turned. Then insert the 1 1/2 pins into the bricks on the last hole of the brick as done before, then insert them into the actuator base.

After, slide the long bricks onto the axles attaching the actuator bases together. Once that is done slide the 2x1/2 bricks onto the axles and tighten everything together.

Be sure to do this on both sides of the build.

Step 5: Leveling Out the The Sides

First thing insert the black pins into the two side holes right beside the middle hole in the 5x1/2 bricks then insert the black pins into the long bricks.

Then slide the L 1/2 bricks onto the 1/2 black pin that is sticking out and on the axles sticking out. On the middle axle slide the small single 1/2 "brick" onto the middle axle.

Secondly, you want to insert the black pins into the 2 hole bricks and the red axles into 3 of the 3x1/2 bricks.

Then slide the last 1/2 of the red axle into the tops of the L 1/2 bricks, after attaching the 2 hole bricks with the black pins into the 3x1/2 bricks and the long brick.

Be sure to do this on both sides of the build.

Step 6: Finishing the Large Build

First, slide the large gear onto middle axle the two small gears onto the axles on either side.

Then slide the 5x1/2 brick onto the axles and slide the small 1x1/2 "bricks" onto the end of the axles.

Be sure to do this on both sides of the build.

Secondly, slide the axle down the middle holes of the build then add the (black "slider brick"**) then worm gear and then the second (black "slider brick"**)

**These bricks need to be modified from 2 bricks long to 1 1/2 long.

Step 7: Starting the "gear Box"

First, slide the 1x1/2 "blocks" onto the axle then slide the gear tight to the blocks. Then insert the pin/axle pins into the U block and attach the T block to the pins.

After slide the axle through the T blocks and put the gear on the axle on the inside of the U block.

Secondly, put the pin/axle pins into the right angle axle ends and the 1 1/2 pins into the holes with the 1/2 out. Then insert the pin side of the pin/axle in the axle ends into the T blocks.

Finally, add the 3 pin skinny block to either side of the axle ends

Step 8: Finishing the "gear Box"

First, put the pin/axle pins into the ends of the 5x1/2 blocks and the 1/2 "blocks" onto the axle side of the pin/axle pins. Then attach the 1/2 pin side of the pin/axle pins into the U block and the other ends onto the 1/2 side of the 1 1/2 pins in the axle ends.

Secondly, put the gear in place and slide the axle through the gear and the T blocks. After put 2 1/2 "blocks" on either side of the axle tight to the T block and the gear.

Finally, attach the axle connector on the end of the axle on the gear side of the axle.

Step 9: Attaching It All Together

It doesn't matter which side you attach the "gearbox" to.

First, you want to attach the axle side of the pin/axle pins to the axle shaped holes in the ends of the actuators then slide the axle running down the middle of the main build into the axle connector of the gearbox.

Finally, add an axle through the "pin" holes in the actuators and a gear in the U block that meshes with the gear at the base of the U block.

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    5 Discussions

    Poppy Ann
    Poppy Ann

    1 year ago

    Great instructable I built a bulldozer out of technical lego using the rams to lift and tilt a bucket on the front and lower a ripper tooth on the rear then added a radio control system to it getting the radio system to work with lego was quite hard lego should sell radio control servos that just click into a model using the motors I just fitted a brushed motor electronic speed control to each track motor II use to drive it around the front room using it to pick up things that I dropped, my only problem with it was I took it apart before I took any photos I used lego to build brackets to hold the soundbar to my tv which is still doing its job after over 3 years I built a lift/lower system for one of the cheap webcams and added a small adjustable lens to it so it acts as a microscope it may not look the best but it works much better than the plastic ones they sell on the internet and cost less as well.
    keep up the good work. Regards Poppy Ann.


    2 years ago

    Great work! This really makes me miss my Lego lol.


    2 years ago

    looks coll but what odes it do?


    Reply 2 years ago

    Its something that can be added to peoples builds that are looking for more strength and travel. It doubles the load a single actuator can take as well as the length of travel. It also has a lot of gear reduction so as to not overload or cause gears to skip.


    2 years ago

    That's neat, thanks for sharing :)